Hot water not as hot as it should be - is this the problem?

[syntax53]

New RV'er here. Our hot water is not as hot as it should be. At first I was doing research into how to adjust the thermostat on it but came to the conclusion that I have one that permanently set. However, most say it's set to 130 or 140 degrees, which it is definitely not.


I read somewhere about checking the bypass valves so I started poking around. The water heater is mounted under one of my dinette seats and after removing the panel tonight I found the attached image.


To me, that valve that connects the hot and cold should be closed, right? I think what's happening is when hot water is called for it's basically mixing the cold and hot?

[winniman]

Yes, the middle valve should be closed. It is for bypassing the heater when winterizing. It is then you close the other two valves, and open the middle one, therefore allowing rv antifreeze through the system without having to fill the hot water tank.

[l1v3fr33ord1]

syntax53-

Yes- close that valve.

Also make sure that your hot- and cold-water shower valves are shut off. Check the inside shower and the outside shower, if your trailer has one. Mixing can occur at these valves, too.

[Old-Biscuit]

Yes the center valve is the 'bypass' and should be closed


That Suburban Water Heater uses a pre-set t-stat that Opens at 130*F/Closes for heating at 100*F
The High Temp T-stat trips at 170*F and has to be manually reset (outside compartment above gas valve 'Push to Reset' --- Right side for the 12V DC/Propane


Nice that RV MFG installed the 3-valve system vs just i or 2 valves and 'check valves'
Shutoff valves unlike the cheap check valves rarely clog up/fail.
Normal Operation:

Cold In/Hot Out OPEN---Bypass Closed


Bypassed Operation:
Cold In/Hot Out Closed---Bypass Open

[Redapple]

Yes, valve connecting blue and red should be closed