Combi Central Heating

[ala.nicholsaon]

In a very small flat I am connecting 4 rads to a 24KW combi. The Flow & return on the boiler are standard 22mm. Because of space constraints I will not be able to use manifolds and I propose to reduce the 22mm to 15 mm and pipe all four rads in parallel using 15mm throughout. Is this likely to cause any problems?

Regards
Alan

 

[Barry98]

not if its done right no

 

[tipintim]

I dont think youll have a problem at all. Worst senario is balancing the locksheilds.
It will be fine! :26:

 

[Nat]

I'd keep it in 22 until the first tee, 22-15-15.

 

[stevetheplumber]

im with nat 22 to the first rad

 

[shorticus]

you don't say which combi you're using, if the pump has a speed switch flick it to the lowest setting, otherwise there shouldn't be any issues

 

[SimonJohns]

you don't say which combi you're using, if the pump has a speed switch flick it to the lowest setting, otherwise there shouldn't be any issues

You can't do that you fool

It need to be on 3 to give the hot water output

 

[shorticus]

You can't do that you fool

It need to be on 3 to give the hot water output

I beg your pardon, who are you calling a fool!?

 

[Halesowen1]

It will be fine to do that, but beware if you ever want to add extra rads or start fitting bigger ones you may get problems and have to re-pipe.

 

[marleyco]

Others may disagree but I might run 10mm to radiator's from a 15mm flow and return, this might avoid the problem of balancing the system as much or at all.

 

[SimonJohns]

I beg your pardon, who are you calling a fool!?

You!

Why or when would you ever turn the pump speed down on a combi

Please elaborate as to when a manufacturer has reccomened this or when in your professional opinion have you done this and supported the hypothesis with strong technical knowledge

 

[shorticus]

Others may disagree but I might run 10mm to radiator's from a 15mm flow and return, this might avoid the problem of balancing the system as much or at all.

...it'll only be an issue for those who don't understand how a centifugal circulator works or who can't read a pump curve!
Personaly I've never been a fan of microbore due to the imminent sludge issues, having said that if a decent inhibitor is used and the levels are checked annually then why not!

 

[ala.nicholsaon]

Thank you all for your input
Alan

 

[shorticus]

You!

Why or when would you ever turn the pump speed down on a combi

Please elaborate as to when a manufacturer has reccomened this or when in your professional opinion have you done this and supported the hypothesis with strong technical knowledge

Whilst I'm more than happy to enter into any kind of technical discourse I take particular exception to anyone throwing insults at anyone on this forum, it's not what its about. If you have a differing opinion to mine that's absolutely fine, if you would like to explore our differing opions as an adult then that's fine too, now you've taken the time to have a look at my profile you should now be more than aware that you are not talking to a fool.