Central heating chaos

[CMJB]

So where to start
I moved into a property that had single pane radiators earlier this September. We had some work done on the house and whilst the water was off we had the downstairs radiators upgraded to more efficient radiators. The upstairs remain the same on 15mm pipes and downstairs microbore 8mm. The radiators downstairs will not stay warm or even go warm each time the heating is on. This tends to need manual balancing and results in still some not working. Mostly downstairs do not work.
I have had two specialists come out with the following being done
Flushing
Balancing
New pump
New pipe work around the pump
Valves checked on radiators

Still not working correctly all the way around. Parted with a lot of money during this whole process and now engineer will look to change the diverted valve in the heating cupboard incase this is the issue.

If not then we are talking about repiping the downstairs to larger pipes but of course this may work but run the risk of still being an issue.

Anything anyone has seen before?

It’s a hot water tank set up. No combi

 

[terryplumb]

Are the downstairs new rads conventional panel type or something else ?
If you close the TRV on all upstairs rads ,do downstairs rads now heat fully ? Do this whilst there is no demand for cylinder water to be heated.

 

[CMJB]

Yes they are conventional.
My heating guy turned them all off upstairs and said it’s bizzare none are warming downstairs. Then as he did put the on they started to warm downstairs. Slowly. Some just like warm. Then when heating goes off and back on again it all goes cold downstairs and hot upstairs again.

Does this help?

 

[terryplumb]

Do you have zonal heating ,thermostats for both up and down stairs ?
If not ,there is a circulation problem with downstairs radiator pipework.

 

[CMJB]

No just a thermostat via a hive connection. All the radiators have standard valves. No thermostats.

The option now is this new potential diverted valve which the heating guy said when he fiddles with it it does improve the heating (more radiators on) but not all. Hence he said about new piping.

Anything I could be missing?

 

[CMJB]

Also I just had downstairs working except a few. Turned thermostat down and turned back up again later and back to cold or Luke warm radiators.

 

[terryplumb]

Changing the " diverter" valve ? Is that a mid position valve ( has 3 pipes connected to it )? If so it won't do any harm ,but I doubt it is the root of your problem. It's more likely to be blocked microbore pipework,assuming the radiators downstairs were correctly plumbed in originally .

 

[CMJB]

this is my system

 

[CMJB]

Regarding downstairs ones, the radiators were replaced but no change to piping as the valves on old radiators were left on. The heating guy mentioned microbore issues but can’t see how the pipework has been done as it’s in plasterboard and I have chipboard flooring upstairs so he said it may just be a case of new piping on the problematic radiators from the ones upstairs surface level on the wall to limit major rework on plastering etc.

Just fed up paying all the money. I already had two flushes with chemicals and system has been emptied easily 7 times due to bathroom work being done and the issues faced here.

 

[Stuckinarut]

So, as per your photos you have a 3 port mid position valve. Select heating only and feel the pipe going into the cylinder (the thing with yellow foam on it), if that’s getting warm/hot, then there not enough heat going to the radiators.

 

[CMJB]

So the big yellow thing is like warm to touch. The cupboard lets out some heat…
Also manually playing with valves tonight has helped some radiators as mentioned above but whilst some are mildly warm the others are warm at top but bottom cooler. As mentioned this has been washed and emptied multiple times so shouldn’t be sludge. This is the new ones also. The single pane upstairs are so hot to touch even with a 1/4 turn or less.

Not sure if that gives anymore to this whole thing

 

[Stuckinarut]

Could be the automatic bypass has failed. If it’s been flushed to no avail, then it’s either not been done properly or there’s a flow restriction.

 

[CMJB]

So what he plans to do tomorrow will that help?
Just trying to avoid repiping the downstairs tbh.

 

[Stuckinarut]

So what he plans to do tomorrow will that help?
Just trying to avoid repiping the downstairs tbh.

It may do, but you’ve just said the pipe is only warm, so I wouldn’t be that hopeful.

 

[CMJB]

Yes some are hot to touch to the radiator but the radiator is a mixture of warm and bottom of radiator not so warm. I’ll mention the bypass to him also see what he says. I’m also trying not to have more of a bill on trial and error. So far we have spent £1500 in the last fortnight trying to sort as I have babies in the house. Husband is not a handy man so trying all that I can.