Honeywell wireless thermostat lost comms

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Yorkshire
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Hi

We recently had a new boiler fitted and it was fitted with a Honeywell CMS921B1042 wireless thermostat but it has lost communication with the boiler and the red light is just flashing on the box by the boiler. I know that it's just a case of pushing some buttons but I don't know which ones and in what order so that I can get the wireless comms back.

Hope it makes sense can anyone help.

Cryax
 
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Thanks for the reply,

I probably should have explained better I went through the instruction book and the only refrence I found to the problem is in the troubleshooting section on page 15. It basically says to either relocate the thermostat which makes no difference or to call your installer.

This is the second time this fault has occured the first time we called out the installer and he fixed it but all he did was press a button for several seconds on the box by the boiler and then did something with the thermostat itself he was here no more than 5 mins. He is currently Ill in hospital so can't do it again so I was hopeing that someone might be able to explain how it is done as it only requires a few button presses but I can't find any instructions on what button presses are required.

Thanks

Cryax
 
Batteries could be faulty.

If it is the same receiver as the one used on the cm927 then you just press the 'test' button failing that turn off the power to the receiver/boiler then turn it back on again and then switch on the stat or switch it off first then switch it on.
 
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Take your programmer/stat to within one meter of boiler and take out batteries, now replace them, does this solve the problem.

BTW, Are you using wireless internet connection :?: , as some RF units are affected :idea:

;)
 
Hi Thankyou for the replies,

I tried all of the above but no joy I,m afraid I do have a wireless router but the wireless function is currently disabled as I prefer to use it with & ethernet cable.

I found this on the internet which is for the thermostat I have http://europe.hbc.honeywell.com/products/pdf/en0h8556uk07r1006.pdf

Now it tells me how to get in to installer mode but not how to do the Wireless assosiation I dare not just fiddle with it as I don't know what the options do. I think what I need to do is what a fitter would do when first installing the device and I assume it works in a simaller way to wireless devices for the pc etc it's just a case of knowing what buttons to press and options to select.

Thanks

Cryax.
 
Just press the test button on the receiver don't do anything with the stat/controller.

The receiver is fitted at the boiler it is white box with a small button and when demand is called for there will be a green light on.

If a red light is showing you have lost the signal so press the small button.

See my previous post for further instructions however if all of that doesn't work then you need a new controller.

I've fitted about 60 of these in the past two years and only one has failed,so far.
 
Hi I did all that but again no joy.

I just remember when I had my installer out the first time this happened that he solved it by doing something in the setup options. He held the small button on the reciever in for awhile I just tried that myself and after 15 seconds or so the red light flashes differently to how it did before I just haven't got a clue what he did next but it was something to do with the installer mode on the thermostat. he also pressed the small button on the reciever again after that I think.

Thanks again.
Cryax
 
You don't have to go into the installer setup to get it them both to 'talk to each other'.

You can try that if you want but I suspect your controller is gubbed.

Easiest way out of this tonight is to remove the receiver from the boiler (electrically) and then reinsert the link from the removed receiver terminals on the boiler and then use the boiler with just it's own time clock or controls.

Tomorrow or tonight buy another controller from ,

http://www.heatingcontrolsonline.co.uk/index.php

or your own supplier then just fit the new receiver to the old receiver's mounting plate (after reconnecting it to the boiler) stick the batteries into the new controller and your sorted.

Then either go back to your original supplier with the old kit or wait a few days and return it to the new one for a refund telling them that it was faulty.
 
Ok thanks for your help the boiler is working manually. I have a Green light if I press the little button on the reciever it goes of if I press it again the red light is always flashing so it's not talking to the thermostat. I'm not confident enougth to mess with the electrics and I also have a two year waranty and wouldn't want to void It. I will probably have to wait for my installer to get better.

Thanks again

Cryax.
 
You just need to remove two wires and insert a link where those wires were on the boiler terminal strip and you will be back in business.

You don't even need to fit a new controller you can just work the boiler manually with the controller removed until yer man is better.

Personally I wouldn't wait and neither would I expect my customers to wait for me either in similar circumstances.

Just call out an Electrician to fit the new controller and sort things out with yer man when he is better.
 
installation manual said:
To check the RF communication, hold the room thermostat about 2-3 metres from the installed receiver box. Move the slide to OFF then press the temp up, temp down and right arrow[ buttons together for 3 seconds. The unit will display Test Transmit and will send test signals to the receiver box, flashing the green light on every six seconds (the relay will be off so the boiler will not go on and off.

Moving the slider to another position will stop the test

If the green light is not switched on and off or you get a red light flashing you need to rebind

Installation manual said:
1. Press and hold button on receiver box for 15 seconds. After 15 secs the red will flash 0.1 secs on/0.9 secs off (Note: after 5 seconds the light will flash 0.5 sec on/0.5 sec off, but continue to hold the button in)
2. Release the button
3. Press the receiver button for 5 seconds until it flashes 0.5 secs on/0.5 secs off.
4. Move the slider to OFF then press the temp up, temp down and left arrow[ together. The unit will display InSt and "Control Binding"
5. Press the Green OK button to send a signal to the receiver. The red light should go out. If the red light does not go out, press the OK button until it does.
If this does not work one of the components is faulty, or the batteries are dead.
 
D_Hailsham your a star thats exactly what i needed and it worked I guess thats what my fitter did the last time it went. As a customer I wasn't left the installer manual only the instrution book.

On a side note is the fact this has now happened twice the sign of a fault or is it just something that happens from time to time.

Thanks again

Cryax.
 
On a side note is the fact this has now happened twice the sign of a fault or is it just something that happens from time to time.
Can't give you a definite answer on this one.

Apart from being a fault, I was thinking that it could be caused by the transmitter being near the limit of its range; so the signal is not always received. The receiver will turn off if it does not receive a good signal from the transmitter.

Try relocating the transmitter or the receiver.
 
I've fitted these in all sorts of houses with boilers in lofts and cellars and never had a problem with range only problems have been batteries and the odd one that just wouldn't bind to the receiver so replaced it.
 

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