Problem with water pump

[marioxp]

I have put  mixing valve on boiler to limit the temperature  of hot water. After that I have noticed  that  the water pump starts to work every 1-2 minute. I've also noticed that the water started to flow back out through the water inlet. What could be the cause of this situation? Water should  I do? Thank you.

[marioxp]

Please,

Could you tell me what is water path on Bavaria 36 2003.

I have two tanks of 150l, switch valve before pump (I think), water pump with some pressure reservoir...

I don't know where is splitting for cold water and water which is going to boiler.

Regards,

[Krumelur]

I think the owner's manual could help you identify where things are. I found this here in the forum: https://bavariayacht.org/downloads/manual/Bavaria%2036%202002%202003.pdf

[Yngmar]

Odd, as the only way the pump would cycle is if it loses pressure. If it's not going anywhere into the boat in the form of a leak, the only place it could be going without leaving a trace is back into the tank, via the pressure relief valve on the hot water tank. Have a look at that. We did have a failed one that was leaking, it was under a tenner to replace from a plumbing supplier. It's the one with a red plastic cap and the pressure where it opens is written on it somewhere. You can take the return pipe off and see if this is where the water goes.

We fitted a similar thermostatic mixing valve to the hot water tank and no problems.