CHANGE FROM WALL MOUNTED TO WIRELESS THERMOSTAT

[NOEYEDEERATALL]

I have a wall mounted thermostat at the top of the stairs where there is a radiator within 4 metres. As the location is relatively enclosed the heating doesn't seem to be working very efficiently.

Is there any mileage if I changed to a wireless thermostat instead and if I do how does that affect the wall mounted one?

I imagine I would have to get someone in to fit the thing?

We have wireless internet so would this cause any interference?

What else should I consider or should I just turn the wall mounted one up and sweat on the landing?

thanks
Neil

 

[Whitespirit66]

You have 2 problems with your stat location;

1) Being at the top of the stairs, heat rises, so will be warmer than downstairs. So the stat turn the heating off too soon, because the heat is accumulating at the top of the stairs.

2) The above will be made worse by being in proximity to a rad, and being a small area.

Room stats should be in the hall or lounge. They shouldn't be where they can be influenced by direct sunlight, or above/directly opposite a rad.The room where it is located needs to have rads without TRVs.

With wireless, you have a receiver fitted near the boiler or programmer, then you can put the stat/transmitter in the hall lounge. Won't affect internet.

If you are OK with wiring its possible to DIY (though your name gives a hint that you might not ), otherwise get a Part P qualified plumber.

 

[NOEYEDEERATALL]

Thanks Whitespirit66

Does that mean that the Part P qualified plumber just disconects the wiring from the wall mounted and fits it to the wireless receiver near the programer?

 

[Whitespirit66]

The plumber will remove the existing stat and wiring to it. The new stat has a receiver that goes near the combi, or wiring centre controls if not a combi, because it needs its own mains power supply as well as connection to the heating system.

The battery powered thermostat/transmitter is just screwed to the hall/lounge wall.Some models have free-standing transmitters that can be put on a table, etc.

 

[D_Hailsham]

I have a wall mounted thermostat at the top of the stairs where there is a radiator within 4 metres. As the location is relatively enclosed the heating doesn't seem to be working very efficiently.

A rad 4 metres away shouldn't cause any problems; it's the width of a room away. It's when you have the stat above the rad that you get problems.

Is there any mileage if I changed to a wireless thermostat

Not really. You need to find out why the system is not working as you want.

First thing is to check that the system is correctly sized.

Use Boiler Size Calculator to check the required boiler size.

Post the info and the Make/exact model of your boiler

Use Stelrad Elite Catalogue to find the output of your rads (manufacturers only vary slightly)

Post the info
Do you have thermostatic radiator valves?
Is there one on the rad where the wall stat is located?

 

[NOEYEDEERATALL]

The thermostat is based at the top of the stairs. The landing is a typical "reverse back" format to the stairs and leads around a corner to bedrooms. The radiator (with TRV fitted) is at the corner - it is normally set quite low because its one of the few rads which seem to throw out heat well.

I have been advised by the servicing people that ideally the thermostat should be fitted either in the hallway (again a rad plus TRV) or actually at the bottom of the stairs. This is because its more than likely to be the coldest positioning. I thought of the wireless stat because the current stat is hard wired and would involve quite a bit of disruption to reposition.

Neil

 

[D_Hailsham]

The thermostat is based at the top of the stairs.
The radiator (with TRV fitted) ... is normally set quite low

Neither of those are recommended.

Because heat rises, the thermostat could reach temperature before the ground floor.

If a TRV is set low, the TRV will shut the radiator off before the wall stat reaches the set temperature. So the wall stat may never shut off.

I have been advised by the servicing people that ideally the thermostat should be fitted either in the hallway (again a rad plus TRV) or actually at the bottom of the stairs. This is because its more than likely to be the coldest positioning.

They are correct. The rad in the hall should not have a TRV, but if you set it to Max you should be OK.

I thought of the wireless stat because the current stat is hard wired and would involve quite a bit of disruption to reposition.

That's a good enough reason; you should be able to do the whole job yourself.

Which make/ model boiler do you have?

Do you have an existing programmer/timer - if so which make/model?

 

[NOEYEDEERATALL]

Thanks D_Hailsham

The rad I mean is on the landing at the top of the stairs. I have shut this down to about setting 2 because it gets hot and I don't want the stat to turn off as a result.

The boiler is only about 4 years old and is a Vailant thermoCompact.

The timer was new this year and is a Drayton 7 day.

The stat is a basic dial model but I am unsure of the make

 

[D_Hailsham]

The rad I mean is on the landing at the top of the stairs. I have shut this down to about setting 2 because it gets hot and I don't want the stat to turn off as a result.

Understood. However, when you install the thermostat downstairs, the TRV on the rad in the hall will either have to be replace by a standard valve or set to Max.

Thank for the info about the boiler, programmer and stat.

Your best option is the Honeywell DT92E wireless thermostat. There are two components: control (transmitter) and relay (receiver). The control would go in the hall and the relay can possibly go where the existing thermostat is as you may be able to use the existing wiring. It's easy to check this.

Remove the stat from the wall and check how many wires are connected to it. If there are three you should be OK. The wiring is usually given on the back of the stat. Post the info, including stat model no.

 

[NOEYEDEERATALL]

There are 4 wires actually but the earth is not conected at all.

The wall stat doesn't have any form of identification at all apart from a interlocking C and t symbols which are at 90 degrees rotation to the right (??)

There are 4 possible slots for the wires to go into

The wires are as follows:

Brown live and goes into slot 1

Grey neutral goes into slot 4

Black (switch to boiler/pump apparently) goes into slot 3

 

[D_Hailsham]

Brown live and goes into slot 1

Grey neutral goes into slot 4

Black (switch to boiler/pump apparently) goes into slot 3

I'm sorry but I misled you. The DT92E needs four wires, not three. You could get away with it by using the earth wire, provided you put some red sleeving on it to show it is a live wire, but it's not kosher.

Does the cable from the stat go back to a wiring centre (large junction box)?
If so it's just a case of swapping some wire around and connecting the "earth".

If that's not possible you will have locate the relay box near the boiler and abandon the existing thermostat.

 

[NOEYEDEERATALL]

I have no idea at all to be honest.

I have "phoned a friend" who said that

1) Brown live goes to first L

2) Then a 1mm wire loop needs to go from L to L

3) Then a 1mm wire loop from second L to A

4) Then the black switch goes to B

I dont understand about the strange link from A to C as shown in the diagram below (which hopefully I have attached but it doesnt seem straight forward to me to load it)

 

[NOEYEDEERATALL]

Untitled

• NOEYEDEERATALL
• 25 Nov 2010
• 1

 

[D_Hailsham]

I have no idea at all to be honest.

Why not have a look? The junction box will be near the HW cylinder.

I have "phoned a friend" who said that

1) Brown live goes to first L
2) Then a 1mm wire loop needs to go from L to L
3) Then a 1mm wire loop from second L to A
4) Then the black switch goes to B

That's not correct.

At the moment, the brown wire is fed from the CH ON terminal of the Drayton timer. So it is only live when the heating is ON. The connection to the relay L terminal must come from a permanent Live supply.

The correct wiring is:

L - Permanent Live
N - Permanent Neutral
A - Timer CH ON
B - Boiler

I don't understand about the strange link from A to C as shown in the diagram below (which hopefully I have attached but it doesn't seem straight forward to me to load it)

That's a two-way switch. It means that A connects either to B or to C. B is used for heating applications; C for cooling. So you can ignore C.

 

[NOEYEDEERATALL]

Thanks for all your help D_Hailsham.

One last set of questions Im afraid.

What does it mean by binding / rebinding. Does it mean to link the relay and the wireless stat together? In a way a bit like hooking up a laptop to a wireless internet box via the IP addresses etc?

Also what does it mean by heat/cool changeover please?

By the way I have connected as per my friend's instructions and it seems to be working ok...