Empire RH65 B vent- Pilot goes out....Help

[Val]

Hello,
we have an empire RH65 propane B-vent heater and we replaced the thermocouple to try to correct the pilot problem but it didnt help...heater does the same thing.....

this is what happens....depress the pilot button to get started, but we light the pilot flame with a lighter because the piezo sparker has no wire. (this is a "used" heater which worked last year but gave trouble toward end of season. it had piezo ignitor broken when got it.)

but when you release the pilot button after depressing for well enough time..several minutes, the pilot goes out.Pilot will go out when you turn the knob to ON position to light main burner too. the pilot flame is big and blue and covers the thermocouple. There does not appear to be any "adjustment" on their placement anyway, they have a set bracket.

So...any ideas? is there some "magnet" in the valve body that goes bad, turning gas flow off? or does the crazy vent blocking "eco switch" go bad? if there was dirt in the pilot orifice...would that produce a poor pilot flame? The pilot flame is good size. The propane tank regulator, as far as I know is producing adequate gas pressure to the heater itself.

this seems to be a common problem with b-vents....any help on the specifics of this model would be very helpful. Thank you.

 

[DAKSY]

Can't talk to specifics on your particular model, but I have encountered this issue on older B-vents. Most of the time is was the age of the wiring in the circuit that detects an overheat condition thru a spill switch (snap disk). Look for a wire that comes off the back of the gas valve that (generally) will run up to a location above the firebox. The first thing I'd try is to jump the spill switch with a double male spade connector. If that works, the switch is probably bad. If that DOESN'T work, try replacing the wires to & from the spill switch. They are in a very harsh environment & the sheathing can fail & ground the circuit. If THOSE two fixes don't work, you may have a bad gas valve, altho that is pretty uncommon. What type of valve is it? The ID may let one of us know how to test it...

 

[Val]

Can't talk to specifics on your particular model, but I have encountered this issue on older B-vents. Most of the time is was the age of the wiring in the circuit that detects an overheat condition thru a spill switch (snap disk). Look for a wire that comes off the back of the gas valve that (generally) will run up to a location above the firebox. The first thing I'd try is to jump the spill switch with a double male spade connector. If that works, the switch is probably bad. If that DOESN'T work, try replacing the wires to & from the spill switch. They are in a very harsh environment & the sheathing can fail & ground the circuit. If THOSE two fixes don't work, you may have a bad gas valve, altho that is pretty uncommon. What type of valve is it? The ID may let one of us know how to test it...

Thank you for the info. the model is an RH65B-6, Propane gas, serial number 0407291571, manufactured in 04/06. The gas valve is a Mertix Maxitrol GV31.

Still having trouble with the heater. Jumped the "spill switch" or "eco switch" wires and also checked them for deterioration at the valve end but they are OK. The pilot light goes out when you release the pilot button. The pilot is a large blue flame and in contact with the new thermocouple. We even tried "pre-heating" the thermocouple with a small torch to speed up the process. When we did this, we were able to get the main burner to light but it only ran for about 5 minutes and then a big "click" and the burner shut off abruptly. Took the plastic cap off the valve body and found a round metal circle with +/- adjustment on it.....do you think this adjusts a solenoid shut off on the valve body? Can the valve body be bad...not necessarily the valve but does it have a magnet shut off inside. I have seen these pictured on parts breakdowns for the 25,000 and 35,000 BTU Empires....but not the 65,000 BTU parts breakdown. Thank you. Val

 

[DAKSY]

Maybe someone else can chime in on that particular valve, as I'm not familiar with it. How much of the Thermocouple (T-C) is in the pilot flame? Should be the top 3/8" of an inch. That +/ - may be be the pilot flame height adjustment screw for that valve. I'd try turning the screw 1/4 turn at a time TOWARD the + to see if you can get more millivolts out of the T-C...

 

[Heatsource]

http://www.mertikmaxitrol.com/pdfs/gv30_60/GV-CC-EN-07.2010.pdf
here is some basic info on the valve, and contact info for the maker....

 

[ajaynejr]

I am guessing that the problem is in the eco valve or assembly in the control box, not the part up in the flue.

 

[EmpireTech]

I can help answer your questions and give you some ideas of what to check. First is was built in Feb of 2004. From your description it is either a bad thermocouple or a bad valve. You can check the voltage off the thermocouple with a volt meter should be putting out about 17-24 milli volts with the pilot on. If you are good on that then its a gas valve. If it is low then its a thermocouple. The adjustment in the center of the valve is the manifold pressure adjustment. There is a pilot adjustment screw in the corner under that cover as well but if your pilot flame is as you say it should be good. The pilot orifice can pick up dirt and reduce the pilot flame as well.
My first thing to do would be to clean the pilot orifice by removing the orifice and blowing it out, polish up the thermocouple and then test it for voltage. If it is good then the cleaning was all that was needed, low voltage then replace the thermocouple. If the voltage is good and pilot is clean then it is time for a valve.