State/AO Smith 50 gal gas hot water heater temp problems

[nydiyer]

This is a 50 gal powervent with no pilot. Has the Honeywell valve. Basic model.

Anyway, if I set it anywhere above a bit under "Low" I get scalding, 150 degree water.
If I set it even a touch lower, I get luke warm, 100 degree water.

I don't even want to think about A/B/C

Recently it blew the relief valve, I want to get to the bottom of it.

I believe It is under warranty. I always had issues with the temperature, and the water was very hot, just learned to live with it. I flushed the system every few months.

I called AO smith, they told me it could be stacking (no, it will heat to 150 degrees on low with no water being used). Then they told me I may have venting issues that can cause this issue. I have 3 wide 90s and 10 feet of straight pipe, nothing crazy for a powevent. They said sometimes the vent can cause the water to get much hotter.

They pretty much told me the Honeywell thermostats never fail.

 

[Fitter30]

800-527-1953 a o smith is this the number you called? Ask if you could talk to a field tech. Thermostat sound like its going bad. hot setting 120* A 130*,B130*, C140*
877-841-2140 honeywell. Not sure if this will get you to w.h. gas valves

 

[Sponsor]

 

[nydiyer]

Yeah, I guess I have to call again. A local plumber said he would bet the valve with those symptoms, he said get them to send one under warranty he charges $200 to replace or you can drain the tank and DIY. He said he keeps Honeywell valves with the pilot in his truck, they always fail.

He said if there was a vent problem to heat water to 150 deg, there is thermal sensor that would shut everything down.

 

[nydiyer]

Called State, they are sending a new valve. They said they were surprised to hear scalding water below Low. That can't be stacking.

 

[Dj2]

"Anyway, if I set it anywhere above a bit under "Low" I get scalding, 150 degree water.
If I set it even a touch lower, I get luke warm, 100 degree water."

- With such a sensitive temp control valve, can you raise it to between 100* - 150* ?
Then see if it maintains that temp.
115* -120* is pretty good.

Meantime, call AO Smith and try to get another valve. Be a pest, to get rid of you, they'll send you one.

 

[nydiyer]

"Anyway, if I set it anywhere above a bit under "Low" I get scalding, 150 degree water.
If I set it even a touch lower, I get luke warm, 100 degree water."

- With such a sensitive temp control valve, can you raise it to between 100* - 150* ?
Then see if it maintains that temp.
115* -120* is pretty good.

Meantime, call AO Smith and try to get another valve. Be a pest, to get rid of you, they'll send you one.

Yeah, they sent a new valve. $12 for shipping, if not I have to run to some distributor.
last night I did a test.
Empty all the hot water in the tank (unplugged)
Set it to low (I would expect 115ish).
In the morning (no stacking), lets say my thermometer said I have well done beef. I tried an IR thermo too, it was in the mid 150s.

 

[Reach4]

In the morning (no stacking), lets say my thermometer said I have well done beef. I tried an IR thermo too, it was in the mid 150s.

Was that after you swapped temperature controls?

 

[Fitter30]

Wonder if the dip tube is screwed up. Dip tube forces cold water to bottom of tank usually a broke tube there isn't a lot of hot water. Two controls doing the same thing very unlikely with hot = 120* Have them send out a tech.

 

[nydiyer]

Was that after you swapped temperature controls?

No, I called them today and told them this. They said it sounds unusual. They are sending a valve.