worcester bosch RD532i flow temp shoots up, cuts out no HWCH

[reapairman]

hi there

my boiler is firing, burning and works but as soon as it starts up it heats up too high and cuts out above 88 degrees.

the pump does not sound like it's turning, it vibrates and gets hot but the pipes above and below are not hot.

does it sound like it's knackered ?

can I test it by removing the 4 allen bolts ?

cheers

 

[Hugh Jaleak]

See http://www.diynot.com/forums/plumbing/boiler-central-heating-faqs.175736/ No. 14

 

[reapairman]

thanks for that, I read it before but it didn't make sense the first time.

My pump doesn't have a manual switch on it, for modes 1-2 but I could tweak the service settings via the panel to test it. not sure if that worked but basically forcing the shaft to turn with needle nose pliers fixed it.

hot and happy now