Water Heater pressure - Problem Solved
Thank you one and all for the assistance in solving this problem. The cure was to replace the expansion tank. Pressure is now 60 lbs and topping out at 65 when the water heater kicks in. The old expansion tank had a ruptured diaphram and all air had leaked out. Original text describing problem is shown below. Thank again. David
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We are experiencing intermittent rises in water pressure and am suspecting the water heater gas valve.
We noticed the water heater temperature/pressure relief valve venting so I replace that. The problem continued. I attached a water pressure gauge at the drain valve. The gauge has a high point needle and while the pressure read 60 psi at the time it showed 60 again the next morning but also indicated that it had gotten up to 160 psi had been reached during the night. Water company came out and tested and said there was 102 psi at the main line (before our regulator). We put in a new regulator, set it to 60 psi and again the next morning it showed 60 but a peak of 160 during the night. We had put a bucket to catch any water passing through the relief valve and water is present there.
I did turn up the temperature on the tank and it heated and shut off. I did that a second time and again it heated and shut off (no water passing through the relief valve either time nor a rise in water pressure.
My question is: Will a heater gas valve perform OK sometimes and then go wild and not shut off? This would overheat the water causing excessive pressure. However, wouldn’t the water pressure vent itself back into the street main at pressures over the 60 that the regulator is set at? There is no check valve that I am aware of in the system between the heater and the street main.
David
Thank you one and all for the assistance in solving this problem. The cure was to replace the expansion tank. Pressure is now 60 lbs and topping out at 65 when the water heater kicks in. The old expansion tank had a ruptured diaphram and all air had leaked out. Original text describing problem is shown below. Thank again. David
============================
We are experiencing intermittent rises in water pressure and am suspecting the water heater gas valve.
We noticed the water heater temperature/pressure relief valve venting so I replace that. The problem continued. I attached a water pressure gauge at the drain valve. The gauge has a high point needle and while the pressure read 60 psi at the time it showed 60 again the next morning but also indicated that it had gotten up to 160 psi had been reached during the night. Water company came out and tested and said there was 102 psi at the main line (before our regulator). We put in a new regulator, set it to 60 psi and again the next morning it showed 60 but a peak of 160 during the night. We had put a bucket to catch any water passing through the relief valve and water is present there.
I did turn up the temperature on the tank and it heated and shut off. I did that a second time and again it heated and shut off (no water passing through the relief valve either time nor a rise in water pressure.
My question is: Will a heater gas valve perform OK sometimes and then go wild and not shut off? This would overheat the water causing excessive pressure. However, wouldn’t the water pressure vent itself back into the street main at pressures over the 60 that the regulator is set at? There is no check valve that I am aware of in the system between the heater and the street main.
David
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