Good to see some of the same faces knocking around on here - hopefully I can tease some knowledge out of their experienced heads
I have a Vaillant turboMAX Plus 837E combi (VUW GB362/1-5 R3) (GC# 47-044-028) that is playing up. On drawing hot water, the temperature on the boiler display rises extremely rapidly and results in an F22 code lockout*. On central heating, the radiators only just become warm and the boiler cycles more frequently than normal.
*From the manual: F.22 Dry fire protection. No water in appliance, pump cable defective, pump blocked or defective, pump output too low
A bit of numpty diagnosis later reveals that the pump is not spinning up although the shaft feels free and turns easily. So I drained down and pulled the pump head off (removed the 4 bolts).The impellor has a light black coating, but no major nasty build up. If I apply power to the pump head and manually set the impellor spinning it comes up to speed and stays spinning. It is however remarkably easy to stop spinning with a fairly light finger touch.
So the questions are - how much "oomph" should the pump have, should it be that easy to stop spinning? Or - is it just the capacitor that has given up the ghost so failing to kick the pump into life initially? Oh - and as I am no electronics engineer - does the capacitor only contribute to the inital start of the pump or does it also add some "oomph" when the pump is up to speed??
Other info that might be useful - the pump is type VP5/2 P/N 59866537 (Grundfos 161015).
Grateful for any advice (and grateful I remembered I had some thermal longjohns stashed away from years back!).
I have a Vaillant turboMAX Plus 837E combi (VUW GB362/1-5 R3) (GC# 47-044-028) that is playing up. On drawing hot water, the temperature on the boiler display rises extremely rapidly and results in an F22 code lockout*. On central heating, the radiators only just become warm and the boiler cycles more frequently than normal.
*From the manual: F.22 Dry fire protection. No water in appliance, pump cable defective, pump blocked or defective, pump output too low
A bit of numpty diagnosis later reveals that the pump is not spinning up although the shaft feels free and turns easily. So I drained down and pulled the pump head off (removed the 4 bolts).The impellor has a light black coating, but no major nasty build up. If I apply power to the pump head and manually set the impellor spinning it comes up to speed and stays spinning. It is however remarkably easy to stop spinning with a fairly light finger touch.
So the questions are - how much "oomph" should the pump have, should it be that easy to stop spinning? Or - is it just the capacitor that has given up the ghost so failing to kick the pump into life initially? Oh - and as I am no electronics engineer - does the capacitor only contribute to the inital start of the pump or does it also add some "oomph" when the pump is up to speed??
Other info that might be useful - the pump is type VP5/2 P/N 59866537 (Grundfos 161015).
Grateful for any advice (and grateful I remembered I had some thermal longjohns stashed away from years back!).