Truma Ultraflow smart switch 2nd Generation not activated by hot water taps

[soledancer]

Hi. The only way I can get hot water is to turn the tap(s) very slowly from cold to hot, which is a pain. If I turn the hot tap on, or move quickly from cold to hot "Clunk" the pump goes off. I have checked the non return valve, changed the pump, cleaned the tap heads, drained the system for air-locks (Several times), changed the filter, but still the problem persists. The caravan is a Coachman VIP 460/2 2016. The pressure switch is non-adjustable, and I believe it was only installed a year ago. I suspect the difference in pressure between cold and hot is more than the pressure switch can cope with, but this doesn't explain why the hot taps fail to activate it when turned on first. Any ideas/answers welcome. Does anyone know if this switch is standard, or did previous owner upgrade from a manual?

 

[Hutch]

Hi. The only way I can get hot water is to turn the tap(s) very slowly from cold to hot, which is a pain. If I turn the hot tap on, or move quickly from cold to hot "Clunk" the pump goes off. I have checked the non return valve, changed the pump, cleaned the tap heads, drained the system for air-locks (Several times), changed the filter, but still the problem persists. The caravan is a Coachman VIP 460/2 2016. The pressure switch is non-adjustable, and I believe it was only installed a year ago. I suspect the difference in pressure between cold and hot is more than the pressure switch can cope with, but this doesn't explain why the hot taps fail to activate it when turned on first. Any ideas/answers welcome. Does anyone know if this switch is standard, or did previous owner upgrade from a manual?

My 2013 Coachman 560 VIP has the NON adjustable pressure switch.

 

[IanB1485]

The hot and cold water water pipes are at the same pressure , provided by the water pump. the issue may be a faulty surge arrester but again thats on the common output from the pump , the only difference being the hot water system has more volume. As you have seemed to eliminated a lot of the components, then I would change the pressure switch for the Whale inline type which is adjustable

 

[Martin_E]

Possibly something in/under the tap cartridge, I had a vector tap that ran really slowly, the pump would switch on and off, I took the tap apart and in the valley under the cartridge I found some black plastic bits, pulled them out and refitted tap, tap now working as it should. No idea where the plastic came from🤔