adding a room thermostat to my heating system

vaio

EliteHeat wrote: »

The boiler 'sees' nothing and if a combi or a system boiler it will have an internal bypass. The part I specifically did not mention was that if all rads are shut and there is no bypass at the end of the circuit, then there can be no circulation at all (depending on how the system was piped up) - except via the internal bypass. This is probably at a level beyond the scope of this thread though

I meant see as in the boiler flow switch seeing flow. The boilers I used were Valiant and Vockera (sp?) back in the early 80s and on those the by-pass had to be external.

If modern boilers have internal by-pass it only seems a matter of time before they can program them to only fire if there is some external flow from an open TRV. I suppose they could even turn the pump down when there is no external flow thus saving a few more watts.

Having said that it seems to me that any pumping energy used within the boiler isn’t actually wasted as it will make the room slightly warmer.

As you can probably tell, I don’t do boilers anymore but I struggle to see the advantage of the required room stat when flow sensing and TRVs could ensure the boiler only fires when there is a heat demand. Throw in a couple of timed zone valves and you can have bedrooms only on at night and living areas only on during the day which seems a much better system than the somewhat crude room stat enabling & disabling the boiler that’s recommended now.

amcluesent

I added a wireless room-stat to the combi boiler control at my parents house. Made a huge difference to comfort and ease of use, no more fiddling with the timer settings.

want2bmortgage3

my friends dad is an electrician and was here yesterday i asked him about it and he said i could just add a thermostat and connect it to the existing timer/programmer and put it the other side of the wall in the lounge.

would one of these do the job? i notice one says combi stat?
http://www.screwfix.com/prods/85263/Plumbing/Central-Heating-Controls/Drayton-RTS1-Room-Thermostat
http://www.screwfix.com/prods/46637/Plumbing/Central-Heating-Controls/Drayton-RTS8-Room-Thermostat

cheers

smcaul

Get a digital wireless stat, they are excellent. Makes it easy to set a nice warm temp for the morning and then reducing later in the day when you don't really want things as warm. I fitted one last year and the house has a much more even temperature throughout the day.

david29dpo

http://www.screwfix.com/prods/93829/Plumbing/Central-Heating-Controls/Horstmann-HRFS1-Room-Thermostat
This one is excellent.

latecomer

@EliteHeat - thanks for the clarification.

david29dpo

Depends how competent you are. Can you wire a plug? if so should be no problem.

skintandsad

Ooh what a very interesting thread!
I don't have a combi boiler, and my gas bills are astronomic. My understanding of heating systems is non existent I'm afraid

Each of my radiators has one of them caps on it you turn to turn the radiator up and down through 0-9.

Would I be able to make use of a room thermostat? If so, can someone offer advice on which type to use.

My boiler is in the utility, and the controls for it upstairs in the airing cupboard by the water tank. My boiler has a knob on it to turn the temperature up and down, and this is set to midway (not sure what that does???)

Thanks for reading - hope you don't mind me stepping in on this thread xxx

jennifernil

Interesting reading! We are considering whether to fit wireless stats too.

We have 2 fully pumped systems both with their own boiler etc and separate timing of heating and hot water as part of the upstairs is a "self contained" granny flat. There are thermostats on the HW cylinders, and TRVs on all but one small radiator in our downstairs hallway, and one small radiator in the flat hallway.

The downstairs hall is large and + shaped, there are 3 other radiators in the hall with TRVs.

It is a large house (280 sq m in total) with the main living rooms on the upper floor and most bedrooms downstairs. There are 5 radiators upstairs and 13 downstairs in the main house, of which a total of 15 are in regular use.

The flat has only 5 radiators, of which 3 are in regular use.

OH is competent to fit the stats, but I have a few questions that I want to get straight in my mind before we discuss it.........

1. If we get programmable stats, do these override the present timers? (As in running the heating even if the timer says "OFF" , e.g. during the night) Or do we need to dispense with the old timers? If the old timers have to go, then what about the Hot Water?

2. Would it be better to have simpler stats and retain the existing timers?

3. Where should we position the new stats?

katrin_2

EliteHeat wrote: »

The boiler 'sees' nothing and if a combi or a system boiler it will have an internal bypass. The part I specifically did not mention was that if all rads are shut and there is no bypass at the end of the circuit, then there can be no circulation at all (depending on how the system was piped up) - except via the internal bypass. This is probably at a level beyond the scope of this thread though

hallo you seem to be able to explainthings well -
I have normal boiler-the room thermostat is in kitchen cupboard(Dont ask!) I have rad valves. the original plumber said keep the room stat high (or shoudl i call it a cupboard stat) or the rad valves wont work? is this correct. I dont want to be moving thermostat at the moment. boiler seems to fire up alot. shpuld i keep the rad stats to the same setting all the time? Its a big house with 14 rads - 2 of which are off permanently-some are set to 2-3 and others high. I dont understand thermostats-am intelligent woman but the logic of it all always seems to befuddle me !