3 radiators nor heating up much?

[vass]

Hi guys,

Im hoping someone can shed some light on my heating issue. I am a total novice but researched as much as i can and tried a few things to no avail. Apologies if this goes on a little but i want to give as much info as possible!

I am in a house with a combi boiler. We moved in 2 years ago and had to get a power flush due to sludge. Things seemed to be ok after that but this winter it appears the the radiators in the livingroom, porch and downstairs toilet get only like warm. The heat seems to be more towards the extreme top and sides of the rads.

I suspected this may be sludge again but after reading about balancing the system (as these rads seem to furthest from the boiler i think) I tried that. It didnt work and i ended up closing off all other rads completely to try and get as much floe to the downstairs as possible but the heat they reached was just the same as before.

I thought it may be the pump that was the problem but the inlet pipe to the 3 rads were very hot, just not the rad.

So today i drained the porch rad and connected a hose to it and flushed it out. There wasnt sludge in it as such but there was a lot of black particles in the water. Whatever that was it was heavier that water and separated from it.

The rad is now back on and filled up. The system is pressurised again and now for some reason the inlet and rad is stone cold? Not sure how i managed that but seems to be a step backward. The lock shields etc are open.

There is a few very slow leaks with some green liquid gathering on the floor.

I do need to increase the pressure in the system monthly. There seems to be a bigger difference in pressure than there used to be between the heating being off and on. If the pressure is above 2 bar when off it is likely to shoot into the red when the heating is switched on.

I appreciate this is a lot of information to digest but if anyone has any suggestions i would be grateful to hear them!!

Thanks for your time!!

 

[PrenticeBoyofDerry]

If you are constantly refilling system without introducing an inhibitor, then you are constantly introducing oxidised water which will corrode the system.
You problem is likely to be sludge again. What size pipework is it? You may have now blocked it when draining down!
You need to address any leaks, then fill. up, bleed, flush out, fill up introducing a chemical cleaner, bleed, run for a few days, then drain back down, fill again and introduce an inhibitor and bleed.

 

[GodKnows]

Hi all,

You have way too much pressure in the system, it will expand and cause the prv to open and vent the water! I would check or change your rad valves, as you state that the pipes leading up to the rads are hot. And you have opened the lock-shield valves, but, the system needs to be "balanced" properly by a suitably qualified engineer, you need 12 degrees difference on them. By, the way, water company's don't supply "oxidised" water, that is water that contain excessive micro-organisms. It's the oxygen in the water that causes a chemical reaction in the radiator and produces magnecite (Black sludge).

Suggest you find a local heating engineer who would remedy and balance your system