Programmable thermostats

[Armo74]

Hello,

I was wondering if anyone could explain a little more on how these work please. As i understand it you can use them to set specific temperatures for different times of the day.

Do you have to have the programmer constantly on?

Are they suitable for all types of heating systems?

How much different are they to normal dial and digital room thermostats?

Thanks in advance.

 

[Barry98]

Is there something specific you've got in mind that you want one for ?

 

[Armo74]

Thanks for the reply bod, Nothing specific just like to know how these things work.

 

[Barry98]

Hello,

I was wondering if anyone could explain a little more on how these work please. As i understand it you can use them to set specific temperatures for different times of the day.

Do you have to have the programmer constantly on? Yes if your going to be using it

Are they suitable for all types of heating systems? Pretty much there's one for each

How much different are they to normal dial and digital room thermostats? Less to install

Thanks in advance.

My opinions after your

 

[stratobuddy]

I am familiar with 2 vaillant types.

They can control CH for 3 different ON times per day (and therefore 3 off times as well), and one can do the same for DHW.

It can be set for different programmes for days away, and also for holidays, up to a year in advance!

One will control the temp of the DHW as well as the CH (obviously they both control the CH temps).

There are loads of boiler parameters that the installer can set in addition to the user options, protected by a pin number.

The 392f is VERY complicated for the ordinary customer to use, IMO. The 470f is much simpler, but is a weather compensated controller so that brings its own problems for the customer eg luke warm rads.

PS the USER operating manual for the 470f is 42 A4 pages, the INSTALLER manual is an additional 54 pages ! ! !

 

[snowhead]

I've had one for 24 years in my own house, still the original one.

Mines a basic one, I can set 4 different temperature changes during the weekday, and 4 at the weekend.

It's got override for 1, 2, or 3 hrs advance and frost only for holidays.

Consider it just the same as a standard time programmer but it changes the temperature setting of the stat at the appointed time instead.

 

[Armo74]

Thanks for the replies guy's, that has shed a bit more light on it for me. Do you come across many of these on the job? I only ask because the normal room stats seem more popular, Maybe because they are easier to use and understand.

 

[Barry98]

Finding a lot go for them in rf , rather then hard wiring

 

[Armo74]

Thanks bod, I assume rf means wireless?

 

[Barry98]

Yes fella sorry, radio frequency

 

[Element]

I fit them all the time on combi boiler installations. Be aware some of them are a bit complicated for some customers I've found the Honeywell CMT is the easiest to use. There are no set on off times just temperature ranges so when you don't want the heating on say at night just set the temperature down to 10 degrees.

 

[petercj]

Hello,

I was wondering if anyone could explain a little more on how these work please. As i understand it you can use them to set specific temperatures for different times of the day.

Do you have to have the programmer constantly on?

Are they suitable for all types of heating systems?

How much different are they to normal dial and digital room thermostats?

Thanks in advance.

If you're looking to cut your gas bill, I recommend getting a digital wireless room stat - I fitted one and it paid for itself in the first half of winter.

The one I have has manual control, or you can program it to change the temperature at different times of the day and night - each 24 hours being sectioned up into blocks of time which can be set to run at a chosen temperature.

So for example on auto, 5pm to 11pm might be set to 21c, and then 11pm to 5am can be set at a lower temperature, say 18c during sleeping hours. Or off at night it if that is what you want.

I use ours on manual and just keep it in the lounge during the day, and in a bedroom at night.

It allows you to have far more control than a fixed room stat, and with a few adjustments I was able to cut our gas bill by 20% last winter - BG had to pay me money back, which was nice.

They can be troublesome, so well worth getting one with a 2 warranty.

Fairly easy to fit yourself, or get someone to fit one for you if you feel unsure of doing it yourself, and then if it goes wrong remove and fit a new one yourself - dead easy to swap over once fitted.

 

[stratobuddy]

Yes, I forgot to say that a radio controller (rf) can be moved around the house. The 470f has a wall bracket that the controller just clips on to, and can easily be removed again.

So you could have it in the living room set at, say, 20 during the day, then take it up to the bedroom at night and set it to 18, for example.

So it will be controlling the room you are actually in, this may be a good selling point.

But the 470f costs about £175 !

 

[CES]

Yes, I forgot to say that a radio controller (rf) can be moved around the house. The 470f has a wall bracket that the controller just clips on to, and can easily be removed again.

So you could have it in the living room set at, say, 20 during the day, then take it up to the bedroom at night and set it to 18, for example.

So it will be controlling the room you are actually in, this may be a good selling point.

But the 470f costs about £175 !

What would be the point of that?
Assuming you would be upgrading the heating system which would mean TRVs and a Thermostat, what would be the point of taking the thermostat upstairs? The TRV does this already, by moving the thermostat you run the risk of the thermostat and TRV fighting against each other and the heating being on all night.

 

[stratobuddy]

Because turning it down to 18 in living room may mean bedroom never reaches 18 because of smaller rad. Leaving it at 20 to get 18 in bedroom would mean living area would be too hot at night.

 

[CES]

Just out of interest, have you got TRVs installed?

 

[Armo74]

Thanks for all the detailed explanations guy,s.

 

[Armo74]

If that post was for me CES then yes i do except for the one with the room stat in.

 

[stratobuddy]

Just out of interest, have you got TRVs installed?

Yes, on most of rads, but leave living room fully open and let the controller do the controlling, with the WC it gets boiler well into condensing mode too.

 

[petercj]

The way I use my wireless stat in the winter involves reducing the heat in the hall 24/7 (where the old stat used to be) and turning off the large double radiator in the lounge when going up to bed, and taking the stat up to the bedroom.

Simple enough but very effective in reducing the consumption of gas by 20%.

 

[CES]

Well, in that case don't buy an RF stat and move it around the place or you will confuse the hell out of the boiler as the rad without the TRV is where it gets its read back from.
Programmable stats are fine, I have one myself and they do save money but you have to be aware of how they work in order to get the best use out of them.

 

[Dotty]

And yet you are over heating the rest of the house with this 'compensation' because your bedroom rad is undersized!

Leave the stat where it's designed to be. the reason it's wireless is to prevent having cables every where. Not so you can go marching round the house with it!

 

[Armo74]

Would it be safe to say that the programmable thermostats are compatable with most programmers? Or would it be a case of checking they are compatable first?

 

[Dotty]

You don't need a programmer with a wireless stat, the receiver is wired in to the wiring centre.

 

[CES]

Yes, on most of rads, but leave living room fully open and let the controller do the controlling, with the WC it gets boiler well into condensing mode too.

I would leave the controller and the TRVs to do their job as, for instance, if you moved it to the bedroom and the TRV was set to 16 and the Stat was set to 18, the boiler would be constantly on looking to achieve a temperature that the TRV is preventing it from reaching.

 

[petercj]

If there's a TRV in the room with the stat open it up to maximum.

You don't need to match the make of the stat with your other controls, Drayton and Honeywell are pretty good, which is reflected in the price.

 

[Armo74]

Sorry for all the questions guy,s but what makes the digital stats more efficient than the dial ones that some have a bi-metallic strip inside? Is it because they are more accurate to say 1/2 a degree?

 

[Armo74]

You don't need a programmer with a wireless stat, the receiver is wired in to the wiring centre.

Thanks for that croppie, It was what i couldnt get my head around the fact that the programmable room stat was not only a thermostat but is effectively doing the job of the programmer as well, would i be correct in saying this?

Or on an open vented system do they have control over the hot water as well?

 

[stratobuddy]

The receiver is wired into the boiler as you say, but the programmer tells the boiler what to do. With a weather compensated controller it even tells the boiler what heating curve to use.

 

[petercj]

If you upgrade to a digital room-stat the basic function will remain the same, i.e. it will switch the heating on and off in relation to a chosen temperature.

If you upgrade to a digital room stat that is programmable then it will have a clock built in that enables you to preset times and temperature. However, your main central heating controls will remain the same as before, and will override the room stat as they did before if set to do so.

A wireless digital room stat will come with a receiver that can probably be wired to the existing wires that connect to your static room stat (although you may need a permanent live), or it can be connected into your wiring centre - which is likely to be the best option if you don't have a permanent live at the site of your existing room stat.

Although a programmable room stat will work independently of your main boiler programmer, you could say that the added functionality serves to duplicate some of the features of the programmer.

 

[Armo74]

Just one more question on this subject, what might you need a permanent live for?
Again thanks very much for the responses.

 

[Mike Jackson]

To stop the missus changing the settings.

Generally required for the receiver.

 

[petercj]

The receiver has to receive signals from the sender and switch power on and off, and it needs power to perform such functions. The sender is powered by batteries.

You can get a receiver now that will take signals from the Internet which have been sent via an iPhone if you want to wind up your other half from the office.

If you don't tell her how it works, she'll think the place is haunted! lol