rads hot upstairs,but cold downstairs

[sparkyjim]

ok,this is a longish tale.I only have 2 downstairs rads at the moment,but over the past 2 weeks they have got colder and colder.Upstairs are fine and hot water fine.So i changed my pump,just to eliminate it from the problem.Pump and hot water fine ,but now no rads working.Started to rip house and floorboards apart.Found a 2 port solenoid?or valve? under floorboards in upstairs landing.Now the feed pipe into the valve according to the arrow on it was cold,but the exit pipe was hot.I had the mrs turn my boiler power switch on and off,and i got 240 volt on and off onto this valve.It had alarge knurled nut holding it onto the body of the valve,so i then undid this and lifted it off.I pressed the plunger that was sticking up from the body on the pipework,and after a few minutes hot rads all over.I then cable tied this into position.Now my problem is this,the unit i removed has a spindle assembly which must have pushed down on the other spindle,if i put power to this unit should it move?Also if i switch my rads off at thermostat in the hall,they still stay hot.I might add that this unit only had a 240 v feed to it,no return wiring.Any ideas?

 

[oilman]

I tell you what, you tell us the manufacturer and type of valve and pump you have, and we'll try and help.

 

[galwag]

I vaguely recollect this valve
I believe it was manufactered by a company called Smiths
It is at least 30yrs old and is obsolete
Change it for a Honeywell

 

[sparkyjim]

thanks for the replies.i have checked my controller and it is labelledup as a centroller4O manufactured by smiths.The valve has no makers name,but it too is labelled as centroller,made in west germany.Will i have to change both units,or can i get away with fitting a two port honeywell.Any ideas what make of honeywell i can get,so i dont stand there like a twit,and take the first valve im given