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Heating & Air Conditioning

Hot Water not hot enough when heat is on

13 years ago

Over the past few weeks I have noticed that I don't have enough hot water for a bath sometimes and am wondering if it has anything to do with my heat being on at the same time.

I have a forced hot air system and I know that the hot water heater sends water through the system and then the water is returned to the hot water heater.

I have my water heater (which is about 8 years old)turned up almost all the way and usually my water is borderline scalding when I just turn the hot on. The colder it is outside (and I live in CT so it's coooolllddd these days!), the higher I have to turn the water temperature so that I have enough. I understand that the cold water that needs to be heated up is colder than usual but if I have the hot water thermostat set to high, it should heat it up to the same temperature regardless of the starting temperature, right?

Anyway, I was wondering if the issue has something to do with the fact that I have my heat on more lately and maybe it has something to do with the majority of the hot water is being used by the furnace (which is about 15+ years old) so there's not enough left to run a very hot bath.

Thanks.

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Comment (1)

baymee
13 years ago
Your boiler will have an aquastat, and that stops the heating of the house so you have enough hot water at the bath.

Look at the temperature gauge on your boiler. It should not go below about 150 degrees on the dial. If it does, your aquastat may be faulty. If not, you might have a failing mixing valve, or a hot water coil (inside the boiler) that is being limed up and requiring replacement of acid cleaning.

If the water pipe is very hot before the mixing valve and very cool after the mixing valve, your valve might be failing.
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