Water Heaters - Bad thermister in gas valve? 2001 AO Smith FCG-40
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ls3c6
10-01-09, 11:37 PM
I've experienced a lot of inconsistancy in temperature with my water heater since buying my home 8 mos ago, I thought I was experiencing a bad dip tube as I set the temperature to 140f or "B", but at the highest all I will get is 120... and probably due to deadband if I don't run hot water for ~12hrs i'm lucky to get 110.
So, to verify I set to 150F or "C", waited for the burner to turn off then measured the water temperature with the inlet supply line off both by draining some out of the bottom of the tank and also at a faucet, both produced 130F right after the burner turned itself off.
Does this mean my gas valve assembly needs to be replaced as the thermister isn't turning off at the desired temperature nor maintaining close to the temperature it's turning off at, or is there a way to clean/correct the existing one?
I've cleaned the burner ports, flushed the unit etc, i'm on untreated city water and there wasn't much sediment in the bottom of the tank, no odd smells in the water either, other than temperature regulation the water heater works properly and has an efficiency factor of .57 so a $65 gas valve is probably worth the time/money vs. a new 500+$ unit that won't be much, if any, more efficient.
*edit: looks like part number is 9004028205, cheapest place to buy?
So, to verify I set to 150F or "C", waited for the burner to turn off then measured the water temperature with the inlet supply line off both by draining some out of the bottom of the tank and also at a faucet, both produced 130F right after the burner turned itself off.
Does this mean my gas valve assembly needs to be replaced as the thermister isn't turning off at the desired temperature nor maintaining close to the temperature it's turning off at, or is there a way to clean/correct the existing one?
I've cleaned the burner ports, flushed the unit etc, i'm on untreated city water and there wasn't much sediment in the bottom of the tank, no odd smells in the water either, other than temperature regulation the water heater works properly and has an efficiency factor of .57 so a $65 gas valve is probably worth the time/money vs. a new 500+$ unit that won't be much, if any, more efficient.
*edit: looks like part number is 9004028205, cheapest place to buy?
ls3c6
10-05-09, 10:07 AM
well forget it, putting in a bradford white unit today