How long to heat house.

[clayton]

You are seriously loosing a lot of heat somewhere. Is it double glazed, are the outer doors modern sealing ones, has it cavity wall insulation, is it a dormer style???

For comparison - I have all of the above, but standard 3 bed semi rather than dormer style. Heater went from 20.5C at 11pm last night, to its set back of 16C for the night. The boiler never fired all night, but the temperature was still 18.5C when we got up at 9am and turned the stat back to 20.5C - which it had satisfied by 9:30am. Outdoors was sub- zero much of the night.

Two of the bedrooms are dorma style buy they are warm its the ground floor I have an issue with.re cavity wall insulation its something I've been looking into but seen bad reviews about damp after having it installed.

 

[clayton]

This is a guess, I will guess the lock shield valves are not set correctly and as a result the the boiler is modulating. The modern gas boiler has a variable output. It seems reading the manual your boiler has an output 10 kW to 30 kW, to get the 30 kW the return water must be cool.

I am electrician so not sure on valves, but I thing around 15°C temperature drop across the radiators, unless set you get room by room heating, so easiest room to heat the radiator gets hot, and then the TRV starts to close, as it closes it heats next radiator, and so on.

The mistake every one makes is to look at the cold radiators, where the error is more likely to be with the hot radiators. So most likely you need to turn down the lock shield valves on the hot radiators.

I now have a thermometer I could use, just aim it at in and out pipes, but before I had that tool I would turn off the Lock Shield closest to boiler, then 1/4 turn at a time back on until one pipe gets just warm, and then repeat with rest, once all done they may need further tweaking, but it should be a good start.

The other method if not due to poor lock shield settings is to use programmable TRV heads and actually design the system to heat room by room, but I suspect the lock shield valve setting is the fault.

I have balanced the radiators and might check it again but I think the issue is the hall radaitor being under sized, my only concern is fitting a larger rad might make the rest of the house colder.

 

[Harry Bloomfield]

Two of the bedrooms are dorma style buy they are warm its the ground floor I have an issue with.re cavity wall insulation its something I've been looking into but seen bad reviews about damp after having it installed.

It seems to be a case of the CWI installers, installing it where it is not appropriate, or using the wrong material for the circumstances, rather than being a basic problem of CWI. No problems here and the place is noticeable warmer, with lower bills. Always remember - be generally only complain when something goes wrong, they are quiet when it goes right.

 

[CBW]

How big is the hallway and how big I see the rad?

 

[clayton]

How big is the hallway and how big I see the rad?

The hall is L shaped 3.175 x 2.604 x 2.420h radiator is 600 x 1000 single convector.

 

[Terrywookfit]

Older systems were designed for a hallway and bedroom temps of 60 F. Bathroom and Kitchen 65 F. and Lounge Diner 70 F.
If correctly sized AND doors were closed These temperatures would be maintained.
A gas rate of the boiler to determine how much heat is being put into the rads would be helpful. Compare this with the rads output to see if enough heat is being generated.

 

[CBW]

So being quite open by the stairs, a lot of heat will be lost going upstairs.

 

[ericmark]

I have balanced the radiators and might check it again but I think the issue is the hall radaitor being under sized, my only concern is fitting a larger rad might make the rest of the house colder.

I had same problem with mothers house, large hall radiator there to reheat hall when front door opened, but otherwise heated hall too fast, cure was a TRV on hall radiator set to 3.25 on a *123456 wax head and wall thermometer set to 19°C used the stop inside the thermostat so when turning heating down, and back up again, always stopped at same point.

Theory which seemed to work in practice, door opened so hall at say 12°C takes some time with late Mother in wheel chair, the heating goes on and the TRV is wide open so only the lock shield valve controls flow in radiator, at around 17.5°C the TRV starts to close, but it is not fully closed until around 20°C so before 19°C the radiator has started to cool so on a cold day the wall thermostat was never activated, but on warmer days it did work.

I repeated the idea with this house, however not been quite so successful, mothers house one door between radiator and wall thermostat and curtain across stairs to stop too much heat going up the stairs, this house two doors between radiator and thermostat, and no stair curtain, found wall thermostat in winter records about 3°C higher than TRV, but in summer shows the same, so the difference between the two thermostats has to be tweaked as we go from Autumn into Winter, and again as we go Winter to Spring in my house, but did not need to do that with mothers old house.

The other big difference was mothers boiler modulated, so Autumn and Spring radiators only warm, only in Winter were radiators hot, this house has oil fired boiler that only switches on/off.

So it does depend on boiler used and house design, there is no one method fits all, but the idea was the wall thermostat for a modulating boiler should be fitted on ground floor, in a room normally kept cool, with not alternative heating, and no outside doors, the problem is that room rarely exists, we don't want it in a room kept warm, or as summer arrives the boiler will pre-heat house before the sun raises then the sun will bake the house, so really wanted in a room kept at 19°C or less, one method tried in mothers house before fitting the TRV in hall was two thermostats in parallel one in hall and one in kitchen, with limited success, but fitting the TRV in the hall was turning point at getting control over central heating.

 

[lostinthelight]

How is your house getting down to 14c?

Easy and lower when living in a 17th century one

 

[HERTS P&D]

Easy and lower when living in a 17th century one
View attachment 216902

Jesus wept, chuck another log in the burner!

Andy

 

[Old Salt]

Your hallway radiator is not connected and has fallen off the wall

 

[lostinthelight]

Jesus wept, chuck another log in the burner!

Andy

WHAT! and waste the money I spent on a new fleece

 

[gasbanni]

Turn the boiler stat to max

Don't forget heat rises so the hall may feel colder, shut the upstairs doors, does the landing get warm from the hall rad ?

Put the nest well, away from a rad !!

 

[clayton]

Update.

The boiler still seems to cut out even when the nest is calling for heat, you just notice every now and then that the room had got colder.

I think the issue it to do with some sort of blockage in the pipes, some of the 15mm and 22mm pipes close to the pump attract a magnet when placed close to the pipwork.

I've drained the system down and added some system cleaner and left it for a week, then refilled again with more cleaner so will leave it a further week before flushing the system again.

One thing I did notice today while up in the loft at the F&E tank is when you turn the hot water off via the nest app a shot of water enters the tank, this again is possibly due to some sort of blockage, correct me if im wrong.

Options do I cut out and replace the pipework the magnet shows could blocked or pay out for a chemical system flush ?

 

[Nige F]

You're right about a partial blockage - can you post a photo of the area where the magnet sticks ?