Water heater bad?

Old 09-18-11, 06:44 AM
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Water heater bad?

My 75 gallon gas water heater is 10 years old. It works more or less. If I try to adjust the temperature, it seems to only work at certain settings (can't fine tune it). I have hot water almost always, but occasionally it will be cold or luke warm. This is not due to the tank being emptied.

It worked perfectly until maybe 6 months ago. I think that it could be a calcium build up around the thermostat or a bad thermostat. Is it worth trying to use vinegar or CLR to clean it? I have flushed it with water several times. Unfortunately, I didn't flush it for the first 9 years.
Old 09-18-11, 09:15 AM
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Flush or drain? There is a difference. Hopefully someone who is more versed in the process will answer
Old 09-18-11, 10:16 AM
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Gas ? Electric ? please tell us make/model of heater.

Isn't CLR poisonous? I wouldn't put anything like that into my water system!

Do you / have you ever hooked up a hose and drained the 'crud' from the bottom of the tank? This should be done like every 6 months or so... but if you haven't done it, and do it now, you will NOT get the drain to stop leaking afterward... so don't run and do it if you haven't, it won't help now.

A ten year old heater may be past it's expected lifetime already...
Old 09-18-11, 11:56 AM
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If its 10 yrs old and never been drained I would noy touch it. Most of the time when you drain the heater to get some sediment out they start leaking shortly after.

You could possibly change the gas valve if that is the issue. It sounds like it is. But the money you will spend you might as well put to a new heater.

75 gallon you must have a large tub in the home. And you did not say how the heater was vented.

This is a great deal IMO with free shipping.

FCG-75 - AO Smith FCG-75 - 74 Gallon ProMax High Recovery 6 Yr Warranty Residential Water Heater (Nat Gas)

Mike NJ
Old 09-19-11, 07:14 AM
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It is gas- Powerflex PVG62. Vented outside.

I've let all the water out the drain, then filled it part way and repeated several times. Not sure if that is draining or flushing. I didn't do it for the first several years though (not sure how many).

Since it still mostly works, I thought CLR might help. I agree that at 10 years it is not worth replacing expensive parts. I read online that CLR or vinegar can help. I figured it was worth spending $10 and an hour to try it before replacing the heater.

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