boiler and heating woes

[snoop]

hi guys

a little help please if you can

a few months ago the central heating stopped working, i had several plumbers out and they could find no problem, one honest plumber told me to replace the pump,then the 3way valve as they were the steps he would have done and as i seemed to have me head screwed on.

anyway,changed the pump and hey presto, we had heating again,red hot upstairs but only warm down.

now its packed in again.

if i turn the thermostat down to 0 on the water tank,the radiators get hot,as soon as i turn the thermostat back to 50 the radiators go cold.

could the 3 way valve be the problem?

any advice would apprecaite

 

[newbie1]

maybe ,,how old is the system the sludge could have knackered the old pump and has now screwed up the new pump

 

[Mike Jackson]

Check the model of the valve. It may be a diverter valve rather than a mid position valve. These prioritise hot water so you could have a fault elsewhere.

Mike