Honeywell LCD fail and repair

The LCD screen of my Honeywell CMS927 thermostat mostly stopped working.
See here how I fixed the display using a toaster.
(Also applies to the CM927 - the S indicates it was sold with the receiver. The 921 is the 1 day rather than 7 day version.)

The site for user manuals:

Inspiration from:

[ngorongok]

Its really useful and charitable of people to post these instructional videos and I'm sure this one would be very good. The problem is that the daft music, which is much too loud, completely distracts from the video and I can hardly hear the instructions. Also the music annoyingly increases and decreases in volume when the activity is fast forwarding. Having said this the gent has a quiet voice and this probably compounds the problem. Its soooo... helpful to have access to these videos and thank goodness people post them - just maybe in future it would be better to have the volume matched to the violume of the instructions. Anyway - Thank you "My Grandads Shed" good video.

[Blkmixer]

My mom's Honeywell screen had gone and before buying new I said let's look on YouTube. Followed your video and now were doing a dance around the kitchen. You saved us 90 quid! Many many thanks. Whoop whoop! I owe you a pint 🍻

[lucykenney]

Thank you Grandad's Shed, we had put up with extremely poor display for about three years and worked through your video - end result ...perfect display. Simple and clear instructions. Used a hairdryer on it's hottest setting instead of a toaster. Brilliant!!

[Allegratoys]

Sorry but you do have to turn the music off, it totally distracts from your message. Thanks for the video though

[colingibson]

I was all prepared to replace my Honeywell CM921 and was actually trawling the internet looking for them when I spotted your YouTube video. Got to say a big "THANK YOU"!! Followed it to the letter and now have a full screen again. Many thanks for a great video.

[BGSGBF]

Hats off, sir. Just baked the LCD of thermostat I've found after it's being in a barn for 10 years. The screen was dead grey, only some light in the corner. Three "toasting" circles (it was getting better with every time) and it's ready for use. Thank you!

[glyndavies]

I agree with ngorongok about the music and the audio quality - however, this video was super helpful to me in solving my problem with ghost characters on my CMS927 thermostat. I was planning to buy a new one - but the CMS927 is discontinued. Honeywell tell me it can't be repaired and recommend replacing with a Honeywell T4R thermostat (about £100) which then would need to be paired with with the installed receiver. This video (plus a bit of added ingenuity) has saved me all of that. My first attempt, using a toaster, failed but when I used a hair dryer and added a piece of shaved down ice lolly stick as square section packing (as at 7:04) it worked perfectly. I now have a fully functional thermostat with all digits and characters displaying correctly - and I've have had an enjoyable and rewarding afternoon. Many thanks!

[danram]

Tried this on my CM927 which had quite a bad case of failing display. Tried it a couple of times with a hairdryer and it ended up worse than it was originally. Decided I had nothing to lose so did it with a toaster for a couple of minutes and was amazed -- it's now perfect. So, the lesson I guess is, don't be afraid to give it a good toasting. Many thanks for the video.

[samwise]

I thought I was going to have to buy a replacement unit and this worked, just used a hairdryer instead of the toaster. Thank you so much for saving me £100!

[das]

just saw the 'I have another video with the background music removed here: ' link - that is most appreciated .

[yarmouthwolf]

heat gun and one bulldog clip. concentrated on heating clip (held with pliers) until screen looked like I may have killed it. worked a treat. saved me £200. for how long I don't know but see no reason it shouldn't last a good while 🤞. 1/2 hour pottering in my own grandads shed well spent. many thanks.

[davros]

Worked a treat using clothes pegs and hairdryer for 2 minutes. Thanks for posting...very helpful and saved £££'s getting a new controller.

[stevenward]

Great video. I managed to follow it and in my own experience I needed to hold over toaster until discolouration - about 2 mins. On the first attempt I didn't hold over toaster for long enough. Great video explanation, despite audio comments, and saved me £120. Many thanks !

[stoundingresults]

Fixed a nice LCD radio signal clock with your clue of applying heat. I used a hair drier. Thanks for posting.

[burgersnchips]

I don't fully understand how this worked but it did! Thanks!!

[dayangolanski]

Nice video, thanks god you posted a new one without this music. If you can speak louder it would be nice too. But thanks for your video! Helped a lot!

[fastabonjdebonj]

Thanks! Just copied you completely - worked a treat. You just saved me £100+. There's a pint for you in Portsmouth if you ever come this way.

[catherinecrowley]

Such a great help - thank you so much! I did exactly what you said and the problem is now solved. Amazing!

[marystevens]

It totally worked! used a hairdryer instead of a toaster.... thankyou!

[dirkdaems]

Great video, . I tried first another video which state to warm/heat the LCD for about 20s above a toaster. Repeated this several times without any improvements. Since the lcd didn't work i tried to ready heat for 2 to 3 min's also to the point the lcd slightly colored darker. And after the second long heat the display did work again !! Many Thanks .