Installation of Tankless Water Heater

donnamatrix · 05-05-2009, 12:42 PM

We are contemplating the installation of a Rinnai tankless water heater to replace the electric storage water heater that was originally installed in our home. We have received estimates from several area companies for the purchase and install of the unit. Bay Street Discount in Ossipee has tendered an attactive estimate for the unit and has recommended a plumber to install the unit. Has anyone had any dealings with Bay Street Discount on this sort of installation? We would be very interested in hearing any comments on this company and on your experiences with these tankless water heaters.

fatlazyless · 05-05-2009, 02:27 PM

Rinnai builds quality that lasts and lasts and lasts. Don't have a Rinnai water heater but do have a couple Rinnai hot air heaters.

Amerigas-Laconia is a Rinnai dealer and does installations. If you have them do the install then you get the item-install-propane all from the same company and could be they offer you a deal on a propane pre-buy deal, too. Plus, right now is a slow time of year for Amerigas-Laconia.

For purchasing the Rinnai item without installation, www.alsheating.com in Brunswick Maine has low prices.

jmen24 · 05-05-2009, 04:06 PM

One side of the coin, A tankless water heater saves energy by only heating water that you are using at that time without any storage of unused energy. If you do not demand hot water on a regular basis or for a continued amount of time, you can save some money on energy bills by not wasting energy to keep water warm until you use it. They take up no floor space and are very neat and tidy mounted on a wall.

The other side of the coin, A tankless water heater has to see a call for water before it will start to produce hot water. If you take prolonged showers the unit will run the entire time to keep up with demand, if more than one shower is used at a time (or a performance shower) volume may overwelm its ability to satisfy both locations. The startup pause (waiting for water to arrive) is slightly longer than a storage tank heater, but probably not noticable to most. May not be DIY friendly depending on owners ability to troubleshoot.

Writers conclusion, These units fall under the same catagory as the flourescent light bulbs that are touted as green. The application needs to fit the use. Flourescent bulbs only consume less energy if they are in locations that a light will remain on for a long enough period of time to offset the greater amount of energy it takes to start one up. Tankless water heaters work on the opposite thinking, you will save more money if you do not have to use it all the time.

When customers of ours are looking into the possibility of adding one of these units we will sit down and present the above information and then ask then what there daily hot water usage is, this is not an exact number thing, just how many showers a day, dishwasher usage per week, washing machine usage per week and then we add up all these items to get an idea of how long this unit will run on an average day. Compare the Btu's of the tankless against the storage heater to get an idea of consumption for each unit, and that is your answer of if it works for you. Your local plumbing supply company have people on staff that can do these calculations for you if you provide the water usage in GPM of each faucet and water consuming appliance as well as duration used along with frequency. They typically sell both so there is no pressure to sell you on one vs the other.

We have installed many of these units in our customers homes that are second and third homes that do not get rented at all and see use only a few days out of the year. We do not put many in primary residences due to the amount of water used on a daily basis.

I hope that helps and was understandable.

One more thing, you may want to compare an electric water heater (being that is what you have now) against a gas unit first to get the better of the two before moving on to compare with the tankless.

dpg · 05-06-2009, 06:36 AM

jmen24 - then again if you do not call for hot water to much and have a storage tank isn't it a very minimal cost for it to just there "maintaining" the temp for the water it's holding?

SIKSUKR · 05-06-2009, 07:03 AM

Not sure what jmen is talking about.I have never had any issues in reguard to demand with my tankless.Unlimited hot water.

jmen24 · 05-06-2009, 07:44 AM

I am talking about energy consumption to make the same amount of water. Your tankless has an output rating of GPM, you take your GPM output and convert to btu's used to heat your output GPM to get the overall efficiency of your application.
If you read my post completely, I stated that it all depends on usage and energy consumption, not everyone is going to demand the same amount of water.
For an example, in a recently completed project, a 6'x5' performance shower was added in an existing system. Either way an upgrade was needed as the 12 shower heads and body sprays used 11GPM. That required the use of 380gal of storage to satisfy demand. A tankless unit would not even come close to providing the amount of GPM's needed to satisfy demand even if it was solely for that shower, not to mention it would tax the well pump for supply, because that runs the whole time as well.

Hopefully that illustrates my point a little better.

jmen24 · 05-06-2009, 07:53 AM

dpg
You are correct in that is costs more to make hot water than it does to maintain hot water, but a fair amount of our clients only come up a few weekends out of the year and that includes winter and they typically shut down the water system to prevent massive flooding in the winter if the system has a freeze up. In those situations we recommend the tankless, as the hot water is right there when then come up and want to have a shower right off.

Mee-n-Mac · 05-06-2009, 03:23 PM

Quote:

Originally Posted by jmen24

dpg
You are correct in that is costs more to make hot water than it does to maintain hot water, but a fair amount of our clients only come up a few weekends out of the year and that includes winter and they typically shut down the water system to prevent massive flooding in the winter if the system has a freeze up. In those situations we recommend the tankless, as the hot water is right there when then come up and want to have a shower right off.

Huh ? I think it costs less to make the hot water than it does to make and maintain it, which is what your typical system does. Am I missing something here ? If you're constantly using the hot water then the difference may be small and not enough to make the extra cost of a tankless system pay for itself. We'd have gone tankless except that the plumber guy said the gas line (from the LP tank) would have to be redone as the on demand systems required more flow to make the BTUs they do. This made some sense and then again .... How many more BTUs, say over a gas range, does a typical 3 GPM tankless system produce (note: not used in winter) ? What kind of "special" pressure regulator and gas line diameter (if any) does an on demand system need vs a typical tank system ?

jmen24 · 05-06-2009, 04:10 PM

Quote:

Originally Posted by Mee-n-Mac

Huh ? I think it costs less to make the hot water than it does to make and maintain it, which is what your typical system does. Am I missing something here ? If you're constantly using the hot water then the difference may be small and not enough to make the extra cost of a tankless system pay for itself. We'd have gone tankless except that the plumber guy said the gas line (from the LP tank) would have to be redone as the on demand systems required more flow to make the BTUs they do. This made some sense and then again .... How many more BTUs, say over a gas range, does a typical 3 GPM tankless system produce (note: not used in winter) ? What kind of "special" pressure regulator and gas line diameter (if any) does an on demand system need vs a typical tank system ?

You have to remember you are making the hot water in both cases to begin with, its the different of maintaining or constantly making. A modern day stone lined water heater will hold the heat in the water for an incredible amount of time, the $200.00 units at big box stores, not so much. Just about every manufacturer of Tankless water heaters states in there product brochures about the need to pay attention to usage (almost all recommend a dedicated system for dishwashers or large soaking tubs), Rinnai has a section in there site that will actually calculate the size or number of units needed based on zip code. In our area the ambient temp of the incoming water has to be heated to a certain degree for comfort, tankless units (within the spec sections) will give you the output temp at certain GPM's (what your faucet is rated for at max output), add this to the incoming water temp and that is what you can expect at the tap. You then need to size the unit appropriately based on need.
On Rinnai's site when you plug in your information, as an example I plugged in a local zip, 3 baths, 5 shower heads (hand helds with fixed in two units) and two of the units being tub/shower combos. The result was to contact a local dealer as more than one tankless unit would be required. That gets expesive quick and there is nothing stating how many faucets being used at once, but your usage needs to be based on total possible output.

The total cost of energy used goes beyond the gas being burned to heat the water and store, but electricity used to run the well pump, circulators, etc. This is exactly what the LEED construction points are based on, not how "green" one item is but how everything works as a total package and most the "green" products that are marketed as such are not so when added into the big picture.

As for regulator and line sizing that is a question for a qualified installer or manufacturer, its a basic physic calculation but they use software to prevent the headaches. I am just a Project Manager that has a particular interest in researching and educating myself on new and old construction practices. Contact The Granite Group and talk to someone in retail sales (not the counter) they would be able to tell you the line sizing and regulator needed for a particular system.

The btu question is a little easier and a little complicated, all manufacturers post btu ratings for gas appliances, the 3GPM btu rating for a tankless will vary depending on model. 3GPM on one model will be different on another, because a larger unit can heat water hotter at 3GPM than another. You have to remember that the water at no point in time is stopping to be heated, so it has to absorb as much heat as it can as it passes through the heat chamber, the faster it moves the more energy is required to get heat into the water.

These long posts are killing me, sorry for the technical long winded explainations, hopefully I am actually answering your questions.

BlackeyCoveR · 05-06-2009, 04:51 PM

I did the same comparison and ended up staying with the electric water heater. I looked at overall energy consumption, and volume of water we need (family of 5 plus frequent guests).

Although we're at the lake most of the summer, off season not so much. So with electric, I hit the breaker every time we leave and draw no electricity. I was not able to shut off if I went with gas.

hazmatmedic · 05-07-2009, 07:18 AM

I can help with the line sizing and regulator. Most regulators provided by your lp supplier will handle the increase in the btu load of the Rinnai, but if it didn't, they would provide a higher volume regulator for your needs.

The line size is a different story and thats why having your propane supplier provide the Rinnai and installation of that product is probably the most cost effective, because they can do the whole job. Still get a quote from your supplier. The line size calculation isn't as complicated as Jmen24 leads you to believe. The NFPA code books provide that info or most technicians have a handy pocket sized book with the info. The Rinnai recommends the minimum of 3/4" IPS (iron pipe size) for propane supply, but that may have to be increased if it is a long distance from the point the gas supply enters your home.

The other questions regarding line size was standard gas H2O heaters and gas ranges. "Typical" gas ranges are @ 60,000 btus and "typical" H2O heaters are @ 40,000 btus. The standard Rinnais are @ 200.000 btus and this is why it requires a larger line.

The on-demand water heaters are not really for larger homes (more than 2 bathrooms), but are really ideal for smaller second homes. That is based upon some of the information that was provided by Jmen24.

jmen24 · 05-07-2009, 07:53 AM

Thanks for the line sizing info. I do not feel qualified to list line sizing and regualator sizes as I am not an installer, I leave those requirements to the specialized pros.

I want to make sure that I am clear in not selling one unit over the other, the tankless systems are very good, just make sure it fits your lifestyle and needs.

John E · 05-07-2009, 08:29 AM

I can't see any reason not to use the Rinnai aside from initial cost. I'm wiring a large condo project and they are using the Rinnai as their choice of water heater. 2 Bed/ 2 bath units.

wifi · 05-07-2009, 08:37 AM

200K BTUs... Yikes. Wonder if you could put a heat exchanger on it to recover some of the heat for the house/basement or what ever?

ishoot308 · 05-07-2009, 08:50 AM

I'm having a Rinnai installed in my camp in a week or two and will report back as to it's effectiveness. I have a couple of friends who have snowmobile camps in Pittsburgh New Hampshire that use Rinnais and absolutely love them. I have rarely, if ever, heard anyone who has a Rinnai say anything but positive comments. Hopefully I will be the same!

Dan

jmen24 · 05-07-2009, 10:01 AM

Rinnai is one of the easiest companies to work with regarding any issues, if you have them. They are a good choose if you are thinking of installing any type of system that they produce, tankless, monitor, etc.

upnorth · 05-07-2009, 12:04 PM

We also installed a propane-fired tankless heater and I love it. Water is very hot and we've never run out -- even with multiple simultaneous showers.

The builder recommended we go tankless and the cost differential over a propane fired hot water heater was only $170. Interestingly, when we tried to estimate what level we ought to be for propane pricing (per the deal with Our Town and Eastern propane) -- this being our first year with a new house -- the customer service rep commented that the Rinnai Tankless is very efficient and hardly enters their calculus. On the downside, every single time the hot water is turned on at the faucet for even a moment, the tankless fires up and you can hear it in certain areas of the home -- I'm sure I'm the only one that notices...

I do notice a delay, but it's really not that long, maybe 30 sec?

Island-Ho · 05-07-2009, 12:24 PM

I would hope that the unit is designed so that a very high percentage of that 200K BTU goes into heating the water and that there is very little wasted to recover for space heating, although you might get a little out of the vent flue.
I am considering using a tankless heater downstream from a solar hot water system. Does anyone know if the Rinnia fires up based on incoming water temperature or simply turns on when the water starts flowing? Obviously the second scenario would be undesirable if the incoming water is already hot enough! Currently my solar heated water flows into a backup gas fired water heater, but I would like to eliminate having to keep that tank warm all the time when there is plenty of solar heated water available.

wifi · 05-07-2009, 12:57 PM

BTU = heat required to raise one lb of water 1 degree F
Water weights about 8 lbs/gallon.

Lets guestimate we start at 50 degrees and want to get to 120 degrees. This is a 120-50=70 degree rise times 8 lbs/gallon = 560 BTUs to raise one gallon of water from 50 to 120.

So, 3 gals/min = 1680 BTUs/minute times 60 minutes = 100,800 BTUs per hour. Efficiency is ~50%?

Hmm... where am I wrong ?

jmen24 · 05-07-2009, 02:54 PM

Quote:

Originally Posted by wifi

BTU = heat required to raise one lb of water 1 degree F
Water weights about 8 lbs/gallon.

Lets guestimate we start at 50 degrees and want to get to 120 degrees. This is a 120-50=70 degree rise times 8 lbs/gallon = 560 BTUs to raise one gallon of water from 50 to 120.

So, 3 gals/min = 1680 BTUs/minute times 60 minutes = 100,800 BTUs per hour. Efficiency is ~50%?

Hmm... where am I wrong ?

Its 8.34BTUs for 1 gallon of water, but that is only skewing a little.

The 200K number I believe is arbitrary. Linked is one of the smaller units Rinnai makes and we use this for discussion http://www.rinnai.us/documentation/d.../V53e_SP-1.pdf It has a rating of .82 so, 82% efficient with a max output of 120K BTU with max flow of 5.3GPM. If you look at the graph, for 3GPM requires 98400K BTU (actual output being transfered into the water) to achieve approx. 60 degree rise in temp with 21600K BTU being lost. Obviously, this unit would not be sized properly, but it works for the point.

The 200K BTU model would not be using the full max output to achieve that rise in temp it would only be using 121K BTUs with a loss of 21K BTUs.

These units use a ambiant temperature sensor to determine output BTUs needed based on call demand.

wifi · 05-07-2009, 05:17 PM

Jmen24

Thanks for the clarification

donnamatrix · 05-21-2009, 04:23 PM

After multiple quotes and discussions with various suppliers and contactors, we have decided to move forward and have our tankless water heater installed next week. I was amazed by the range of quotes (40%) we received for the same Rinnai unit and same installation.

I did find out that, in addition to the 30% tax credit from Uncle Sam, we should qualify for a $300 rebate from the Propane Gas Association of New England. Together, these credits/rebates should pay for about 50% of the total bill.

Thanks for all the good feedback and advice. I will keep you posted as to our experience.

Misha888 · 05-25-2009, 09:58 PM

Quote:

Originally Posted by donnamatrix

After multiple quotes and discussions with various suppliers and contactors, we have decided to move forward and have our tankless water heater installed next week. I was amazed by the range of quotes (40%) we received for the same Rinnai unit and same installation.

I did find out that, in addition to the 30% tax credit from Uncle Sam, we should qualify for a $300 rebate from the Propane Gas Association of New England. Together, these credits/rebates should pay for about 50% of the total bill.

Thanks for all the good feedback and advice. I will keep you posted as to our experience.

How is the new installation working out for you?

donnamatrix · 05-28-2009, 11:13 AM

Our new Rinnai tankless heater was installed yesterday. So far, so good. No big issues during the installation. Since the heater draws very little juice, we have added it to the generator transfer panel. So now, we will have hot water when we have a power outage and are running on our generator.

The delay in getting hot water is noticable, but not much more than what we had before.

All in all, a good experience.

jmen24 · 05-28-2009, 12:53 PM

Glad to hear your install went well, having the unit on the Generator is a great idea and will come in handy when you need it.

ishoot308 · 07-07-2009, 08:01 AM

As promised I am reporting back regarding the recent installation of my on demand water heater. First off let me state that it is not a Rinnai, it is another brand made by "State Water Heaters". It looks and works exactly the same as a Rinnai brand however.

It's been installed in my camp now for about two weeks and this past weekend we really had an opportunity to put it to the test. We had six guests plus my wife and I all using hot water for showers, laundry, etc. Many times there were two showers going at once! This thing never hicupped once and worked flawlessly. I am super impressed at its performance and at how quiet it is! I have read some previous posts regarding the wait for hot water, but I am not experiencing this. The wait for hot water as the cold water in the plumbing lines between the heater and faucet is removed is there, but that is standard with any water heater and is not a factor whatsoever.

Previously we had a small electric water heater and it could have never kept up this past weekend.

I can't really comment on the cost to run as it's simply too soon but at the end of the season I will report back. So far we absolutely love the on demand water heater!

Dan

Dr. Green · 07-07-2009, 11:50 AM

Note: This is not a disinterested post. I own a store in Laconia "Sustain Ability" selling solar hot water systems, and tankless hot water - both propane and electric.

The cheapest way to heat water in the long term (even in the Lakes Region) is solar hot water (given you have sufficient solar access. Over time, it will be cheaper than even tankless water heaters (THW). If needing hot water only on a seasonal basis (i.e. - NOT winter), a flatplate system is cheapest, and certainly adequate.

If wanting hot water throughout winter, an evacuated tube solar hot water system is better, due to the superior winter performance of the evacuated tubes.

The next cheapest way is propane (or natural gas if you have it) tankless hot water whole-house systems. They should save 25% or more over an electric water tank, since they heat water only when you need it.

Next cheapest is an electric point of use tankless hot water system. If you have simple needs, many propane systems will be too big (they will work fine, but will be like having a pick-up truck instead of a SMART car). While electric THW systems use much more power than an electric tank system while heating the water, they only heat it during use. Additionally, since electric THW systems can be relatively small, you can put them right in the bathroom of where the hot water is needed (point of use), eliminating the seconds (or minutes) it takes some systems to get the hot water from the furnace to where it is needed. They will be around 20% cheaper than an electric tank unit.

Other ways to save on energy costs with water.

1) Buy a decent low-flow showerhead. I have ones available that use 1 gallon per minute (and feel like a real shower instead of feeling like walking under dripping trees after a rainstorm) as opposed to the standard 2.5 + gallons per minute. Using that low flow showerhead saves 60% of your heating costs right there.

2) Buy faucet aerators that reduce the amount of water that flows out of your faucet. Many faucets run at full blast, wasting water (and heat) unnecesarily.

3) Get a "toilet tank bank" to reduce the amount of water used in a flush. Better yet, get a composting toilet and reduce water use 100% in your toilet. Clean, easy to use, and odorless (there is a fan drawing air into the toilet and out a vent pipe).

4) Rainbarrels - do you use house water to water your lawn or garden. You get charges both water and sewer charges for water that doesn't end up going down the sewer! Why not collect the (way too abundant) water off your roof and store for when we (or if we ever) get a dry spell.

More info on water saving and energy saving re: water at www.sustainabilitynh.com

donnamatrix · 07-30-2009, 02:06 PM

We have had the Rinnai tankless water heater now for two months. No problems whatsoever. We did have our gas company come out to perform a safety check and they recommended that we have the regulator upgraded to provide more capacity, which they did for free.

The delay for hot water is not objectionable. You learn to turn on the hot water a little before you actually need it.

Although this calculation is not entirely scientific, it looks like it is saving us about $25/month on the electric bill.

We would recommend this upgrade without hesitation.

hazmatmedic · 08-03-2009, 07:29 AM

I'm glad everything worked out the way you wanted. I have had my Rinnai for over 2 years and recommend them all the time, with the exceptions and disclaimers I have said previously.
Its good to hear your supplier checked out the installation and installed a higher volume regulator for no charge. Good business.

ishoot308 · 08-11-2009, 09:15 AM

Dr Green's post above gives some excellent advice. I would like to point out however that most low flow shower heads are "aerating" which means they introduce air thereby causing the smaller water droplets to cool off much quicker. So yes, in a sense you are using less water but you could be using more hot water.

It's best to find a low flow shower head that is non aerating for maximum energy efficiency and water conservation, such as these...

http://www.nuprana.com/HE_Handheld_S..._p/n2945ch.htm

FWIW;

Dan

Dr. Green · 08-12-2009, 09:39 AM

The type I sell is a Bricor.

See: http://www.bricor.com/

They are pricy (starting at $62) but top quality and in my mind the best on the market (which is why I carry them). Many people (myself included) who have tried them say they feel like a real shower, not like you are under dripping trees after a rainstorm - a common complaint about low-cost low-flow showerheads.

05-05-2009, 12:42 PM	#1
donnamatrix Senior Member Join Date: Apr 2004 Location: Moultonboro Posts: 833 Thanks: 24 Thanked 258 Times in 120 Posts	Installation of Tankless Water Heater We are contemplating the installation of a Rinnai tankless water heater to replace the electric storage water heater that was originally installed in our home. We have received estimates from several area companies for the purchase and install of the unit. Bay Street Discount in Ossipee has tendered an attactive estimate for the unit and has recommended a plumber to install the unit. Has anyone had any dealings with Bay Street Discount on this sort of installation? We would be very interested in hearing any comments on this company and on your experiences with these tankless water heaters.

05-05-2009, 02:27 PM	#2
fatlazyless Senior Member Join Date: Apr 2004 Posts: 8,734 Blog Entries: 1 Thanks: 300 Thanked 1,005 Times in 733 Posts	Rinnai builds quality that lasts and lasts and lasts. Don't have a Rinnai water heater but do have a couple Rinnai hot air heaters. Amerigas-Laconia is a Rinnai dealer and does installations. If you have them do the install then you get the item-install-propane all from the same company and could be they offer you a deal on a propane pre-buy deal, too. Plus, right now is a slow time of year for Amerigas-Laconia. For purchasing the Rinnai item without installation, www.alsheating.com in Brunswick Maine has low prices. __________________ ... down and out, liv'n that Walmart side of the lake!

05-05-2009, 04:06 PM	#3
jmen24 Senior Member Join Date: Feb 2009 Posts: 1,139 Thanks: 223 Thanked 319 Times in 181 Posts	Tankless Information One side of the coin, A tankless water heater saves energy by only heating water that you are using at that time without any storage of unused energy. If you do not demand hot water on a regular basis or for a continued amount of time, you can save some money on energy bills by not wasting energy to keep water warm until you use it. They take up no floor space and are very neat and tidy mounted on a wall. The other side of the coin, A tankless water heater has to see a call for water before it will start to produce hot water. If you take prolonged showers the unit will run the entire time to keep up with demand, if more than one shower is used at a time (or a performance shower) volume may overwelm its ability to satisfy both locations. The startup pause (waiting for water to arrive) is slightly longer than a storage tank heater, but probably not noticable to most. May not be DIY friendly depending on owners ability to troubleshoot. Writers conclusion, These units fall under the same catagory as the flourescent light bulbs that are touted as green. The application needs to fit the use. Flourescent bulbs only consume less energy if they are in locations that a light will remain on for a long enough period of time to offset the greater amount of energy it takes to start one up. Tankless water heaters work on the opposite thinking, you will save more money if you do not have to use it all the time. When customers of ours are looking into the possibility of adding one of these units we will sit down and present the above information and then ask then what there daily hot water usage is, this is not an exact number thing, just how many showers a day, dishwasher usage per week, washing machine usage per week and then we add up all these items to get an idea of how long this unit will run on an average day. Compare the Btu's of the tankless against the storage heater to get an idea of consumption for each unit, and that is your answer of if it works for you. Your local plumbing supply company have people on staff that can do these calculations for you if you provide the water usage in GPM of each faucet and water consuming appliance as well as duration used along with frequency. They typically sell both so there is no pressure to sell you on one vs the other. We have installed many of these units in our customers homes that are second and third homes that do not get rented at all and see use only a few days out of the year. We do not put many in primary residences due to the amount of water used on a daily basis. I hope that helps and was understandable. One more thing, you may want to compare an electric water heater (being that is what you have now) against a gas unit first to get the better of the two before moving on to compare with the tankless. Last edited by jmen24; 05-05-2009 at 04:09 PM. Reason: One more thing

05-06-2009, 07:03 AM	#5
SIKSUKR Senior Member Join Date: Apr 2004 Posts: 5,075 Thanks: 215 Thanked 903 Times in 509 Posts	Not sure what jmen is talking about.I have never had any issues in reguard to demand with my tankless.Unlimited hot water. __________________ SIKSUKR

05-06-2009, 07:44 AM	#6
jmen24 Senior Member Join Date: Feb 2009 Posts: 1,139 Thanks: 223 Thanked 319 Times in 181 Posts	Energy Consumption, not hot water supply I am talking about energy consumption to make the same amount of water. Your tankless has an output rating of GPM, you take your GPM output and convert to btu's used to heat your output GPM to get the overall efficiency of your application. If you read my post completely, I stated that it all depends on usage and energy consumption, not everyone is going to demand the same amount of water. For an example, in a recently completed project, a 6'x5' performance shower was added in an existing system. Either way an upgrade was needed as the 12 shower heads and body sprays used 11GPM. That required the use of 380gal of storage to satisfy demand. A tankless unit would not even come close to providing the amount of GPM's needed to satisfy demand even if it was solely for that shower, not to mention it would tax the well pump for supply, because that runs the whole time as well. Hopefully that illustrates my point a little better.

05-06-2009, 06:36 AM	#4
dpg Senior Member Join Date: Apr 2004 Posts: 2,591 Thanks: 150 Thanked 229 Times in 166 Posts	jmen24 - then again if you do not call for hot water to much and have a storage tank isn't it a very minimal cost for it to just there "maintaining" the temp for the water it's holding?

05-06-2009, 07:53 AM	#7
jmen24 Senior Member Join Date: Feb 2009 Posts: 1,139 Thanks: 223 Thanked 319 Times in 181 Posts	dpg You are correct in that is costs more to make hot water than it does to maintain hot water, but a fair amount of our clients only come up a few weekends out of the year and that includes winter and they typically shut down the water system to prevent massive flooding in the winter if the system has a freeze up. In those situations we recommend the tankless, as the hot water is right there when then come up and want to have a shower right off.

05-06-2009, 04:51 PM	#10
BlackeyCoveR Junior Member Join Date: Oct 2008 Posts: 3 Thanks: 1 Thanked 0 Times in 0 Posts	Tankless Water Heater Vs Electric I did the same comparison and ended up staying with the electric water heater. I looked at overall energy consumption, and volume of water we need (family of 5 plus frequent guests). Although we're at the lake most of the summer, off season not so much. So with electric, I hit the breaker every time we leave and draw no electricity. I was not able to shut off if I went with gas.

05-07-2009, 07:18 AM	#11
hazmatmedic Member Join Date: Jul 2008 Posts: 47 Thanks: 6 Thanked 5 Times in 4 Posts	Jmen24 with good info I can help with the line sizing and regulator. Most regulators provided by your lp supplier will handle the increase in the btu load of the Rinnai, but if it didn't, they would provide a higher volume regulator for your needs. The line size is a different story and thats why having your propane supplier provide the Rinnai and installation of that product is probably the most cost effective, because they can do the whole job. Still get a quote from your supplier. The line size calculation isn't as complicated as Jmen24 leads you to believe. The NFPA code books provide that info or most technicians have a handy pocket sized book with the info. The Rinnai recommends the minimum of 3/4" IPS (iron pipe size) for propane supply, but that may have to be increased if it is a long distance from the point the gas supply enters your home. The other questions regarding line size was standard gas H2O heaters and gas ranges. "Typical" gas ranges are @ 60,000 btus and "typical" H2O heaters are @ 40,000 btus. The standard Rinnais are @ 200.000 btus and this is why it requires a larger line. The on-demand water heaters are not really for larger homes (more than 2 bathrooms), but are really ideal for smaller second homes. That is based upon some of the information that was provided by Jmen24.

The Following 2 Users Say Thank You to hazmatmedic For This Useful Post:
jellybean (07-16-2009), Mee-n-Mac (05-07-2009)

05-07-2009, 07:53 AM	#12
jmen24 Senior Member Join Date: Feb 2009 Posts: 1,139 Thanks: 223 Thanked 319 Times in 181 Posts	Thanks to Hazmatmedic Thanks for the line sizing info. I do not feel qualified to list line sizing and regualator sizes as I am not an installer, I leave those requirements to the specialized pros. I want to make sure that I am clear in not selling one unit over the other, the tankless systems are very good, just make sure it fits your lifestyle and needs.

05-07-2009, 08:29 AM	#13
John E Senior Member Join Date: Dec 2006 Posts: 59 Thanks: 2 Thanked 8 Times in 5 Posts	I can't see any reason not to use the Rinnai aside from initial cost. I'm wiring a large condo project and they are using the Rinnai as their choice of water heater. 2 Bed/ 2 bath units.

05-07-2009, 08:37 AM	#14
wifi Senior Member Join Date: Jul 2007 Location: Lakes Region Posts: 1,321 Thanks: 282 Thanked 287 Times in 169 Posts	200K BTUs... Yikes. Wonder if you could put a heat exchanger on it to recover some of the heat for the house/basement or what ever?

05-07-2009, 08:50 AM	#15
ishoot308 Senior Member Join Date: Feb 2008 Location: Gilford, NH / Welch Island Posts: 6,226 Thanks: 2,382 Thanked 5,275 Times in 2,049 Posts	I'll let you know... I'm having a Rinnai installed in my camp in a week or two and will report back as to it's effectiveness. I have a couple of friends who have snowmobile camps in Pittsburgh New Hampshire that use Rinnais and absolutely love them. I have rarely, if ever, heard anyone who has a Rinnai say anything but positive comments. Hopefully I will be the same! Dan

05-07-2009, 10:01 AM	#16
jmen24 Senior Member Join Date: Feb 2009 Posts: 1,139 Thanks: 223 Thanked 319 Times in 181 Posts	Rinnai is one of the easiest companies to work with regarding any issues, if you have them. They are a good choose if you are thinking of installing any type of system that they produce, tankless, monitor, etc.

05-07-2009, 12:04 PM	#17
upnorth Senior Member Join Date: Jan 2005 Posts: 64 Thanks: 0 Thanked 2 Times in 2 Posts	Copied from my post a few months back... We also installed a propane-fired tankless heater and I love it. Water is very hot and we've never run out -- even with multiple simultaneous showers. The builder recommended we go tankless and the cost differential over a propane fired hot water heater was only $170. Interestingly, when we tried to estimate what level we ought to be for propane pricing (per the deal with Our Town and Eastern propane) -- this being our first year with a new house -- the customer service rep commented that the Rinnai Tankless is very efficient and hardly enters their calculus. On the downside, every single time the hot water is turned on at the faucet for even a moment, the tankless fires up and you can hear it in certain areas of the home -- I'm sure I'm the only one that notices... I do notice a delay, but it's really not that long, maybe 30 sec?

05-07-2009, 12:24 PM	#18
Island-Ho Senior Member Join Date: Apr 2004 Posts: 176 Thanks: 19 Thanked 14 Times in 11 Posts	Comment & Question I would hope that the unit is designed so that a very high percentage of that 200K BTU goes into heating the water and that there is very little wasted to recover for space heating, although you might get a little out of the vent flue. I am considering using a tankless heater downstream from a solar hot water system. Does anyone know if the Rinnia fires up based on incoming water temperature or simply turns on when the water starts flowing? Obviously the second scenario would be undesirable if the incoming water is already hot enough! Currently my solar heated water flows into a backup gas fired water heater, but I would like to eliminate having to keep that tank warm all the time when there is plenty of solar heated water available.

05-07-2009, 12:57 PM	#19
wifi Senior Member Join Date: Jul 2007 Location: Lakes Region Posts: 1,321 Thanks: 282 Thanked 287 Times in 169 Posts	This ought to be easy to figure out BTU = heat required to raise one lb of water 1 degree F Water weights about 8 lbs/gallon. Lets guestimate we start at 50 degrees and want to get to 120 degrees. This is a 120-50=70 degree rise times 8 lbs/gallon = 560 BTUs to raise one gallon of water from 50 to 120. So, 3 gals/min = 1680 BTUs/minute times 60 minutes = 100,800 BTUs per hour. Efficiency is ~50%? Hmm... where am I wrong ?

05-07-2009, 05:17 PM	#21
wifi Senior Member Join Date: Jul 2007 Location: Lakes Region Posts: 1,321 Thanks: 282 Thanked 287 Times in 169 Posts	Jmen24 Thanks for the clarification

05-21-2009, 04:23 PM	#22
donnamatrix Senior Member Join Date: Apr 2004 Location: Moultonboro Posts: 833 Thanks: 24 Thanked 258 Times in 120 Posts	Installation scheduled for next week After multiple quotes and discussions with various suppliers and contactors, we have decided to move forward and have our tankless water heater installed next week. I was amazed by the range of quotes (40%) we received for the same Rinnai unit and same installation. I did find out that, in addition to the 30% tax credit from Uncle Sam, we should qualify for a $300 rebate from the Propane Gas Association of New England. Together, these credits/rebates should pay for about 50% of the total bill. Thanks for all the good feedback and advice. I will keep you posted as to our experience.

05-28-2009, 11:13 AM	#24
donnamatrix Senior Member Join Date: Apr 2004 Location: Moultonboro Posts: 833 Thanks: 24 Thanked 258 Times in 120 Posts	Heater is installed! Our new Rinnai tankless heater was installed yesterday. So far, so good. No big issues during the installation. Since the heater draws very little juice, we have added it to the generator transfer panel. So now, we will have hot water when we have a power outage and are running on our generator. The delay in getting hot water is noticable, but not much more than what we had before. All in all, a good experience.

05-28-2009, 12:53 PM	#25
jmen24 Senior Member Join Date: Feb 2009 Posts: 1,139 Thanks: 223 Thanked 319 Times in 181 Posts	Glad to hear your install went well, having the unit on the Generator is a great idea and will come in handy when you need it.

07-07-2009, 08:01 AM	#26
ishoot308 Senior Member Join Date: Feb 2008 Location: Gilford, NH / Welch Island Posts: 6,226 Thanks: 2,382 Thanked 5,275 Times in 2,049 Posts	As promised I am reporting back regarding the recent installation of my on demand water heater. First off let me state that it is not a Rinnai, it is another brand made by "State Water Heaters". It looks and works exactly the same as a Rinnai brand however. It's been installed in my camp now for about two weeks and this past weekend we really had an opportunity to put it to the test. We had six guests plus my wife and I all using hot water for showers, laundry, etc. Many times there were two showers going at once! This thing never hicupped once and worked flawlessly. I am super impressed at its performance and at how quiet it is! I have read some previous posts regarding the wait for hot water, but I am not experiencing this. The wait for hot water as the cold water in the plumbing lines between the heater and faucet is removed is there, but that is standard with any water heater and is not a factor whatsoever. Previously we had a small electric water heater and it could have never kept up this past weekend. I can't really comment on the cost to run as it's simply too soon but at the end of the season I will report back. So far we absolutely love the on demand water heater! Dan Last edited by ishoot308; 07-07-2009 at 09:19 AM. Reason: Spelling!

07-07-2009, 11:50 AM	#27
Dr. Green Member Join Date: Mar 2009 Posts: 38 Thanks: 0 Thanked 3 Times in 3 Posts	Note: This is not a disinterested post. I own a store in Laconia "Sustain Ability" selling solar hot water systems, and tankless hot water - both propane and electric. The cheapest way to heat water in the long term (even in the Lakes Region) is solar hot water (given you have sufficient solar access. Over time, it will be cheaper than even tankless water heaters (THW). If needing hot water only on a seasonal basis (i.e. - NOT winter), a flatplate system is cheapest, and certainly adequate. If wanting hot water throughout winter, an evacuated tube solar hot water system is better, due to the superior winter performance of the evacuated tubes. The next cheapest way is propane (or natural gas if you have it) tankless hot water whole-house systems. They should save 25% or more over an electric water tank, since they heat water only when you need it. Next cheapest is an electric point of use tankless hot water system. If you have simple needs, many propane systems will be too big (they will work fine, but will be like having a pick-up truck instead of a SMART car). While electric THW systems use much more power than an electric tank system while heating the water, they only heat it during use. Additionally, since electric THW systems can be relatively small, you can put them right in the bathroom of where the hot water is needed (point of use), eliminating the seconds (or minutes) it takes some systems to get the hot water from the furnace to where it is needed. They will be around 20% cheaper than an electric tank unit. Other ways to save on energy costs with water. 1) Buy a decent low-flow showerhead. I have ones available that use 1 gallon per minute (and feel like a real shower instead of feeling like walking under dripping trees after a rainstorm) as opposed to the standard 2.5 + gallons per minute. Using that low flow showerhead saves 60% of your heating costs right there. 2) Buy faucet aerators that reduce the amount of water that flows out of your faucet. Many faucets run at full blast, wasting water (and heat) unnecesarily. 3) Get a "toilet tank bank" to reduce the amount of water used in a flush. Better yet, get a composting toilet and reduce water use 100% in your toilet. Clean, easy to use, and odorless (there is a fan drawing air into the toilet and out a vent pipe). 4) Rainbarrels - do you use house water to water your lawn or garden. You get charges both water and sewer charges for water that doesn't end up going down the sewer! Why not collect the (way too abundant) water off your roof and store for when we (or if we ever) get a dry spell. More info on water saving and energy saving re: water at www.sustainabilitynh.com

07-30-2009, 02:06 PM	#28
donnamatrix Senior Member Join Date: Apr 2004 Location: Moultonboro Posts: 833 Thanks: 24 Thanked 258 Times in 120 Posts	Successful installation We have had the Rinnai tankless water heater now for two months. No problems whatsoever. We did have our gas company come out to perform a safety check and they recommended that we have the regulator upgraded to provide more capacity, which they did for free. The delay for hot water is not objectionable. You learn to turn on the hot water a little before you actually need it. Although this calculation is not entirely scientific, it looks like it is saving us about $25/month on the electric bill. We would recommend this upgrade without hesitation.

08-03-2009, 07:29 AM	#29
hazmatmedic Member Join Date: Jul 2008 Posts: 47 Thanks: 6 Thanked 5 Times in 4 Posts	Also happy I'm glad everything worked out the way you wanted. I have had my Rinnai for over 2 years and recommend them all the time, with the exceptions and disclaimers I have said previously. Its good to hear your supplier checked out the installation and installed a higher volume regulator for no charge. Good business.

08-11-2009, 09:15 AM	#30
ishoot308 Senior Member Join Date: Feb 2008 Location: Gilford, NH / Welch Island Posts: 6,226 Thanks: 2,382 Thanked 5,275 Times in 2,049 Posts	Good Advice Dr Green's post above gives some excellent advice. I would like to point out however that most low flow shower heads are "aerating" which means they introduce air thereby causing the smaller water droplets to cool off much quicker. So yes, in a sense you are using less water but you could be using more hot water. It's best to find a low flow shower head that is non aerating for maximum energy efficiency and water conservation, such as these... http://www.nuprana.com/HE_Handheld_S..._p/n2945ch.htm FWIW; Dan

08-12-2009, 09:39 AM	#31
Dr. Green Member Join Date: Mar 2009 Posts: 38 Thanks: 0 Thanked 3 Times in 3 Posts	The type I sell is a Bricor. See: http://www.bricor.com/ They are pricy (starting at $62) but top quality and in my mind the best on the market (which is why I carry them). Many people (myself included) who have tried them say they feel like a real shower, not like you are under dripping trees after a rainstorm - a common complaint about low-cost low-flow showerheads.