Plumbing Question

New boiler fitted - some rads (previously working) now not working

My 5 year old boiler stopped working recently (it had been serviced 3 weeks earlier). I called the guy who did the service out and he told me that I needed a new boiler.

***** UPDATE ********The old boiler was a warmflow 90. The new boiler is a Grant Vortex 90/120 *********

New boiler was installed yesterday and now 4/16 radiators not working. Two of the stone cold rads are upstairs, two are downstairs (a further two downstairs are lukewarm)

The Boiler guys reckons its just sludge in the system (it wasn't affecting the rads before he installed the (condensing) boiler and he thinks flushing out the rads will work. I can't understand why it could be the rads if;

1) they were working beforehand
2) the pipe going into the (cold) rads is also cold

Thoughts/ideas would be really appreciated.

4 Answers

Best Answer

update - Hmmmm , do you have microbore pipe ( 8mm diameter.

You need to state what boiler you had before, and what you have now. The new boilers hate sludge, and as per manufacturers installation instruction the system has to be flushed in accordance with british standards to make their warrantee valid. And have a magnetic vessel fitted as well to keep it clean.

Answered 9th Dec 2012

pjb plumbing & heating

Member since 17 Apr 2012

sounds to nme that theres still air flowing in system. i had problem at my personal house. i took out the blead valve and put a big bucket at side of radiator letting the water fire in and eventually it shot air bursts out i duid it to every radiator. after 30 mins of doing this all radiators were boiling :-) worth a try first

Answered 2nd Jan 2013

a1 plastering & tiling

Member since 10 Oct 2011

I'm not a boiler fitter but i'm sure when you fit a new boiler the system needs to be cleaned before, otherwise it invalidates the boiler guarantee. Check the manufacturers instructions.

Answered 9th Dec 2012

Park Plumbing & Tiling

Member since 16 Nov 2010

It would be impossible to give you a correct answer from the details you've provided in your question, but I'm almost certain sludge is not your problem, partically because there's 2 upstairs rads not heating. Sounds like an air lock, system needs to be re-balanced. I'm guessing you've got an open vented oil fired system, and it just needs a bit of re-adjusting, venting all the air out. Which can be a mission sometimes.

Answered 29th Apr 2017

CD Plumbing and Heating

Member since 21 Apr 2017

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