New boiler constantly need balancing?

[gerbils]

New boiler conversion (gravity to combi). Plumber left us with inconsistent rads, 24 hours later all 13 refuse to heat up above 30 degrees.

No issues with thermostat, and boiler is turning on/off as needed with that.

I took advice from an old post on here and shut off all the radiators and opened one up which got very hot, I then opened all the others simply by turning each rad valve 1/2 turn until it was hot then moved on to the next (bleeding along the way where needed). This worked fine for 1 day but the same issue occurred the next, all refusing to heat up. Another balance was done, this time opening each one up a little more than the previous one, and again fine for 1 day but now cold again and the boiler appears to constantly turning on/off every 10 mins trying to heat them up.

Installer seems to think this sounds like a blockage and has offered to reflush the system; but if that was true why would it heat up when I close them all down and re-open? Just trying to understand our options.

He can't come back until next Friday so is there anything else I can try in the meantime so we have a warm home?

DHW is fine.

 

[JohnD]

You fine-tune the balancing by slightly closing the hot ones, not by opening the cold ones

Please describe how your old gravity system was flushed. How long did it take?

What sort of filter have you got?

 

[gerbils]

You fine-tune the balancing by slightly closing the hot ones, not by opening the cold ones

Please describe how your old gravity system was flushed. How long did it take?

What sort of filter have you got?

Problem is they are all cold so I can't fine tune.

We had a MagnaCleanse system flush but I am a little cynical about how long they ran it based on noise etc. It felt like about 30 mins and I expected it to be a couple of hours - for starters they were huffing and puffing about doing it and how it would mean the job went over to 2 days (they did it in 1 in the end despite this).

We have a Magnaclean Micro2 filter attached.

 

[JohnD]

Is there much mud in the filter now?

Combi, so no hot-water cylinder?

 

[gerbils]

FYI I have also tried to do the

Is there much mud in the filter now?

Have you got a hot-water cylinder? Is it surprisingly hot?

I haven't looked. I will google over the weekend how to check the filter.

We had our cylinder removed, just a combi now.

 

[gerbils]

FYI I have also tried to work out which radiator heats up first but even when they do heat it it's generally about an hour for them to do so.