Adding an extra pump to heating system

[Carnegie]

I have a relatively new central heating system which has 25 radiators including 4 towel rails. The Valliant boiler, sized to provide the appropriate BTU, has an inbuilt pump but circulation to some of the downstairs radiators appears restricted and maybe the pump is having difficulty getting the full circulation. I also have a Santon unvented cylinder for hot water.

Is it possible to fit an extra pump to the heating pipework to give the system a boost.

The heating pipework from the boiler travels a long way and up and down, to get to and return from all the rads

 

[dontknowitall]

Not sure if it's possible but I'd have thought that changing the pump for a more powerful one would be the way to go.

 

[m4rkeb]

sounds like you need to balance the system and range rate the boiler to stop it ramping up. shouldnt need another pump

 

[diamondgas]

:iagree: ballancing correctly the hot water circuit and heating system should overcome the problem, if the pipe size supplying all the rads is correct!

 

[stevetheplumber]

correct way would be a low loss header and larger pump or possibly two running from that but if pipework is under sized you may have to rerun some of it
25 rads is going to be well over 100 000 btus of load so pipework needs to be 35mm minimum at the start

 

[SimonG]

I would have gone into multiple zones with valve and pump for each (2 htg and 1 hot water). Wouldn't have thought about the header though, might have to look at them for bigger installs.

 

[stevetheplumber]

I would have gone into multiple zones with valve and pump for each (2 htg and 1 hot water). Wouldn't have thought about the header though, might have to look at them for bigger installs.

i was thinking of how to add a pump i doubt if theres a upgrade for what sounds like a system boiler
but doubt if id have used a system boiler for that many rads, preasure vessel is probaly under sized as well
its obviously a large house with 4 bathrooms and 21 rads

 

[diamondgas]

Good shout steve, regards low loss header. :clap:

 

[vectra65]

had this before on a job combi system just added extra expansion vassel to system did job ok

 

[diamondgas]

Vaillant do a 46kw system boiler with low loss I believe steve ... not that I've ever fitted one mind! oooooh! me back!!! Thinking about it brought on a twinge!! :rofl: