Originally Posted by PaulK
Would anybody know if my 2007 378 should have one or more bypass valves? I found one by removing the round screw off cover, but antifreeze flowed into the water heater when I winterized. I searched with a flashlight and by sticking my arm into the compartment as far as I could, but couldn't locate any other valves.
A photo of what you found would be helpful.
If it is a lever type (single valve system) like below and you filled your hot water tank, the valve is either broken or your tank outlet check valve is bad.
If it looks like the "back of the tank" photo's valves (3 valve system), you did not find them all.
Lou and Laura with Bella - German Short Hair Pointer
2008 GMC Sierra 2500HD Crewcab SB Allison Duramax
2010 Flagstaff 8526RLWS - Superglide 3300
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