On demand water heater

[Evans]

I have a 2017 Jayco Greyhawk with an on-demand water heater that provides dangerous hot water temperatures. I have it set to 104 and it’ll run up to 120F. It appeared to be intermittent so thinking it was varying water pressure at different parks, I put a pressure regulator on. Still intermittent. Any ideas?

[RogerR]

Sounds like the thermostat that regulates the heating coil is toast. Try a search online for the temperature regulator or thermostat for that specific model number. It may be a simple fix. Water pressure has no effect on the temperature, it should always shut off when it hits the set max.

Only took a second to find this youtube on it but you didn't mention the exact model so you may have to look further.

https://www.youtube.com/watch?v=juxiuD3taSw

[madmaxmutt]

Originally Posted by RogerR

Sounds like the thermostat that regulates the heating coil is toast. Try a search online for the temperature regulator or thermostat for that specific model number. It may be a simple fix. Water pressure has no effect on the temperature, it should always shut off when it hits the set max.

Only took a second to find this youtube on it but you didn't mention the exact model so you may have to look further.

The OP has a Girard on-demand WH, not a Suburban.

Originally Posted by Evans

I have a 2017 Jayco Greyhawk with an on-demand water heater that provides dangerous hot water temperatures. I have it set to 104 and it’ll run up to 120F. It appeared to be intermittent so thinking it was varying water pressure at different parks, I put a pressure regulator on. Still intermittent. Any ideas?

Are those numbers from the inside thermostat display? If not, it could be your outlet temp probe.

If you truly believe it is a pressure issue, fill your tank and try it with the pump.

[Evans]

Thank you sir. I have a Girard on-demand water heater (I believe). You’ve put me in a direction I’ll pursue (thermostat replacement). I’ll look for “how to instructions” for a Girard. Thanks again.

[Evans]

Originally Posted by madmaxmutt

The OP has a Girard on-demand WH, now a Suburban.



Are those numbers from the inside thermostat display?

If you truly believe it is a pressure issue, fill your tank and try it with the pump.

The temperature numbers are from a small panel near the bathroom sink. It’s at this panel where I can set the desired temperature.

[madmaxmutt]

Originally Posted by Evans

The temperature numbers are from a small panel near the bathroom sink. It’s at this panel where I can set the desired temperature.

That should mean the outlet temp probe is working, then. Try the tank/pump test and see if it results in the same temp variances.

[Thomson]

Bad thermostat or not affixed to the tank wall

[Evans]

Originally Posted by madmaxmutt

That should mean the outlet temp probe is working, then. Try the tank/pump test and see if it results in the same temp variances.

Thanks you sir. I’m not sure what a tank/pump test is (I know I don’t have a tank).

[madmaxmutt]

Originally Posted by Evans

Thanks you sir. I’m not sure what a tank/pump test is (I know I don’t have a tank).

Fill your fresh water tank and use the pump to verify whether it is a flow issue.

You can also call or message Girard tech support here.
https://girardgroupcompanies.com/con...hnical-support

For reference, the manual starts out with this pre-supposed statement about water flow.
"The RV’s cold water system deriving its water input from a pressurized (45 psi or greater) source such as a shore connection or an RV water pump connected to the RV’s fresh water storage tank. NOTE - A steady water low (no pulsating) will ensure a consistent temperature and performance."

[Evans]

Got it. I’ll give it a shot and let you know. Thanks sir.

[JimD]

I replaced that water heater in my 2017 Greyhawk with a tank model for the opposite reason - very poor hot water. I hated that thing. It wasted so much water trying to get the water to heat up. We dry camp mostly are have to be water and tank conscious.

I have attached the manual for the unit. Don't know if it will help or not.

[Evans]

Thanks JimD. I typically do not dry camp and when it works its sweet! I’d like to get it to consistently work if possible.