Central heating possessed....toddler room 12C our room hotter than the sun

[cakebaby]

Can anyone help? New build (12 mths old) gas central heating, 2 thermostat, for upstairs/downstairs. Some radiators are adjustable, others aren't. Upstairs thermostat set to 20C overnight. Master bedroom is boiling, ensuite unbearable so we've turned rads down low. Hall lovely & cosy, toddlers room 19C at 7pm, this morning was cold at 12C, other rooms rads were on & cosy, toddlers rad was stone cold. Rads have been bled, boiler pressure is spot on. We had the heating engineers back twice last winter but nothing improved. It's going to be the same this winter too if we can't figure this out.

WHY is the room so cold? Why does the radiator not come on when it's bloody cold? In our last home we had a combi oil boiler, when the thermostat was at 20C each room was the same temp. Why is this new heating system not heating each room the same?

We're back to putting the oil filled radiator back on overnight in toddlers room

[PigletJohn]

All radiators are adjustable.

What kind of thermostat have you got, and which room is it in?

[BrokenFoot]

I'm no expert so feel free to ignore my ramblings!

To me, 20 degrees seems quite a high temp to have set for during the night. I would probably drop it to 16 or 18 depending on how warm you like it. Where is your thermostat? If it is in your room for example and your room has hit 20 degrees, the thermostat will turn the heating off regardless of how warm other rooms are.

You need to have the thermostat somewhere that is not the hottest or coldest place in the house. They often recommend the hall I think if it is not too cold.

If it is in your room and can't be moved could you turn the radiator down quite low in your room to keep the temp down so the heating stays on and thermostat doesn't turn the boiler off?

[cakebaby]

Hi pigletjohn it's a digital Dreyfuss or something. Upstairs Thermostat in master bedroom on Plaster board wall adjacent to airing cupboard. That wall is always disproportionately warm as massive heat source behind it downstairs thermostat in hallway.

Have tried it on daily/weekly timer and just leaving it on at varying temps but toddler radiator does its own thing.

[PigletJohn]

Danfoss

If the thermostat is in the same room that gets warmest, you must turn down the radiator in that room so it warms up slowest. Don't use a TRV (it should not have one in that room anyway).

Take the plastic or metal cap off the lockshield valve. Screw it down fully shut. Then open it half a turn and wait half an hour. Is the radiator now warm all over? If not, unscrew the lockshield a quarter turn and wait another half hour. lockshields should be almost closed, otherwise they may as well be fully open.

One of the radiator pipes (the return) should be detectably cooler than the other (the flow).

In order to balance radiators, they should all be somewhat turned down with the lockshield, otherwise all the heat will go through the closest radiator, and the others will receive less, or perhaps none. On every radiator you should be able to feel the difference in flow and return temp. Nominally 12-20C is the correct drop, but if you can get the flow "too hot to hold" and the return "too hot to hold for long" on all the radiators, that will be near enough. If any rooms are still too hot, turn them down a bit more. The lockshield valves should have the knobs taken off and a cover fitted to prevent anyone fiddling with them and losing the adjustment setting.

Remember that when you have some hot radiators, and some cool ones, you fix it by turning the hot ones down.

[cakebaby]

broken yes it's far too hot for us but it was an attempt to keep toddler room from freezing over!

pigletjohn thank you! DH is going to try your suggestion tomorrow.

The heating engineers who came to try and solve the problem TWICE last winter told us the radiators without TRV's could not be adjusted!

AIBU to expect that these same engineers, who are from the large company that installed the central heating, should probably have tried this last year?!

Mind you they also wired the downstairs system to the upstairs thermostat and vice versa.

And did the same to next door

And forgot to connect the main waste pipe to the mains sewers (we discovered it 3 months later boak )

[PigletJohn]

Balancing the radiators should have been done as part of the installation.

It might not be quite right first time, but you will know if they had a go when you screw down the lockshields. If they are all more than a couple of turns open it was not attempted.

www.mumsnet.com/Talk/property/a2205419-New-radiators-not-getting-hot#50023831

[RandomMess]

Any chance it would work if you just turned the radiator in your bedroom completely off?

I turn the rads off in my dds room and then just tweaked so a tiny amount of hot water went through them so they weren't freezing to touch. We had a generally very warm house.

[AIN]

Did you self build or buy? If you have brought your house new then you should still be on the 2 year period where they fix everything for free.

[cakebaby]

random yes we tried that but no difference!

AIN we bought new & engineers came twice last year to fix but it had no effect.

pigletjohn I think you have it! DH got to work today & our radiator is warm, toddlers is lovely & toasty! All the radiator valves were open to differing degrees. We'll probably adjust again tomorrow to fine tune.

Thank you so much