How to fit a wireless room thermostat | fit Honeywell wireless thermostat

www.ultimatehandyman.co.uk/for... shows how to install a wireless room thermostat to a combination boiler. Wireless room thermostats can often save fuel as they keep the room at the exact temperature that you require. The model fitted in this video is the Honeywell CM921 wireless programmable room thermostat.

[@shugipop]

Thanks so much I've struggled for weeks to get the remote sensor to work only to realise I hadn't reset the thermostat all working fine now saved me calling out the boiler guy. Thanks a bunch 😊

[@ultimatehandyman]

+shugipop You are welcomeThanks for the comment

[@chunkymonkey55555]

Just had a Wireless Thermostat fitted by a plumber, this is the best video around telling you how to do it. Only issue we had was working out which connection to put it into in the boiler. Good job mate.

[@ultimatehandyman]

Thanks for the comment ;-)

[@chunkymonkey55555]

I bought a Honeywell Y6630D Wireless Room Thermostat, which only has a turn wheel type of dial on it, no fancy digital display or anything. So working out if it goes into the 230v connection or the eBUS connection wasnt as easy to work out as you might think :) Works fantastic now in, well worth the effort!

[@imranmajid1978]

Perfect example of how to achieve best-practice when wiring; the time and effort in perfecting those cables is excellent.

[@ultimatehandyman]

Thanks for the comment

[@subrjs]

Nothwithstanding the bit about soldering; the actual 'stat installation was very informative. Thanks

[@revanslacey]

Wow! Voltmeter, soldering, heat resistant wire, shrink fit stuff, clips, trunking. It like going ice skating then watching Torvill and Dean! Proper job!

[@simonbuenosaires]

i havent done it yet but ive been thinking how to do this for a while, and your clear instructions are very helpful i will have a go, thanks for that, great videos your have

[@jamire36]

Excellent instructional video, I just installed one of these on a Ferroli combi boiler and the most difficult bit was fitting the trunking and drilling for the wall box! Very simple wiring even for a DIY enthusiast like myself. Prior to this we had no thermostat so were controlling the temperature in the house with thermostatic valves and by turning the boiler on and off which was hopeless! 3 days on we only have the boiler on half of the time and the temperature control is effortless. Top marks for the video, and chuffed to bits with my Honeywell Chronotherm unit. Always sceptical of the range of RF, but our transmitter unit is working fine 2 rooms away from the Relay box in an old house with solid stone walls. My only regret is not fitting it last year and reducing the amount I contribute to the profits of my gas supplier!

[@ultimatehandyman]

Thanks for the comment ;-)

[@malachy1847]

***** Just wondering at 10 mins -20 secs in the terminal where you fitted the switching cable is block 72 where the link was .....correct..

[@ultimatehandyman]

Yes, the switching wires replace the link. The relay from the wireless receiver then opens and closes this circuit to switch the boiler on and off.

[@malachy1847]

***** Great upload always wondered how to get my head around this wiring loop... now i'm sorted... [ Because of the digital control introduced there's reckoned to to be a fuel saving of 10% plus ] thanks again....

[@RopeyrhymeLetts]

This upload from Ultimate Handyman is a first class informative presentation.

[@ultimatehandyman]

Thanks for the comment ;-)

[@markhemps]

Thanks for making these videos they are exactly what i needed and they saved me a heap of money..

[@atakd]

Very helpful. I wanted to do the reverse and the heads up on fitting the bridge saved the day.

[@ultimatehandyman]

Thanks for the comment

[@lordshoa]

Thanks Great tutorial came in handy. Almost missed the double pole switch part as my boiler only had a spur unit in there not sure if it was double of single but changed it out for a double pole switched spur just in case. I installed mine on a Baxi 35/60 was same install only thing I figure out, was I had to turn the temperature dial up on the boiler for it to start working was not sure if it was supposed to be up or down to start with, but now I know and hope it helps others.

[@mrqwerty65]

Every video you post is a corker. So much information and easy to follow content. You are a marvel...

[@ultimatehandyman]

Thanks for the comment

[@ArksE8]

You've been more helpful then a electics tutor. Vids are great

[@ultimatehandyman]

Thank you ;-)

[@RobsRepairs]

thank you, think i blew up my pcb by applying 240v to the switched live circuit, but this has helped me narrow down the fault finding, wish i had just done more research and watched this first :P cheers.

[@jasondavies1009]

Enjoy watching your videos and you explain things in a easy to understand way keep up the good work

[@ultimatehandyman]

Thanks for the comment Jason 👍

[@PS3Bloodykittens]

I won't be installing a new thermostat anytime soon, but this video is still VERY informative. Great Video :D

[@bilalpatel324]

Just what I was looking for great video. Keep up the good work very helpfull

[@calmdragon]

After watching this video i realised you are waaaaaaay smarter than me , and i am calling an electrician !!! lovely video btw

[@danielculverwell2940]

Great video and it was great to see the job as it was very much what i was thinking it would be in my head. I got a price from my boiler service co. and they want £230 to do the same job!!! I was a little unsure as i have not done one before and thought it would involve messing about with the boilers timer switch - In fact its very simple to do and the hardest part of the job will be fixing the receiver to the wall. Thank You for the Video

[@user-kq1ye6bg5h]

Brilliant. Suggest if you can’t get the green light flashing green, move the thermostat closer and try again. Worked for me.

[@ultimatehandyman]

👍

[@puskycip]

hi guys. guess what!... done mine and .....success. It works. We did it!!! we did it!!...I mean I did it. Really it was a piece of cake. The guys who made the boiler were so clever to fit the room thermostat connectors outside on the back of my boiler's control panel. it was so intuitive. had to check first anyway the boiler's electric diagram. I had a clue of what I'm doing but your video was so reassuring. thnx ultimatehandyman

[@BeardyRebel]

I've just changed my Worcester Bosch stat to this exact same Honeywell model and it's so much better. Mind you, this was one job I left to the boiler installer ..... LOL

[@djscottfrenzy]

Very Good instructions there. Very helpful Cheers

[@ultimatehandyman]

You are welcome Thanks for the comment

[@vbfg1973]

Thanks for this mate, very helpful. My model of boiler too.

[@ultimatehandyman]

You are welcome. Thanks for the comment ;-)

[@whoislaurie5371]

Thank you so much for this video. So helpful... our property manager didn't help and we had no heat for almost 3 days 🙃

[@ultimatehandyman]

You are welcome Thanks for the comment 👍

[@RoadManilla]

Cheers this made, this made it wonderfully easy.

[@332marian]

Great video really well explained.Take my advice though and get a new boiler.👍👍👍

[@ultimatehandyman]

That boiler didn't last long after making this video, I think something failed on it a about 12 months later and it was cheaper to buy a new boiler. It lasted about 13 years from new. Thanks for the comment

[@brookybrook3725]

Oh and flipping brilliant channel by the way! You saved my dishwasher the other day !!!

[@tarrytarry]

Excellent video. Very well explained.

[@lennyfearon3243]

Excellent tutorial … many thanks

[@ultimatehandyman]

Glad it was helpful!

[@Steve_W27]

Thanks for the video - very clear and Im glad I came across it as Im going to install one of these over the weekend. Just 2 quick questions if you dont mind - the instructions for the Thermostat say that you need to use 1.5 - 2.5mm2 core flex. Do you think its ok to use just use 0.75mm2 flex? Also, did you use the same cable type for both the power and the switching cables? Sorry if they sound like stupid questions!

[@Steve_W27]

Wow - that was a quick reply - thanks very much for your help! I forgot to say - what a coincience this video is, as that boiler is almost identical to mine, I've got a Ferroili 'Modena' - very similar, so your video was very handy.

[@708mrmike]

Wonderful, kind regards Mike👍

[@garryfawcett3304]

Very informative and well presented video thanks

[@ultimatehandyman]

I’m glad you found the video useful Thanks for the comment 👍

[@rowlster1791]

Fantastic video. Thank you!

[@ultimatehandyman]

+Leon Rowland (Rowlster71) You are welcomeThanks for the comment ;-)

[@njuham]

Pure poetry, mate.

[@mickdundee3411]

cool video. thanks

[@AdnaneLondon]

Well explained thank you for sharing ..

[@ultimatehandyman]

AdnaneLondon You are welcome Thanks for the comment

[@Razittee]

Great video. I have them fitted and working last year. The heating was switched off during the winter but now the thermostat is not communicating the receiver, what could be the reason. I have tried reseting the thermostat with no luck.

[@criticaljack3391]

Sir you are great,thank you so much for your video. :)

[@ultimatehandyman]

You are welcome. Thanks for the comment ;-)

[@1justpara]

Thanks for this. My dad has one of these and it lost it's connection and we could not find the instructions. I've reset it once before but without the instructions to tell me which buttons to press for 3 seconds I was unable to reset the connection. Now I will be able to go and fix it again for him. Many thanks once again.

[@10rab2k]

recently had a really bad lightning strike mid year and took out power to boiler had a rough guess that it was the internol boiler fuse was just woundering for futcher refrance are thay located on the pcb panal and easy to replace if ever happens again nice upload can now get my timer up and running now :)

[@parkinio1]

I have an update.It is ok to remove the boiler cover if not Gas Safe Registered but on some boilers the cover has a seal around it and you do have to be Registered to remove it.

[@fielding68]

Great tutorial. Thank you.

[@ultimatehandyman]

You are welcome Thanks for the comment 👍

[@alfiecane]

Great little video thanks 👍

[@ultimatehandyman]

You are welcome. Thanks for the comment ;-)

[@druid1980]

Great video. How do I know which way round to get the switching cables on the boiler? Thanks

[@kdcoops]

Great video, very helpful.

[@ultimatehandyman]

Thanks for the comment 👍

[@teslasparksloughborough9963]

This sounds like a good idea. Just looked on Ebay they cost about £120. One more lazy labour saving gadget.... Gonna buy one... Thanks for the install video..

[@ultimatehandyman]

You are welcome Thanks for the comment

[@David5495]

@9inety9 It's a CM921 so you can set it to automatically come at different times at specific temperatures throughout the day e.g. 0800 - 20ºc, 1130 - 16ºc 1830 - 21ºc 2330 - 15ºc and so on... The CM927 allows you to set different temperatures and times above but for every day of the week. If you just wanted a simple wireless stat without all the timing features then I would get the DT90E.

[@dannyburleigh]

Sparks, myself...good video. no need to heat shrink, just mark mains and aux.

[@ultimatehandyman]

Thanks for the comment ;-)

[@dinosauraccounts1411]

Excellent video. I have a ferroli boiler.. similar diagram to yours. The clock in the boiler is faulty if I replace with a wireless thermostat and receiver can I just take the clock out

[@aamirkhan1846]

great video..thanks for uploading.very helpful and easy to follow.

[@ultimatehandyman]

+Aamir Khan You are welcome Thanks for the comment

[@aamirkhan1846]

+Ultimate Handyman I have a 24 hour timer switch installed for central heating(as. we dont have built in timer on our boiler).I want to put in a wireless thermostat.will same wires that come out of the timer switch go into the wireless thermostat?

[@ultimatehandyman]

+Aamir Khan I don't know, probably best to ask here- www.ultimatehandyman.co.uk/forum1/central-heating-boilers-f35.html With as much information as possible ;-)

[@aamirkhan1846]

+Ultimate Handyman Thanks pal

[@ultimatehandyman]

+Aamir Khan You are welcome ;-)

[@Lagunasaxoxr2]

Great upload! I got a quick question..... If you had a powercut and then the power came back, would the wireless connection be lost between the transmitter and receiver? Would you have to pair it again?

[@Pithead]

Excellent! I've just bought one of these for a Baxi 105 HE. Pity it has to be 30cm away from metal because I had intended on siting and wiring the receiver right next to the boiler's fused spur (which is very close to the boiler. I think I'll test it there anyway, otherwise it's a short run up the wall. Great vid!

[@ultimatehandyman]

+Noth Ankyou I have just checked the boiler here, which has the exact same unit. The installer has it positioned about 5cm away from the boiler and we have had zero problems ;-)

[@Pithead]

***** Cheers for that. Hopefully mine will be OK then. I'll give it a week's test and let you know how it goes. Keep up the great vids!

[@ultimatehandyman]

+Noth Ankyou You are welcome. Thanks for the comments

[@Pithead]

+Ultimate Handyman It's been operating fine for 3 days at exactly 100mm from the side of the boiler housing so I fitted it. Thanks for the tip!

[@ultimatehandyman]

+Noth Ankyou Good stuff ;-) Thanks for the comments

[@fatboon]

great vid, i had this thermostat fitted with a new boiler at our old flat. we have a house, which has a newer ferroli f24, but the diagram is identical to yours as is theu clock. now you have this installed, do you use the clock on the boiler to program it, or the stat? also does this overide the clock.

[@scottyboymu]

For reference any live or switched live conductors should be marked with brown tape unless there is no chance of confusing.. and all multi cables containing 230V should be earthed

[@puskycip]

hi. great video there. i've got a different type of boiler and thermostat but i see the principle it's the same. i'm going to do mine by myself but if I screw up someone's going to get a hurt real bad.

[@AZKHAN12121]

@ultimatehandyman Hiya, firstly a brilliant upload. Thanks alot. Now here is my problem. I have converted my house into two separate flat. Both of the flat has one boiler, as im living in one of the flat, i only have access to that boiler and not the other person living in the other flat. Would you suggest that I put a wireless thermostat in the other flat so the other person can also control the central heating system? What would you suggest? I am confused! Thanks

[@Czarny9121]

Hello there this is a nice video , I just would like to ask if the CM921 and R6660D are compatible or not as I have a different receiver than yours which is Honeywell R6660D.

[@mo-gc3ik]

very good explanation

[@ultimatehandyman]

Thanks for the comment 👍

[@georgeklug481]

Perfect option for anyone on a budget.

[@ultimatehandyman]

👍

[@TheTriggsyboy]

spot on watched your upload and it was done great have now done mine and found it so easy so once again spot on well done

[@sachin1kapoor]

good video bud, perfect for a layman like me but you didn't show how to wire the Thermostat main box which wire to go were.

[@jack89fisher]

Evening mate. Firstly, thanks for the upload. It's exactly what I was looking for. Very informative. Secondly. Do you by chance know if a Honeywell Thermostat like yours would work with a Viessmann boiler?

[@ultimatehandyman]

Hi, Not sure without looking, your best option is to post here with as much info as possible such as the exact model of the boiler- www.ultimatehandyman.co.uk/forum1/central-heating-boilers-f35.html Thanks for the comment ;-)

[@RichardNash100]

hi can you do a video for wiring up a two port valve controlled by a wireless thermostat to remote control central heating only - someone told me it doesnt need to be connected to the boiler as i dont want to mess anything on the boiler up just a request i need some help with cheers in any event all the best all the videos you put u are great :)

[@quietsparks1]

Very easy, I just connected mine and it work beautifully. thank you very much. If you dont mine me asking, what accent is that, I mean where are you from in UK?

[@mikeysky8917]

Can I use these Honeywell wireless thermostat's on an Oil boiler which I have outside? Many thanks for the useful videos btw.

[@miaji1963]

Great explanation super

[@ultimatehandyman]

You are welcome Thanks for the comment 👍

[@tanveerkhan9221]

Good explanation best to use bootlace ferrules on stripped cables

[@ultimatehandyman]

Thanks for the comment 👍

[@baddass888]

Very nice mate.... Being a sparky yeah you could have earthed the cable - no harm In doing so - and one last point on the two white cable entries you could have had them the other way around so the cables weren't crossing over each other.. apart from that great vid pal :p

[@ultimatehandyman]

Thanks for the comment, Ben ;-)

[@acrestones]

helpful video thanks a lot

[@ultimatehandyman]

You are welcome Thanks for the comment

[@mufc99ok]

hi im getting used to heating programs in the uk ,s, y palns etc , so need to feed the reciever first and the the room stat does the rest for ya, i would have ran a 4 core from the reciever thats just me but what ever suits eh

[@sannisalisu3146]

Thanks for the video. Its helpful. Just a quick question though. Do you connect the live supply for the reciever box from a fused spur first or all connections is taken from the boiler? Thanks

[@ultimatehandyman]

Sanni Salisu You are welcome It's often easier to take the supply from the boiler. (the boiler should be connected to a fused spur), so once the fused spur is switched off it isolates the boiler and the receiver. It's normally easier to wire that way as you have to wire the switching pair to the boiler anyway.

[@ashvanbro9329]

Great video brother spider junction

[@ultimatehandyman]

👍

[@subrjs]

Tinning wires fixed under screw terminals is not a good idea. When you tin a multistrand wire fully, the solder wicks between the strands of copper and forms a solid block, part of whose volume is metallic solder. When you clamp the solder and copper bundle you tighten the screw or clamp against the solder block, and in time the solder metal "creeps" under the compressive forces and the join loses tension. The wire can then either pull out or cause a high resistance connection with heating.

[@windowscleanedtodayltd7478]

hi there I have a Worcester boiler with the same transmitter but the buttons don't work very well but all I have to get a new wireless transmitter with the LCD screen do I just connect it wirelessly as you did when you put it into test mode with the existing wireless box or do I have to get a new wireless box and receiver fitted to my old boiler. Question mark thank you

[@fatboon]

hi, i finally got round to fitting one of these to my ferroli f24. identical connections to yours, but mine only works if the clock is in the I position. the thermostat bit is working, but i find the pump is running constantly. does your pump cut out when you switch it off

[@Pat19eighty4]

Great video, do you have to disconnect the existing boiler programmer if there's one integral to the boiler as is the case with some boilers?

[@ultimatehandyman]

+Pat19eighty4 I think you can just switch the programmer to manual, that should mean that the wireless thermostat takes over. Thanks for the comment

[@ArksE8]

Thanks for the response.

[@ultimatehandyman]

+Arks Shackerwell (ArksE8) You are welcome ;-)

[@BackDaws]

I've got a salus wireless thermostat that's playing up, can I just buy any wireless thermostat and it will work with my current receiver or do I need a new thermostat and receiver and have to piss about with wiring?

[@Professional_Youtube_Commenter]

yes you can they have 2 receivers make sure your replacement uses the same receiver as the one you got. You can easily re-pair them. If you can't find a thermostat without the receiver, you can just buy the kit and reinstall the wires in the new receiver.

[@blackmoresblood2489]

I'm replacing the same model. CM921. No matter how many times I press the buttons as you do, the unit will not go into the test transmit mode. Incidentally, a Honeywell video on here says press the left button, not the right one. Doesn't matter in my case though as neither option works for me!

[@LukeLewisme]

EXCELLENT..Though I prefer Openthern, as it takes away any of the risks associated with 230volt and DIYers.

[@brookybrook3725]

The led screen on my wireless thermostat has gone. I need to buy a new one and am interested to know if I need to replace the receiver on the boiler too, or will the new wireless thermostat work on the existing receiver?

[@phillipphan1394]

My existing Danfoss TP5000 only has COM and NO wiring. It is battery powered. To install your CM921 i will also need L and N. Can i spur that form adjacent Light switch or power socket?

[@raresizzle2935]

Great vid :) I'm wiring my stat into a Worcester boiler which has different terminals, can u make a video because I've been fighting with this for 2hours now and I'm shit with electrics :(

[@786qad]

Read the manual

[@SynapseGames]

Hi there. I am about to put a new Siemens rdj10rf receiver on my Boulter buderus boiler as the receiver has had it. Is it a case using existing wiring, disconnecting the old receiver and wiring it in to the new one?

[@mick.Walker]

was that also a timer !! i noticed it had date and program on it.

[@ianblaymire7741]

Hi good video, can also just use 1 - 5 core cable 0.75 heat resistant flex-saves running 2 x cables.

[@ultimatehandyman]

Ian Blaymire Personally I would do, but I am sure it said in the instructions to use two separate cables- perhaps you get interference if you use just one cable?

[@holmesway]

What setting do you leave the the boiler thermostat and timer to once the Honeywell remote is functioning?

[@alibee1978]

If I lose my thermostat as In the same one as this , do I need a while new kit or just the thermostat itself . Great video dude 👍🏻👌🏼

[@ultimatehandyman]

You can just buy the thermostat itself. When you get it, you just pair it with the old unit. Thanks for the comment 👍

[@hotsugar654]

Great video, very helpful, thanks. I am trying to connect my BDR91 from a heatline caprizplus. It has a single connection for Room thermostat labelled (RT) and another one for Frost protection (FP) apart from the live and neutral. As our boiler doesnt have 2 switching wires as in your video, it is confusing as to where to connect it on the BFR91 - do I have to use any jumper leads? Thanks

[@ultimatehandyman]

I'm not sure, sorry. This is the only wireless thermostat that I have installed, so far. Thanks for the comment

[@hotsugar654]

@@ultimatehandyman No problem, thank you for a quick response.

[@futurebil1267]

Thank you reconnected my wifi honeywell by viewing the last few minutes.

[@ultimatehandyman]

+Future Bil Thanks for the comment ;-)

[@708mrmike]

Sound vid and thanks, just a quick question, just fitting a Worcester 30i , am I ok to come strait off the fuse spare for the power to the receiver and just have the switching wire going to the boiler?......kind regards Mike.

[@ultimatehandyman]

Thanks Mike, yes that should be fine.Thanks for the comment.

[@kwasipoho]

A company called ventstar makes a model that works in multiple rooms Sith multiple receivers.

[@savagesi29]

Great vid - would this be classed as a volt free thermostat as it didn’t require additional power source? Looking to fit to my Ferroli which can only have a volt free receiver fitted. Thanks in advanced.

[@ultimatehandyman]

Yes, if I remember rightly it is zero volts (you just need the L and N connecting to power the unit). Thanks for the comment

[@rayc1503]

Volt free would have been wired in the same way.

[@fightingcockcoglan]

the two black switching cables ???,,,the block terimal with the loop in on my boiler are market 1 and 2,,,are they to be connected to a and b on stat yes,,,???,,,1 to a and 2 to b yes,,,???...

[@markanthony6778]

Hi helpful video thanks. I need to replace this exact stat with a smart stat. The only thing I am confused about is the switched wires, does it not matter which way they go round in the boiler or receiver? It didn't seem to matter in the video? Thanks

[@ultimatehandyman]

It does not matter with this boiler/receiver as the receiver is simply replacing a link wire in the boiler. When the receiver calls for heat, it closes a contact to make the circuit on the boiler.

[@markanthony6778]

@@ultimatehandyman thank you for your help.

[@mmack3286]

Hi I need your help. I have a combi boiler connected toa room thermostat programmer and when it was first installed t worked fine. But now it doesn't?

[@sharonbaillie9316]

freezing in here, this worked sweet as

[@ultimatehandyman]

Thanks for the comment ;-)

[@khanny2002]

Hi Mate, have you worked with a Worcester Bosch combi? is so, which are the switching terminals I need to use? I can see Ls LR Ns L N, which need to go into A & B