Forum Discussion

dl68camper's avatar
dl68camper
Explorer
Nov 22, 2014

Hot water heater shutoff.

This is our second RV so I'm not completely new at this, but I don't understand the hot water heater shutoff/isolation method in this camper. There is only one shutoff valve that I can find in this camper. As a result the hot water heater back fills (through the hot side) with the pink stuff. I want to isolate the hot water heater when filling the system with the pink stuff so I don't have to use 10 gallons of the stuff. Did Cruiser forget a shutoff? What am I missing/overlooking???

This is the only shutoff/valve in/out of the hot water heater:


Also, In the photo I posted what direction would the water take with the valve in it's current position? (It will bypass the cold side of the hot water heater right?)

7 Replies

  • dl68camper's avatar
    dl68camper
    Explorer
    Nov 25, 2014
    Thanks Old-Biscuit! Confirmed yesterday the HW heater has check valve on hot side. This wasn't explained to me when we took delivery, previous camper had 2 shut offs and I wasn't thinking about this as an option at all. So to confirm I put the valve (in photo above) in bypass, pulled the HW heater plug (on outside of camper) and pressurized the system and no water came out the plug hole.

    I also need to add, for anyone reading this in the future, a correction to my opening post, the HW tank was not backfilling through the hot side as I incorrectly thought. I was operating the valve incorrectly. As others have enlightend me, the valve position as shown will fill the HW tank.
  • dl68camper's avatar
    dl68camper
    Explorer
    Nov 23, 2014
    I will test tomorrow at campsite and report back. I plan to switch to bypass with the heater plug out and I shouldn't get any water coming out once city water is hooked up and turned on.
  • newman_fulltime's avatar
    newman_fulltime
    Explorer II
    Nov 23, 2014
    dl68camper wrote:
    Old-Biscuit wrote:
    That is a 3 way cold inlet shutoff & bypass valve.

    Current position with handle parallel with bottom line is OPEN (allows cold water into bottom of WH Tank)

    Turn handle 1/4 turn......handle pointing up (parallel with vertical line) is BYPASS position. Stops water from going into bottom of WH and allows cold water to flow thru vertical line up to hot outlet line

    In hot outlet line (hidden in picture by flex duct) will be either:
    another valve (which has to be closed to stop flow backwards into WH tank via hot outlet)
    OR
    there is a check valve (internal of fitting on hot outlet)


    This sounds likely and I wasn't thinking about the possibility of a check valve on the hot side. That makes most sense. There is not a manual valve, I did check for that. Thanks much old-biscuit!


    oldbiscuit looks like you hit it spot on good job
  • K_Charles's avatar
    K_Charles
    Explorer
    Nov 22, 2014
    If you leave the Valve like that it will fill the heater thru the cold.
  • dl68camper's avatar
    dl68camper
    Explorer
    Nov 22, 2014
    Old-Biscuit wrote:
    That is a 3 way cold inlet shutoff & bypass valve.

    Current position with handle parallel with bottom line is OPEN (allows cold water into bottom of WH Tank)

    Turn handle 1/4 turn......handle pointing up (parallel with vertical line) is BYPASS position. Stops water from going into bottom of WH and allows cold water to flow thru vertical line up to hot outlet line

    In hot outlet line (hidden in picture by flex duct) will be either:
    another valve (which has to be closed to stop flow backwards into WH tank via hot outlet)
    OR
    there is a check valve (internal of fitting on hot outlet)


    This sounds likely and I wasn't thinking about the possibility of a check valve on the hot side. That makes most sense. There is not a manual valve, I did check for that. Thanks much old-biscuit!
  • newman_fulltime's avatar
    newman_fulltime
    Explorer II
    Nov 22, 2014
    if you turn the valve a quarter turn it bypasses the hwh there are check valves at the inlet and outlet sounds like the outlet one is stuck open
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Nov 22, 2014
    That is a 3 way cold inlet shutoff & bypass valve.

    Current position with handle parallel with bottom line is OPEN (allows cold water into bottom of WH Tank)

    Turn handle 1/4 turn......handle pointing up (parallel with vertical line) is BYPASS position. Stops water from going into bottom of WH and allows cold water to flow thru vertical line up to hot outlet line

    In hot outlet line (hidden in picture by flex duct) will be either:
    another valve (which has to be closed to stop flow backwards into WH tank via hot outlet)
    OR
    there is a check valve (internal of fitting on hot outlet)

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