Shurflo water pump

[SmnByt]

The pump seems to take a long time to turn off when the cold tap is closed, It sounds like its labouring quite a bit and even sprang a leak from around the pump. it runs for about 30 seconds from turning the tap off, the next time maybe only 10 seconds, its quite variable...
I can understand it happening with the hot tap as it has to refill what I have used from the water heater

any Ideas??

 

[WoodlandsCamper]

I can understand it happening with the hot tap as it has to refill what I have used from the water heater

any Ideas??

Doesn't it pump cold water into the water heater to force hot water out therefore takes no longer? It's not like a domestic hot water system with a header tank.

 

[SmnByt]

I can understand it happening with the hot tap as it has to refill what I have used from the water heater

any Ideas??

Doesn't it pump cold water into the water heater to force hot water out therefore takes no longer? It's not like a domestic hot water system with a header tank.

Yes I suppose it does, there goes my theory, it does take a lot longer to shut off when using the hot tap,

 

[ProfJohnL]

Hi Smnbyt,

The leak symptoms you describe suggest to me the water pumps pressure switch may have become faulty and is allowing the cold water pressure to rise above the normal 0.7 to 1.0Bar. If the pressure switch fails to operate correctly, this type of pump is capable of producing dangerously high pressures, and this can lead to pipes and fittings and appliances being stressed and causing leaks. Check your pumps hand book as it may give instructions on how to reset your pressure switch.

Your water heater delivers hot water by displacement. You have to pump cold water in to get hot water out. The heater is designed to keep a small air cap in the tank to allow for the expansion of the water when it is heated. This can cause a rise in hot water pressure over the cold supply, and when you turn on a hot tap you will often get a surge water before the pump kicks in. When you turn the hot tap off, the pump will run for a little longer to re-establish the pressure in the tank, but this should not be more than about 5 to 10 seconds tops.

 

[RayS]

Another possibility is that your taps have filters built in to the nozzles (e.g. Whale taps) and that one is more blocked than another such that the pressure drop when using them is different hence the pump runs for different times after switching the taps off. This certainly happened with my Avante 540 in a hard water aream and was cured completely by removing and descaling the filters in the tap nozzles.

 

[SmnByt]

A new pump sorted it out, a bargain at £49 incl shipping, (Shuflo Trail King 7, 20psi) its now lovely and quiet and only operates when the tap is on, obviously... and takes a fraction of a second to switch off once the tap is turned off

 

[ProfJohnL]

Good news!