hello all, first post so please be gentle .

We,ve had a potterton puma combi boiler for the last 7 years, in general it has been a proper pain in the ass , its gone wrong so often that im almost a fully fledged puma specialist now! with everything from split exhaust sensor pipe to a motherboard that caught fire!!!! (yep as in really caught fire!!!!! grrrrr ). I mean fair dooos to all o that..... BUT!

The thing that really bugs me is the way it somehow manages to seize the CH pump once a year! (we had one good run of 2 years once ) Its almost like clockwork just before chrismas . This poxy puma has gobbled 5 pumps to date and at nearly £100.00 a pop (at the local rip off merchants round my area) they are not cheap to replace.

sorry for going on, the questions are.....

1) Why should the pump seize when the water is clean and the bearings have been vented properly.

2) Is there anything i can put in CH water system that will lubricate the bearings, ie car antifreeze. (that has a lubricating action)?.

The local mojo heating merchant round the corner says there isnt but he also said you cant get cheap heads to replace the CP61 unit, which ive since found not to be true.


cheers in advance
duncan