R-27 Hot Water Heater alternating hot/cold/hot/cold

[WA6BTK]

We have a problem that materialized about 4 days ago while cruising. Suddenly one day, the water coming from either faucet (galley or head/shower) began cycling as the water came out the faucet. It didn't matter if we were plugged into shore power or letting the engine do the water heating. The end result was after the faucet handle was set for a comfortable temperature, water coming out would be comfortable for 3 seconds and then when the pressure pump would activate, the water would go very hot for 3 seconds. When the pump stopped for a few seconds, the water would go very cold, the pump would resume, and the water would go from very cold to very hot. We are at a loss as to why this happening. Have any of you experienced this, or can think of a reason why this is happening? Every day in the past 4 days, the situation remains the same. Thank you for any feedback.

Sue

 

[knotflying]

Not sure, but if you have and anti -scald valve it may be defective and is reacting to the change of water pressure.

 

[WA6BTK]

This makes some sense. Thank you. Will check on that tomorrow when it's light out. One other thing that I forgot to mention is that about the time we noticed the problem, it was at a time when the electric water heater was ON and in taking a shower, we ran out of fresh water. Right after that, it dawned on us that the water heater was still ON with no water present. We turned it off and topped off the tank. Would this still lead you to believe it could be the anti-scald valve or does something else come to mind. --Sue

 

[knotflying]

It could be possible that sediment and tank shavings got stuck in the valve. If you can, you can always try to bypass the valve and see what happens. Just don't scald yourself. I am not sure if the valve is serviceable, if the problem is the valve. You may just have to buy a new valve.

 

[WA6BTK]

Thank you for more perspective. After breakfast, I'll start digging. Is the valve you mention easy to see/get to?

 

[baz]

Jim: I'm unaware of my R-25 (Classic) having an anti-scald valve. Is this new with the R-27 Maybe ? If my R-25 does have an anti-scald valve I'd sure like to know where it's located. Thanks... 🙂

 

[knotflying]

My tug is a 2011 and does not have one. It is my understanding, and I may be wrong, that later models have them. If it does have one it should be right off the hot & cold of the water heater.

 

[Irish Mist]

I had one on my 2011 R29 it is gone now had flow issues, all good now. Except hot water is very hot and you need to use caution ..