# Water heater gas valves



## 504Plumber (Jan 26, 2011)

Lately we have been plagued with bad gas valves on water heaters, is there a way to test them while still on the heater or is it a light and wait scenario, would love to know if they made a tool for it.


----------



## skitian (Apr 5, 2011)

You can test the outlet pressure of the gas valve, and there is a coupling to put between the valve and thermocouple to measure milliamps, to make sure its working properly.


----------



## 504Plumber (Jan 26, 2011)

skitian said:


> You can test the outlet pressure of the gas valve, and there is a coupling to put between the valve and thermocouple to measure milliamps, to make sure its working properly.


Guessing game goes on then, a lot of what we are seeing is the valve working right then solenoid ( for lack of a better word, brain is shot) closing and shutting heaters down at random times.


----------



## skitian (Apr 5, 2011)

If I remember correctly that's part of the testing the milliamps with the extra component between the gas valve and the thermocouple. I have the stuff at work, I'll have to check it out tomorrow. What brand of heaters and gas valves are you dealing with?


----------



## 504Plumber (Jan 26, 2011)

skitian said:


> If I remember correctly that's part of the testing the milliamps with the extra component between the gas valve and the thermocouple. I have the stuff at work, I'll have to check it out tomorrow. What brand of heaters and gas valves are you dealing with?


American/whirlpool and more and more rheem/ge happening. I don't own a milliamp tester for thermocouples, if I change it and it still doesn't stay on then I know the valve is dead (unless safety shutoff is dead.)


----------



## DUNBAR PLUMBING (Sep 11, 2008)

*Got a call this weekend for a new one not working*

One that I replaced as the older one had an issue with the internals of the flue chase rusting out.


The new one, a 75 gallon PowerVent stopped working this weekend for no reason.

I didn't even waste my time troubleshooting; gave it straight to the authorized rep. I'm not putting up with that nonsense after seeing how many of these are malfunctioning.


The beauty of not purchasing these ticket items. #winning


----------



## Plumber Jim (Jun 19, 2008)

504Plumber said:


> American/whirlpool and more and more rheem/ge happening. I don't own a milliamp tester for thermocouples, if I change it and it still doesn't stay on then I know the valve is dead (unless safety shutoff is dead.)


I am betting Robertshaw gas valves. I know American had a rash of bad valves, the died in about a year of operation. In the case of these even testing it with a meter when you installed it, It would not have told you the valve was going to go bad. any good meter will let you test milivolts.
what meter do you have?


----------



## 504Plumber (Jan 26, 2011)

Plumber Jim said:


> I am betting Robertshaw gas valves. I know American had a rash of bad valves, the died in about a year of operation. In the case of these even testing it with a meter when you installed it, It would not have told you the valve was going to go bad. any good meter will let you test milivolts.
> what meter do you have?


The only meter I own is an analog voltage meter. I didn't figure any voltage testing would show a problem. I know about the bad lot that came with most bfg/fg model heaters, pissing me off that I'm seeing them more on rheems. Can't wait for the new delta valves to screw up, those look like they will be fun to mess with.


----------



## Plumber Jim (Jun 19, 2008)

You might consider getting a good digital meter. Things are getting more electronic. I have a fieldpiece very nice meter.


----------



## 504Plumber (Jan 26, 2011)

Plumber Jim said:


> You might consider getting a good digital meter. Things are getting more electronic. I have a fieldpiece very nice meter.


I will soon, I tend to leave my tools (only the expensive ones re: 2 rigid 14" alum pipe wrenches ) behind quite often. I'm a little skittish with expensive tools.


----------



## sikxsevn (Jun 23, 2009)

I have a fluke. Its a good one, measures volts, amps, capacitance and temperature if you buy the probe. You can also get different test leads too, the ones I have are threaded, you can change from a needle point to a connector probe or an alligator clamp.

Anyways, I think a thermocouple should test at least 11 millivolts, at least that's what I've been told, I may be wrong. I held a lighter up to one and it got up to 20 millivolts. 

Oh, and did you know you can make a thermocouple tester out of an old control valve?


----------



## 504Plumber (Jan 26, 2011)

sikxsevn said:


> Oh, and did you know you can make a thermocouple tester out of an old control valve?


Do tell


----------



## sikxsevn (Jun 23, 2009)

Take the control valve off the old heater. On the back, there should be 4 screws holding on the part that screws into the tank. Take out those 4 screws, and gently pull out the (likely red) wires. There should be a little black thing with heat-shrink around it on attached to the wires. This would be the temperature overlimit cutoff. 

Once you get the wires loose, trace them back to the part of the control valve where the thermocouple screws in. Get that valve out of the control valve. Depending on the brand control valve, this valve will either be threaded in, pressed in, or held in with a retainer and bolt. State water heaters are threaded. 

Once you get this valve out, you should have this thing with red wires coming out of it on one end and a rubber seal on a spring on the other end and a little electromagnet on the middle. This valve gets pressed down when you light the pilot and then hold the button long enough for the thermocouple to warn up enough for the electromagnet to gold the valve open. 

So with this valve removed, attach a thermocouple to it and put some flame on the end of it. Push the spring down, and if the magnet holds it down it works. 

Pictures tommiortoe


----------



## Redwood (Sep 8, 2008)

said:


> I have a fluke. Its a good one, measures volts, amps, capacitance and temperature if you buy the probe. You can also get different test leads too, the ones I have are threaded, you can change from a needle point to a connector probe or an alligator clamp.


Fluke meters are nice but I prefer to avoid paying for the name...

I have an ExTech Multi Meter #380224 

Functions include: 

Phase: 3 phase rotation testing 45 to 450Hz, 80 to 480VA
Voltage: DC 2V, 20V, 200V, 600; AC 200V, 600
Capacitance: 20μ, 200μF, 2000μF, 20m
Resistance: 200, 2K, 20K, 200K, 2000K, 20M, 200M, 2000
Frequency: 10Hz to 100KHz (autoranging)
Temperature: Type K temperature measurements (-58 to 482°F/-50 to 250°C Probe Included
Continuity beeper, Diode test

That's a lot of meter for $130,


----------



## Tommy plumber (Feb 19, 2010)

Redwood said:


> Fluke meters are nice but I prefer to avoid paying for the name...
> 
> I have an ExTech Multi Meter #380224
> 
> ...


 




Yeah, but does it have a stop-watch?....:laughing:

just kiddin'.


----------



## Redwood (Sep 8, 2008)

Tommy plumber said:


> Yeah, but does it have a stop-watch?....:laughing:
> 
> just kiddin'.


No but if you pull your stop watch apart you can measure the frequency of the quartz crystal and find out if the watch is accurate.... :laughing:


----------



## eddiecalder (Jul 15, 2008)

The fieldpiece SC56 will do everything you will ever need. It is most likely overkill for most but it is under $200. I like it much more than the fluke 902. 






Temperature (°C and °F)
Duty Cycle (%)
Resistance (Ω)
Diode testing
Amperage (AC)
Voltage (DC)
Micro-amps (DC)
Inrush
Frequency (Hz)
Capacitance (MFD)
Continuity
Voltage (AC)
Clamp Frequency (Hz)
Non-contact Voltage (NCV)
True RMS


----------

