Hot water heater

Typically with 70*F water supply an RV water heater will heat to shutoff temp in 30 mins. on electric heat element and 20 mins on propane heat.
(The colder the water supply...the longer heating to shutoff temp)

Normal t-stat preset temp is 140*F
ECO t-stat (high temp) preset is 180*F

Hot water is not intended to be used 'straight' from faucet/shower......it s intended to be tempered with cold water my user at faucet.
This allows longer hot water from a smaller size/capacity water heater.


Longer heating times and really, really hot water could mean that normal temp t-stat is not opening and water is heating until ECO t-stat opens shutting down heating process.
But if that was happening......
Suburban Brand would not refire until you 'reset' the ECO by pushing reset button
Atwood ECO will 'auto reset' when temp drops but you would get a 'fault' light on switch panel that will stay on until you turn switch off then back on.

You can test water temp........
After heating cycle......run straight hot from nearest faucet into a mug and take water temp with instant read thermometer.

CAUTION: water can scald at 125*F----water temp should be close to 140*F (or 180*F) SO YOU CAN GET INJURED.
Testing water from faucet will have slightly lower temp then water in WH tank........BUT is safer than trying to get sample from the Pressure/Temperature Relief Valve
CAUTION>>>>>>>>>>>>>>

rutzbeck, I think what you are experiencing is typical when using propane. I think if you used 120v or 12v, it would take longer.

I typically will turn on the water heater 30 to 45 minutes before I need hot water. I do not leave it on all of the time, unless it is exceptionally cold.

Wayne

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