What pump size for 18 rads?

[MrGood]

Hi, my family and I are having a great amount of trouble with our heating system. We have had 2 so call professionals out, 1 fitted a new pump and left us saying it was the pump - no effect, the other charged us £50 for 20 mins work resetting all the rads thermostat levels, but also saying our pump is not powerful enough!!!
We are having trouble with the living room radiator it will not heat up, the inlet pipes arn't even heating up. If possible can anyone let us know what reccomended pump size for around 18 rads is? we at the moment have a (60) if thats any help.

 

[ricarbo]

18 rads implies a not enormous house so a standard sized pump might be fine. If you want to know for sure you need to give a lot more detail, like heating output, number of floors, pipe sizes etc. You could make enquiries of a pump manufacturer such as Grundfoss.
Has the system ever worked properly?
There could be a sludge blockage or airlock problem, rather than a pump problem.

 

[jobloggs]

Can't advise on pump but radiator may have a sticking thermostatic valve. See under sticky references 4th post down on first page.

 

[MrGood]

thanks for speedy reply, relieved to know that pump is big enough, so now i can concentrate on air and sludge. We are finding sludge in a few places including water tank.

The inlet pipe on that radiator (next to the thermostat) that doesnt work is not warm, suggesting the heat isnt reaching that room at all, there could be a possible blockage, however the rad is bled, and water seems to be refilling the radiator if we drain it out.

 

[Softus]

18 rads implies a not enormous house so a standard sized pump might be fine.

How so? 18 rads implies at least 14 rooms - sounds to me like an ENORMOUS house.

If you contact a pump manufacturer, for example Grundfos, they will help you choose a pump. For your system I would expect them to recommend beefier than a 15-50.

 

[MrGood]

thanks for all you help, what solved it in the end basically was,

we put the Cold feed directly into the vent via a 3 way splitter and blocked off the existing cold feed therefore no air can get into the system. Now it heats up fine.

 

[Gasman1015]

I hope you have'nt left your vent blocked off...