CH issue - advice needed

[noidea1]

Hello

My daughter lives in a small terraced house, 2up 2down scenario, in the last week she had issues with the CH in that rads upstairs were hot but cold downstairs

The combi is a Heatline Capriz plus 26a, 4 years old and the house has 6 rads in it, ive read around and aside from the usual "the boiler is crap" posts found a few possible solutions

Today i went down and bled all the rads but no sign of air anywhere, i then turned them all off and "tested " them one by one, im not exactly sure of how the system flows but tried to follow it logically.

The boiler is in the kitchen downstairs and first rad is the bathroom followed by back bed then front bed, down to hall , into living room and finally back room.

each radiator i tested in isolation heated up ok but once all were open again the downstairs cooled and failed to heat

We will get a plumber out this week, same one who fitted it but was just wondering if anyone had any ideas on what the issue could be ?

Hot water is fine both to the kitchen where the boiler is situated and the upstairs bath room

Cheers

 

[Mottie]

Balancing?

 

[DP]

With all rads on line, any radiator heating adequately?
Is the initial hot water flow at tap red hot?

 

[ianmcd]

The system needs balancing

 

[noidea1]

With all rads on line, any radiator heating adequately?
Is the initial hot water flow at tap red hot?

Hello

Thanks to all for the replies

The upstairs rooms were heating up ok with all rads on but were cooler along the line , downstairs were stone cold. TBH i didnt leave the boiler on too long to judge how hot the upstairs got as i didnt want to overstress the boiler if it had an issue but the downstairs did not show any sign whatsoever of getting warm

The hot water is fine both in the kitchen were the boiler is and the bathroom upstairs

If as has been suggested the system may need balancing im just curious as to how it may got "out of balance"

Thanks

 

[ianmcd]

If as has been suggested the system may need balancing im just curious as to how it may got "out of balance"

Probably was never balanced in the first place, you would be surprised about how many Domestic systems have never been balanced, and how many have been unbalanced by users messing around with lockshield valves

 

[noidea1]

Think you may have hit on something there, i dont believe the system was balanced when the boiler was fitted as i was there at the time and her boyfriend has recently moved in with her.....its amazing just how many things have gone wrong since then !!!
I will try balancing myself based on the way i believe the system flows, cant be any worse than now
she will need a plumber for a service anyway soon so he can double check

thanks for all the replies and help

 

[ianmcd]

When balancing , just think, water is the same as everyone, it will take the easiest way possible, or the path of least resistance, so it will happily run full pelt through a tiny radiator rather that push through a large double radiator, so you have to restrict the closest rads and the smallest rads to force the water through the larger and further away ones , you do this by reducing the lockshield valves and forcing the water flow to the harder to reach rads , to do it properly takes a bit of patience, there are many opinions about what is the best way, I personally can do it by hand and feeling the Flow and return pipes but I am an old geezer and have been doing this for a very long time, have read the posts about laser thermometers and digital delta T thermometers, we all have our own preferences

 

[DP]

6 radiators should not result in stone cold radiators downstairs.
When I asked you the question about hot water temperature initial stream from hot tap, what I am getting at is, your boiler ( if a combi boiler) at its minimum will be 24 kw. Guesstimate of heat required based on 1.5 kw per rad, you only need about 9kw total. When ch is run, internal circulation through the plate he would spike initial hot water flow

My guess is you have internal circulation in the boiler ( bypass passing or diverter not shutting hw port) Again not knowing what make and model of boiler you have, I am assuming a lot but what you have issue with, I have sorted a few times as rads close to the boiler heat up but as the distance from boiler increases, poorer the output from further away rads


Not saying system does not need balancing, only that what you have could be other causes too. Get a heating engineer in to look at the system ( not a plumber who does not know how the system or boiler works).