Minor water pump issues

[Guest]

OK, water pump comes on briefly for about 2 to 5 seconds about every 2 hours, bilges checked and dry. Been like this for about 2 months, could it be related to heating the boat (radiators etc.) no issues last year although this year I'm keeping the boat slightly warmer, or could it be signs of pump failure? Absence of water where I don't want it to be has flummoxed me.

[Detling]

Do you have a calorifier which is heated by a back boiler or diesel heating? if so the heating could be going on and off with the thermostat or timer and the calorifier spits a little bit, out of the Pressure Relief Valve each cycle thus drawing a little bit more cold in every time, the PRV should be plumbed to drain into the bilge by the stern gland or overboard. 

[Tony Brooks]

If the PRV that is normally around the calorifier area is not weeping I suspect valves in the pump may be back leaking a litte.

[mrsmelly]

12 minutes ago, StationMaster said:

OK, water pump comes on briefly for about 2 to 5 seconds about every 2 hours, bilges checked and dry. Been like this for about 2 months, could it be related to heating the boat (radiators etc.) no issues last year although this year I'm keeping the boat slightly warmer, or could it be signs of pump failure? Absence of water where I don't want it to be has flummoxed me.

They dont always fail in an obvious manner. It could well be an internal fault with no leaks. I know this as mine was still working but seemed to take longer to pressurise so I fitted a new one a couple of weeks ago. I opened the original one up and it was full of water where the motor bit is yet was still running by some miracle, yet not leaking out anywhere. There is a thread I started somewhere re my pump not working right and some pictures of the failed pump.

[Guest]

Actually the other issue is that sometimes the pump doesn't come on if I turn on the hot water (needs a mixture of both hot and cold if that happens) - will search for Mr Smelly's thread.

 

ETA - will work out what the pressure relief valve goes/does as well.

Edited December 8, 2019 by Guest