RUUD PVP75E-1 Gas Water Heater short cycling

Following links might help
http://waterheatertimer.org/troubleshoot-hot-surface-igniter.html
http://waterheatertimer.org/troubleshoot-gas-water-heater-thermostat.html#thermostat

Pilot could be blocked pilot injector is very small on lpg heater
May also need new Piso igniter sparker

Generally, if a RV water heater is self igniting, then it is not designed to be lit manually. If you remove the outside vent cover door, then the unit can be observed. The self igniter should be visible at a point of where the pilot light is located. The problem with trying to light the water heater manually is that the circuit that activates the igniter also turns on the gas at the same time. If the igniter is not getting power, then most likely the valve to turn on the gas is not getting power either. If the problem is that the igniter itself has failed, then it may be possible, but unlikely, that with someone inside activating the turn on switch and a flame being applied to the pilot light area, at the same time, the pilot may light.

http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#igniter

http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent

Gene h

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Today's water heaters have sealed combustion chamber and piezo igniter.
If igniter is bad, then water heater will not light... replace igniter.
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#pilot
http://waterheatertimer.org/How-to-light-gas-water-heater.html

Gene h

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Reset button on gas water heater??
Usually there is not a reset button on gas water heater, which might explain why is doesn't move:

Do you mean the igniter button for lighting pilot?? The piezo igniter can go bad.

Copy following links for troubleshoot resources:
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent
http://www.thetankatwaterheaterrescue.com/forums/forum3/

Add comment with description of water heater, and more detail or call plumber.
Gene
h

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Copy following links
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#pilot
http://www.thetankatwaterheaterrescue.com/forums/forum3/

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

1) Lockout FV tripped
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html
2) Bad gas control valve:
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent

http://www.thetankatwaterheaterrescue.com/forums/forum3/

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Rheem-Ruud does not post service manuals.
Tank-type?
Copy following link to troubleshoot by type of gas control valve.
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent
Tankless? Don't buy a tankless.
http://waterheatertimer.org/Troubleshoot-Rheem-Tankless-water-heater.html

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

If thermocouple is from ordinary tank-type water heater, then it is a generic part with different lengths 15" 17" 21" 24" 30" available at hardware of home center.
I suggest reading manual for installation information, advisories, and required maintenance.
http://waterheatertimer.org/pdf/Rheem-Ruud-water-heater-parts-guide.pdf
http://waterheatertimer.org/How-to-install-gas-water-heater.html#clean

There are good utube videos on replacing thermocouple.
Tip of thermocouple has to be positioned in the pilot flame.
The heat on tip of thermocouple causes millivolts of electric current that travel back to the gas control valve and the electrical signal causes gas control valve to keep gas flowing down the pilot tube to the pilot light.
If pilot light blows out or if pilot tube is clogged and needs to be cleaned, or if gas valve has gone bad, then tip of thermocouple cools down and electric signal back to gas control valve causes gas control valve to shut off gas going to pilot.

When attaching thermocouple to gas control valve, it is finger tightened.
Be careful and do not cross-thread thermocouple. Just use your fingers to start the nut.
Finger-tighten thermocouple and then add 1/4 turn using small wrench.
The end of thermocouple has a small piece of insulation that isolates the electric current from body of gas control valve. If thermocouple is overtightened, the insulation is crushed, and electrical current millivolts short out and no signal reaches gas control valve, so gas control valve keeps gas turned off to pilot tube.

If this is a tankless water heater, then open following link with troubleshooting resources and contact information for Rheem.
http://waterheatertimer.org/Troubleshoot-Rheem-Tankless-water-heater.html

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