On-Demand Has Some Drawbacks
We have an on-demand hot water heater (natural gas) and I'm not thrilled with it.
There is a delay after the water begins to flow, and it takes a while to heat up the exchanger before the water gets hot. As a result, you have to run the water for a long time before it's hot at the faucet. If you're just washing your hands, it takes too long.
When you shut off the water, the heat exchanger quickly gives up its heat. So when you turn the faucet back on, it's cold again and you have to wait.
You end up wasting a lot of water waiting for it to get hot.
If you are in the shower when someone starts up the dishwasher or washing machine, you get widely varying pressure, so temperature variation.
Finally, I think another thread mentioned that you cannot completely drain an on-demand unit to shut it down in the winter.
I can imagine a unit that addresses these complaints, but I don't think it's on the market yet.
|