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boiler or radiator problems
Hello, since about a month, my radiators are not as hot as they used to be, all radiators as hot at top and warm at bottom, which means I do not reach the temperatures set in the room even after many hours of being on. The boiler is Bulex condensation type, called the technician and according to him all was OK with boiler but I have a slight doubt. Having searched internet, I see hot at top and cold at bottom of radiators usually points to sludge, but can all radiators be affected, and if that's the case, it has come about quickly over the past month - strange. Another possibility could be that the pump on the boiler does not function well enough - on the cycle indicator I see that the cycle for pumping heater water (admittedly temp indicator is ca. 65C) lingers for a long time - I don't think it was like this before. Not sure if there is not supposed to be a "pull" cycle associated with the push of water - I do not see this "pull" cycle which I have seen before (maybe only for hot water ?). I also feel that the hot water in taps is not as hot as before, but not sure since I have not measured.
Anyone had such a problem before and suggest what the cause could be ? Also any recommendations for a heating engineer (chauffagist) in the 1200 area of Brussels ?
Thanks in advance.
If you have a condenser boiler, then you have a global thermostat. That should be set at 20 degrees day temp., and 18 degrees night temp. The room with the thermostat should reach 20 degrees. The system works out how hot the water in the radiators needs to be based on the difference between the outside and inside temperatures. They may not feel hot to the touch, but should just heat enough and no more.
Turn up the temperature to 21 and see if it makes a difference.
Check the outside temperature probe is connected properly and is working.
(mind you - quite how you do that yourself, I don't know)
I have a similar problem with hot on top cold on the bottom, but it comes and goes and never figured it out. But my heater is 20 years old. Anyway, the man who services the boiler will be here I hope in a couple of days, and if I learn anything I will post.
I have the same problem from time to time.You need to remove the thermostat knob from each radiator and pull gently on the tiny valve or tap it gently with a hammer until it release. Then the heat will disperse equally through the radiator.I recommend the company Sapart 027319355 who I use for the past several years. They are father and son and are brilliant.
this only applies to certain kinds of radiators, but if there is air in the radiators, they don't work properly. mine are quite old, and this can happen too them. there is a little key that will release any air. when water starts coming out, all the air is gone.
'air pocket would result in the opposite phenomenon - cold at top, hot at bottom.'
Logically so - but logic doesn't always apply. When I checked my radiators at the start of this 'central heating season' I found one which was cold at one end and hot at the other. I admit that I have never encountered such a phenomenon before but bleeding it solved the problem.
If ever I found a radiator that was not evenly heated, I would bleed it if only to satisfy myself that air in the system was not the problem. You could also check that there is enough water in the system. My, Bulex, system has a gauge on the water supply though I have no idea whether that is an absolutely standard set-up.
It's to do with how the system s balanced you have to turn off all the water then turn back just enough. Never done it but you get info on you tube etc. if it's too complex get a good heating engineer,in to service and ask them to balance. Also here calc deposits can cause issue.
Also double check the thermostat values aren't stuck
