Baxi Combi 80Eco - Inconsistent heating

[stupot1975]

Hi all, Merry Christmas.

Been having a few problems over the last few months and have had several engineer visits, all related to heating.

Heating was not working at all when we called an engineer, but to cut a long story short he just succeeded in breaking the filling loop - meant we had pump and prv working constantly until I could get another guy out (over 1 day). They repaired the filling loop, reset the system and it was just started working fine again. Everything was running well and rads were warm all round the house.

In the last week or so though the upstairs rads are getting warm, as before, but the the downstairs ones are barely heating up. I rebalanced the system which worked for a while, but today the downstairs ones were cold again. I closed the upstairs rads to try to force air / whatever downstairs and whilst they are warm the system is struggling to maintain 19 degrees.

Wondering whether the broken filling loop has caused some rubbish to get into the system, or replacing it has caused large air pockets to get in? Or perhaps the pump has become weak?

As a guy who knows little about this I'd appreciate some advise before I call somebody else out again in the New Year.

 

[Agile]

Its difficult to imagine how you can call someone who is unable to even repair the filling loop!

Its a little difficult to guess exactly what your problem is without further information like flow and return temperatures.

It could be pump problems, balancing, sludge, airlocks etc. But as always a competent heating engineer should be able to diagnose the problem and fix it!

Tony

 

[bengasman]

Corrosion and sludge is my first thought for downstairs cold rads.
Pump is next suspect.
Possibly sticky diverter blocking flow.

 

[stupot1975]

Thanks guys. Agree from searches I made before I posted that it sounds like sludge / corrosion, however...

Neglected to mention before that my uncle (fully qualified, but now working away) had fitted some new rads within the last couple of years, flushing through first and putting more than adequate inhibitor etc. in, so it shouldn't have gone 'off' so quickly, should it?

Since I posted I have done some more 'testing' and turning upstairs rads off makes downstairs warm; turning upstairs on makes downstairs cold. Therefore it seems all rads do get heat through, although inconsistent, and less than a month ago all was working ok.