central heating system

[gazbang]

hi, is there anyone out there that can help me??
my central heating system has packed up, it is a conventional system that is atleast 10yrs old that i know of.
I have hot water no problem, but all the radiators went off downstairs one day but were hot upstairs?. I messed about with it for a while and realised if i turned all the radiators off upstairs i got heating downstairs. this is how it has been for a couple of weeks but i really need to do something about it now!
All the radiators are bled ok and the pump sounds and feels like it is kicking in but i still cant help thinking its the pump thats causing it. The pump is a MYSON compact cp53.
has anyone got any advice on what else it could be before i order a pump?? many thanks[/quote][/b]

 

[MANDATE]

well water is lazy and will always take the easiest route available.
If you have a by pass valve that is open too much, it will take that route.
Balancing of the radiators is important.
However the problem could be a restriction around the pump inlet and outlet. Saw one recently where the orifaces were down to 4mm diam.
and that was on a myson compact. Shouldn't take long to remove pump for examination and cleaning.Make sure you have some replacement pump washers.
You may have some problem closing the isolating valves if they are 'gate' valves, you may have to close-open-close-open-close etc. You could buy 2 new valves from B & Q (cause they don't clean easy) and if you don't use them ' return for refund.