boiler, trv and thermostat settings

pinkbubblefairy

hi, sorry if this is in the wrong place....
needed advice about our heating settings.
we have:
ideal classic FF240 boiler
programmable timer
terrier TRV's on all but bathroom rad
room thermostat on landing

we have just had the room thermostat fitted to get more control over the heating - until now we just had the trv's which were set to 2 (about 18c) all round, but the boiler was constantly cycling, hence the new room stat.
we want the room stat at about 18ish (dont like it too hot!).
we keep all the doors open in our house most of the time so was wondering, should we set all the the trv's high, say 20 and the room stat on 18 and let the room stat control the whole lot?
the electrician who fitted the stat said we might as well turn the trvs on full, as we use all the rooms and keep the doors open, and the room stat will keep it all at out set temp.

also the boiler thermostat has a dial 1-6, is it best to set that high in winter- will the house heat quicker?

my aim is to economise on the gas as much as poss.

any advice would be appreciated

penrhyn

The room thermostat should be in your main living area, e.g your lounge.
Its next to useless having it on a landing where you need little heat.

Wind the TRV in the lounge all the way up and let the stat control it.

Set the other TRVs a little lower or as required.

Cardew

The boiler thermostat simply controls the temperature of the water in the CH system. So the higher the setting, the hotter the water and the quicker the house will warm up.

As you have a non-condensing boiler, there is no penalty in economy for having it set high - the main reservation is hot radiators(80+C) with very young children. With a condensing boiler(for others reading) it is more economical to have lower water temperatures.

With any wall thermostat and TRV combination of controls it is always a compromise. If you spend most of the time in the lounge, then it makes sense to control the temperature in the room with the lounge wall thermostat. However the downside of that arrangement is that if the lounge is at the set temperature, the CH is off. If you want to have heating in another room, say the bedroom where the radiators have been turned down/off(surely a normal arrangement during the day?) then, regardless of the TRV setting in that room, there will be no heat in that radiator untill the lounge thermostat demands heat and the CH fires up.

DVardysShadow

penrhyn wrote: »

The room thermostat should be in your main living area, e.g your lounge.
Its next to useless having it on a landing where you need little heat.

Wind the TRV in the lounge all the way up and let the stat control it.

Set the other TRVs a little lower or as required.

I disagree with this. If the temperature in the main living rooms is controlled by TRV, then this is good enough, it is not necessary to bring the main thermostat into this room.

A hall, downstairs, is a good place for a thermostat, provided it is slightly underheated either due to an undersized radiator or due to a manual control valve being set slightly low. The room should not have a TRV. The landing, however is not a good place, because hot air rises and landings have a tendency to get too warm, which means that the heating is shut off to keep the landing from getting too hot, but meanwhile the rest of the house is heading towards uncomfortably cold.

Canucklehead

Hi...see the Energy Saving Trust for advice on the optimum use of your heating/DHW and more.

HTH

Canucklehead

Cardew

DVardysShadow wrote: »

I disagree with this. If the temperature in the main living rooms is controlled by TRV, then this is good enough, it is not necessary to bring the main thermostat into this room.

A hall, downstairs, is a good place for a thermostat, provided it is slightly underheated either due to an undersized radiator or due to a manual control valve being set slightly low. The room should not have a TRV. The landing, however is not a good place, because hot air rises and landings have a tendency to get too warm, which means that the heating is shut off to keep the landing from getting too hot, but meanwhile the rest of the house is heading towards uncomfortably cold.

Like I said it is all a compromise!

I actually adopt your system, with a variation - I have the wall thermostat in a largely unheated hall set to maximum!

The disadvantage of this(and your system) is that the pump is running constantly when the CH timing is set to 'on'.

The temperature in all the rooms is set by the TRVs.

It is just not acceptable(to me)to have one room in the house controlling the temperature of every other room. e.g. Room stat in the lounge set to 20C - - room reaches 20C and no heat to any other room.

Mr_Ted

pinkbubblefairy wrote: »

we have just had the room thermostat fitted to get more control over the heating - until now we just had the trv's which were set to 2 (about 18c) all round, but the boiler was constantly cycling, hence the new room stat.
we want the room stat at about 18ish (dont like it too hot!).
we keep all the doors open in our house most of the time so was wondering, should we set all the the trv's high, say 20 and the room stat on 18 and let the room stat control the whole lot?
the electrician who fitted the stat said we might as well turn the trvs on full, as we use all the rooms and keep the doors open, and the room stat will keep it all at out set temp.

also the boiler thermostat has a dial 1-6, is it best to set that high in winter- will the house heat quicker?

my aim is to economise on the gas as much as poss.

any advice would be appreciated

A room thermostat fitted on a landing will shut the heat off prematurely due to as has been said the fact that heat rises and the landing is also the primary passage that rising heat will take.
The hall is the best place for a room stat as it is usually deemed to have the average temperature for the house!

With the TRV's set low it is unlikeley the house, as a whole, will reach the desired temperature, especially with the doors all open, hence the system is losing all the heat the boiler can produce, hence continuously ON!
Having the stat on the landing will save you but the ground floor will not reach the desired temperature on the stat!

Setting the boiler stat high will produce more heat for the output into the house and the house will warm more quickly, but it will use more gas initially to warm the house to the desired temp!

Personally I would have the room stat moved, or an RF one installed.
Use the TRV's in the bedrooms and the room stat to control the house as a whole, with the boiler stat on high!

unclebulgaria

A roomstat should be installed in an area that has a mean/average temperature. If you fit a roomstat in an area used continuously I.e. Living room, you'll find that it prematurely turns off the rest of the house in certain circumstances. T.R.V's are designed to control the temperature within a specific room so leaving your doors open is a crazy waste of your money. If you shut the door then that room will reach the temperature selected on the T.R.V and this operates the valves bi-metal spring to the off position. When this happens the water running through this radiator is halted and is not returned to the boiler for reheating, the less water your boiler has to reheat. Your boiler may have a pump overun facility, this will operate once the boiler has reached the required temperature, this keeps the heated water running around your radiators even though no flame is present inside the boiler.
Don't keep your boilers thermostatic control switched to maximum, you don't drive with your foot right down to the floor in your car unless you're nuts or don't care about your fuel usage. Set it at about 3/4 and get used to closing your room doors or you have just wasted your money having TRV's fitted. If you leave the house set your roomstat lower but not too low and again shut the doors. TRV's will never operate in a room with its door open unless the whole house has reached the TRV's setting. It is more economic to keep your boiler on all the time and control the houses mean temperature using the roomstat as this gives a gentle temperature curve rather than huge temperature fluctuations that keep your boiler working overtime. Try it, if I'm wrong I'll eat my Gas Safe Registration!

Cardew

unclebulgaria wrote: »

A roomstat should be installed in an area that has a mean/average temperature. If you fit a roomstat in an area used continuously I.e. Living room, you'll find that it prematurely turns off the rest of the house in certain circumstances. T.R.V's are designed to control the temperature within a specific room so leaving your doors open is a crazy waste of your money. If you shut the door then that room will reach the temperature selected on the T.R.V and this operates the valves bi-metal spring to the off position. When this happens the water running through this radiator is halted and is not returned to the boiler for reheating, the less water your boiler has to reheat. Your boiler may have a pump overun facility, this will operate once the boiler has reached the required temperature, this keeps the heated water running around your radiators even though no flame is present inside the boiler.
Don't keep your boilers thermostatic control switched to maximum, you don't drive with your foot right down to the floor in your car unless you're nuts or don't care about your fuel usage. Set it at about 3/4 and get used to closing your room doors or you have just wasted your money having TRV's fitted. If you leave the house set your roomstat lower but not too low and again shut the doors. TRV's will never operate in a room with its door open unless the whole house has reached the TRV's setting. It is more economic to keep your boiler on all the time and control the houses mean temperature using the roomstat as this gives a gentle temperature curve rather than huge temperature fluctuations that keep your boiler working overtime. Try it, if I'm wrong I'll eat my Gas Safe Registration!

Some points on your post.

As stated above, I agree that having the roomstat in, say, the lounge can cause problems i.e. lounge up to temperature on stat, so no heating in, say, bedrooms regardless of TRV setting.

However it is simply not always possible to have the roomstat fitted in a position in the house that has a ' mean/average temperature'. For many people the other locations for the stat is in the hall, and these days people simply don't want to heat their hall. In any case you have exactly the same problem with the stat in the hall i.e. hall up to temperature on stat, so no heating in lounge.

You seem to feel that if the pump is running, all the time CH is switched on, it is a big problem, but don't give a reason.

Also on the boilers thermostatic control again you make an analogy to a car driven flat out - which is not correct. On Non-condensing boilers there is virtually no difference in efficiency regardless of the water temperature.

On condensing boilers lower water temperatures, and hence lower return temperatures, will be of some help to greater efficiency. However it is not to stop them working 'flat out' like a car - which implies greater strain on the boiler.

Lastly can you explain your 'keep heating on all the time recommendation'. That is against all the advice to have the heating off as much as possible - for economy reasons.

For instance if the room with the stat is at 20C, and

1. You go out and turn the stat down as you suggest.

or

2. Turn off CH.

When you turn back on the CH, or the stat back up, how does using the roomstat give a 'gentle temperature curve rather than huge temperature fluctuations that keep your boiler working overtime.' ? and not turning on the CH. i.e. what is the difference in operation?

becksfaz

unclebulgaria wrote: »

It is more economic to keep your boiler on all the time and control the houses mean temperature using the roomstat as this gives a gentle temperature curve rather than huge temperature fluctuations that keep your boiler working overtime. Try it, if I'm wrong I'll eat my Gas Safe Registration!

More economical doesn't mean cheaper though does it??!
I was told this and so since my heating went on, I had it set to 'constant' and hall stat to 18. I then had a huge bill and came on here for advice.
Was informed in these forums to turn my heating off through the night and have it on for timed periods during the day, which I've done (Was difficult at 1st but noticing my useage descrease spurred me on!) and 2-3 weeks in now I've noticed a substantial difference in the my gas useage:
The week before Xmas I used 1231kwh in a week
(I have a bigish house consisting of large hall, big lounge/diner, kitchen, playroom, downstairs toilet, 3 bedrooms, office, bathroom and en-suite in master = 14 rads).
Last week (Monday to yesterday) I used 587kwh.
If you can advise me on how I can have the heating on more and keep my gas useage low then I'd really like to know.... cos having experienced both.... the more economical way, was the more expensive way!

foreversummer

I don't know if it helps, but I have a quite simple solution that works for me and my household (largish 4-bedroom detached).

1. We put the heating on only when we need it. (In our case morning and night at present)
2. Set the room thermostat at the lowest we feel comfortable with. (In our case 17 - 18 degrees)
3. Keep the TRVs at the lowest level each individual room feels comfortable with. (Somewhere between 2 and 4 on individual radiators)

If you feel cold nudge it up slightly and if you feel warm turn it down slightly at the room thermostat.

Simples!