Improve your central heating performance fit a digital room stat

[@jameslambert5803]

Bought and fitted one of these this weekend using this tutorial. In fact me and my wife bought our first home last year and been trying to do most of the work myself, I have used a number of your videos to help me so thank you very much and keep them coming.

[@dereton33]

Thanks James. Al.

[@tonywelch3076]

My mum has this same model. And i cant change any temperature or settings. Any one to help with a model number to a link guide pls

[@GeoffBerrett]

This gave me the confidence to do the same upgrade, which two days later seems to be working well. You’re a gent, thank you.

[@dereton33]

No problem.

[@tracylewis4385]

Morning can you let me know how to put the ignite flame on

[@Teddibere1]

ABSOLUTELY SUPERB Video!!! I could not believe I had EXACTLY the same manual Thermostat in place as this one and was changing it for the same Digital one as.here (both Honeywell). My Manual thermostat in the hall had stopped working. My good friend and I (both ladies) changed this ourselves, watching this video step by step on my IPad - lol. Procedures SO well and clearly explained. SUCCESS!! Thank you SO MUCH for this wonderful video.

[@dereton33]

Pleased you sorted it OK. Well done ladies, you are so much better at DIY then us men.

[@Ghostsandbutterflys]

.... A few weeks ago I plumbed in and fitted a new radiator - but it would only get luke warm and not heat up properly - I was about to call in a plumber but I found your video - and it showed me how to ballance the system and it immediately sorted the problem. Now, just last week my old 30+ year Honeywell room thermostat in the hallway stopped working (so no central heating for a week) - so I followed this video and replaced it for exactly the same one in your video following your instructions. Heating now working perfectly again. This is now the second time lately that your videos have got me out of trouble - and saved me having to call in (and pay) a plumber / electrician ..... Thank you so much 👍👍👍 Keep up the good work - saved me a few bob .... small donation sent 👍👍

[@dereton33]

Thanks very much, the donation is much appreciated.

[@rambo884]

Legend is a much overused word but this geezer is one. I am a DIY disaster but he made this easy and i am now basking in my glory and have some browny points with the wife! Keep up the good work mate.

[@dereton33]

No problem Kevin.

[@leonbryce8384]

Great video, but as an electrician I do not advise just cutting the earth wire off, sleeve it and pop a wago on. It makes it easier for testing purposes not only that when not connected together you are unable to obtain r1 r2 readings which then can become costly on the customer as it’s not always easy to find 👍🏿

[@dereton33]

Thanks 😀

[@benbradley2331]

Brilliant help mate. I had a old bio.metric British gas stat. Plumb shop suggested Drayton turn dial stat. Fitted it. Wouldn't even tell boiler to come in... Reason. Has relay that needs 240v in my red wire i only get 190v. Dont know why. But i went out and bought this honeywell u have. Works a treat. U saved my day. So thank you !

[@dereton33]

No problem 👍

[@Robby334]

After reading the instruction book my mate said let's look at youtube - found this great man helped us enormously thanks so much - following your clips was easier than the instructions.

[@dereton33]

That`s great .

[@Olivarus238]

I know that this is an old video, but it's nowhere near as old as my Honeywell thermostat. It dates back to 1991 and pre-dates the one that you replaced in the video. So I have just replaced it with DT90E, even though that must be at least 4 years old by now. Thank you for the "If you've got red, yellow, blue and earth" section, because that's exactly what I have. Using the red and yellow stopped me using the blue! It's perfect and working well. Great video!

[@dereton33]

Thanks John.

[@ILYWAMBFH]

Hello. Thanks very much for your informative video. My central heating failed to fire at the weekend. Water was okay but the heating wouldn't come on when I turned the thermostat up or put the heating on constant. I ordered the same Thermostat control in the video and fitted it last night using your wiring instructions for the yellow and red wires. Bingo! works fine. So Thanks. Can't help thinking that your very calming voice is also of great benefit to anyone watching these films as most like me will be in some state of panic at the thought of an impending night of minus seven degrees with no heating. Your somewhat soothing manor acts almost as therapy for anyone in such a situation. So much so that the next time I get stressed out I might watch one of your films just for the calming effects despite not having any central heating problem. Cheers

[@dereton33]

Thanks for those kind comments Richard, I am one of those people who rarely gets stressed about anything. Just lucky I guess.

[@SecretOfMonkeyIsland784]

Just spent 3 days in my house at 11c (internal house temp) when my boiler failed at it was -2c out, so i can sympathise how hard that would have been. Winter coat, 2x t-shirts, hoodie, thermal socks and blanket and still cold.

[@jasonedwards7831]

Thank you for this, will make my home much more comfortable. Got fed up with getting up and down to adjust the temperature with the 5 degree difference. 👍👍👍👍

[@dereton33]

Enjoy!

[@1977fuzzedup]

Hi, followed your video and swapped over my old bi metallic thermostat to this one and already the house feels warmer and a more constant temperature. Cheers for the video and keep up the good work :)

[@dereton33]

Thanks.

[@pacman4568]

Good video, I have been told the yellow wire and the restrictor has a reduced power connection to the boiler. I was warned should you connect the 240v directly to the boiler you can kill the circuit board in the boiler.

[@Teddibere1]

To Fred Turner - I had the same problem as you were having with your OLD thermostat. Alan is MARVELLOUS!!

[@dereton33]

Ha ha thanks.

[@happyharry7331]

very accurate thermostat the only downside is it continues to monitor the room temperature even when the heating is off with a loud click when it senses the temperature is low, not a problem if you are in a large house and are remote from the thermostat. We are in a small bungalow and the click is loud I basically turn the thermostat to the frost setting and that stops it. and turn it on again in the morning. Checked this out on several websites and other people also moaning about the loud click

[@dereton33]

Thanks for the info.

[@tdc_2021]

Agree. The constant loud clicking is outrageous. Looking to change mine

[@antlondon2]

Been subscribed for a while. Hadn't seen this video. Wanted to change thermostat today. Found this video. Bought the same one as still available for £36.99. Ten minute job to switch over as needed new holes drilling. Also had red, blue, yellow, earth wires. Followed your advice and worked like a dream. Cheers. 👍

[@dereton33]

Glad I could help

[@fixityourself7258]

Excellent Advice! Did this upgrade a couple of years ago following this video, before i was a subscriber and it's saved me a fortune and maintains the room temperature so much better. Would recommend this to anyone still using the old analogue thermostats. Great Channel, many thanks.

[@dereton33]

Thanks for sharing!

[@andycarter9845]

Did the exact same switch you outlined here, very smooth, thanks. House much more comfortable now with the new stat.

[@dereton33]

Nice work!

[@andybell8452]

Al - thanks very much for doing this video - it was exactly what I wanted to do, but had 4 wires originally - needing to go down to 2. All working nicely, thanks to you!

[@dereton33]

Excellent!

[@PuckyStan]

Thanks for this. Had one of the manual thermostats. All it did was turn the boiler on or off. With your help changed it over myself. Working properly now. Cheers

[@dereton33]

No problem Anthony

[@philmanning2549]

just installed one took 10 mins,easy to use too,only prob is although its set to 23c actual room temp is 24c,boiler comes on at 24c even though thermost is set at 23c,.my flat seems warmer now than did before.

[@marksutton6428]

Really useful video. Followed the tips and had my new digital thermostat up and running in 20 mins and boiler is now providing heat as required. Many thanks

[@dereton33]

No problem Mark.

[@petermcardle2199]

Just wanted to let you know that I had a very old thermostat, older than the one in your video, so I bought the model you used. A friend came to fit it but, even though he's an electrician he didn't connect it correctly. He works on industrial systems so wasn't familiar with this type of job really. I showed him your video and two minutes later it's up and running. Thanks.

[@dereton33]

No problem.

[@dermotkelly6946]

Hi Al , I have just changed to a DT90E today , from the old thermostat which was identical to your old room stat , at the moment me and the Mrs are just staring at it 🤔, all this technology 😳, but something is happening and the rads are coming on , will have to get one of the kids around for a crash course . Thank you very much for this video things worked exactly as you explained . Many thanks , Dermot Kelly .

[@dereton33]

No problem Dermot.

[@Teddibere1]

I would like to add a personal THANK YOU to Alan. Wish I had YOU at home - lol. Xx

[@dereton33]

That`s really nice thanks Teddy burr, I keep telling Jan how lucky she is, but that results in a clip round the ear. H ha (only joking)

[@davie78sti]

Great vid,just changed the ancient mechanical 4+1 split wire in my flat to the same 2 wire digi style like this though the one I got also had an earth connection so i wired that in as well,within an hour can see the difference in accuracy with boiler on/off times 👍

[@danboulton2128]

Fantastic and really helpful. I bought one of these for our new bungalow but being colourblind, my wife had to help me make sure the correct colour wires went where they come out of! :-) Thanks again.

[@dereton33]

Glad I could help!

[@ianto218]

Al - Thanks for a very informative video. Our electrician followed the manufacturers wiring diagram, including using the neutral wire causing the 3 amp fuse in our boiler switch to continually blow. Once the neutral wire was disconnected, the device worked without issue. Your helpful video helped immensely in identifying the problem.

[@dereton33]

+ianto218 . That`s great, pleased to have been of some help.

[@neilsluman8267]

Thanks for this. Was a little anxious about whether this would be complicated but you've shown there's nothing to worry about.

[@dereton33]

No problem Neil.

[@MrDaveHutton]

Really good video Big Al. Explained in laymen's terms and re-assured me that the neutral and earth wires in my existing EHE 0200155 are not needed. Good stuff 👍

[@dereton33]

No problem.

[@MrDaveHutton]

@@dereton33 I have a separate box that does all the timings. I can set up to three a day. Will there be a conflict with the ability to do the same with this one on the ECO button? I've been trying to get one after I saw your video. Seems they are in very short supply, unless I pay a silly price. Screwfix do them for £34.95, Toolstation £118.98, City Plumbing £108.60 and all prices in between. No stock in Screwfix anywhere near me in South Wales. The cheapest on Amazon is £62. I'll get there, eventually!

[@tomsmith5456]

Thanks Al , just had one fitted , it’s working a treat , big improvement on the old bi metal one .

[@dereton33]

I found the same.

[@darkbyte2005]

Hello del, i found this ole video you done and it gave me all the confidence to install. It was very easy to do mine had the 3 wires. The neutral is actually for the resistor/ Heat Anticipator to make the stat work more accurately as you say within 2 deg rather that yours which is 5 deg. But i see the digital ones know work within 1 deg of accuracy without need for neutral . Once again big thanks to you taking the time making these videos. nice one.

[@dereton33]

Nice work!

[@davidfarquhar3917]

Very helpful video. Bought one of these and fitted it today. Glad you mentioned the different wiring colours as I had the alternative version and your guide helped a lot

[@dereton33]

No problem David.

[@8acv8]

Thank you for the useful comment for the case when there are 4 wires (red, blue, yellow and earth). Only connecting RED in A and YELLOW in B (leaving the other 2 out isolated) works perfectly.

[@dereton33]

Glad it helped

[@GojuRyu1976]

What of you have a brown, blue and earth wire??

[@amana1480]

Good idea. I do find the front comes off this thermostat a bit too easily though. I have the same thermostat.

[@nigelmartin2248]

A great explanation, nice and simple, excellent! Quick question, in my current unit ( exactly the same as yours) Th current wires are as follows: EARTH x 2 wires, Number 2 slot BLUE wire, Number 3 BLACK wire, Number 1 slot BROWN wire..... Would I be right in the new unit wiring to be: LIVE, into A slot- BROWN, NUTURAL into B slot- BLACK, or BLUE? Any advice guidance would be greatly appreciated.! Again, thanks so much a great source of no nonsense example.

[@dereton33]

Check that neutral with a tester first sometimes the black can be switched mains.

[@nigelmartin2248]

@@dereton33 Many thanks have sorted!

[@andybeeley]

Thanks Alan for doing the video, just replaced my old Satchwell thermostat with the Honeywell DT90E, made easy and straight forward.

[@dereton33]

No problem

[@gratisprince4147]

Thank you Alan for your simple and concise explanation. Allowed me to replace my parents faulty thermostat for this much more reactive product with confidence.

[@dereton33]

No problem Gratis.

[@trevorhawk2000]

Just replaced mine to this model, quite straightforward after watching this video, thanks.

[@dereton33]

No problem.

[@Tupperz96]

love these videos :) I'm an HVAC apprentice, and for some reason I just find your videos great to watch.

[@michaelbowron3884]

Thanks for this I was really struggling to get this to work until I saw your video and you showed how to lose the neutral as I had 3 wire system it was great especially as this wasn't explained in manufacturers instructions

[@dereton33]

You're welcome!

[@theCybershot123]

Hi nice little video . in the old days the electricians used red/black plus earth cable to wire a stat exactly as you have . Now they have to use twin brown cable I would have put a bit of brown or red tape on the black cable just to identify it being a live cable .

[@TheDoosh79]

+theCybershot123 If he was going to put any tape on then it would be blue, as black used to be neutral, red is the live.

[@theCybershot123]

+Matt Jarrett As I stated the black cable is not a neutral wire but a live conductor so should be identified correctly brown/red

[@Iveraghboy]

Cheers Al good job, did you ever sort out the Seagull problem ?

[@dereton33]

Yes I just befriended one and fed it . That seagull now keeps all the others away.

[@executionsquad9998]

Many thanks Al. I have been watching all your videos for the the last few years and I think your fantastic person to give all that free advice and info! I have learnt a lot from you. Thank you very much. I have Vaiilant ecoTec plus 418 boiler and Drayton lifestyle controller underneath . My stat is Drayton as well, does that mean I have to get Drayton digital stat?

[@dereton33]

No, it just means it will be a direct replacement without having to re-drill fixing holes or being a different size and so leaving marks on the wall. You can get any make though that you like.

[@johnnystromberg]

Thank you! By pure chance I had bought the same stat as you fitted! Perfect instructions... Very grateful

[@dereton33]

You're welcome!

[@herbiee22]

Excellent. Thank you. Short and accurate. Sorted out my wiring problem with 4 wires going to 2....brilliant.

[@dereton33]

You're welcome!

[@RogerWallis-xn3mw]

Excellent video, extremely useful and clear. Just wondered how you moved the cable to the new hole without it disappearing into the wall as I have the same problem?

[@dereton33]

My wall was excessable in the cupboard the other side of the stat..

[@RogerWallis-xn3mw]

@@dereton33 Thanks for getting back to me, much appreciated. cheers

[@terryd229]

Great video although I already had a good idea how to install I still found watching this video helped me. Excellent video well worth checking out before you do the swap.

[@DavidLewis-ev8sg]

Very helpful video thanks very much fitted new digital Honeywell DT 90 eco from my local Toolstation

[@dereton33]

No problem David.

[@SimplyRevolting]

Never lived in a place with central heating ever before, just moved in; how to set helped, thank you!

[@dereton33]

You are so welcome!

[@michaelbaines2383]

Great vid, exactly what I need to do in my new property. How does this talk to the boiler? Assume it needs some sort of receiver in the boiler?

[@dereton33]

It just replaces your old wall stat.

[@Andrew-ry7iw]

Brilliant! Way better than my old thermostat

[@gcmarcal]

Thanks mate! Exactly what I need, mine started playing up and today did not let the boiler ignite. Luckily I found out that the boiler is fine and is just a 10 min repair with your fantastic tutorial

[@dereton33]

No problem.

[@whopaimon5407]

You have helped me a alot doing my own little jobs around the home, thanks Alan

[@dereton33]

No problem.

[@lambal8554]

Greatings from Holland your vid is great and have to say it gives people a bit of confidence to operate it and check your vid for info if they forget how to use it properly. Thanks

[@dereton33]

Thanks Iam.

[@MoreChannelNoise]

weren't the wires different coloured in Holland

[@4_am]

Thanks for this, i was struggling finding the unit name for my thermostat! DT90E cheers for that.

[@dereton33]

No problem 👍

[@derekrowlands1189]

Watched your excellent video very informative and very easy to follow, the only problem is I am confused with the instructions, (nothing new there) can you tell me in simple terms how to set a maximum temperature of say 20 degrees, many thanks.

[@dereton33]

Just set the temperature by the push button on the front, that would be the maximum temperture.

[@roybatty2030]

Another great vid, thanks. I’m changing mine tomorrow!

[@dereton33]

Thanks Rus, good luck with it.

[@markellis7819]

The only problem with those is that you only have one temperature setting, so have to change it yourself if you want different temperatures at different times of the day. The Danfoss TP5000 gives you 6 different time periods, with any temperature that you want at those time changes, at half degree increments.

[@dereton33]

Thanks Mark.

[@mattsedge3525]

Thanks for a great video, super clear and very detailed but explained in a very practical way, It was perfect for me as I changed the same old thermostat to the new one fitted in the video so it was word for word perfect! Thanks' again brilliant..... :)

[@dereton33]

You're very welcome!

[@markpulling12]

Hi firstly thankyou for a great video,ive just ordered a dt90e to replace the exact same bimetalic thermostat, im looking at my wires I have red live ,blue neutral and green earth all currently connected to the old stat,im confused because people seem to say you only connect two wires live and switched live ? what is switched live, you say do away with neutral and earth so do I JUST connect one wire the red live ? thankyou very much mark

[@yoya4766]

My cable only has a black and a green/yellow wire. There is NO red or blue wire. I'm not sure it's even function, as the black wasn't properly connected to the live slot. It is very old wiring (before 1980). How do I wire a new digital one? I believe the cable is a 6241y.

[@dereton33]

Best to get an electrician to check what you have as it is so old.

[@SamAmiri]

Cheers mate, had no clue had to deal with an analogue one but you got me going.

[@dereton33]

No problem.

[@brianp798]

I have also realised that when the thermostat is calling for heat(flame symbol ) the boiler switches off, and vice versa. I think the yellow and red need swapping round?

[@TheStratCat]

Hi, firstly thanks for this useful video. I have one of these fitted as per your instructions and it seems to work ok. However, as a couple of people have mentioned, it calls for heat when the timer/programmer is off and the room cools. Is that a 'feature' of this model? If so can I assume it's basically a battery operated on off switch governed by the temperature and not affected by the timer/programmer.

[@dereton33]

Yes.

[@davidyelee]

Your video is my only reference and guide. I thank you, once again.

[@dereton33]

Glad to help!

[@radumateescu5035]

I have the same problem, but i have different thermostat is Honeywell HCW80 but looks the same almost. Do you think will work to change with the digital Honeywell one. Thank you. Great video!!

[@vincetaylor944]

Hi thanks for your informative videos. But it’s gone wrong for me this time. I followed your replacement Honeywell room stat video. Apparently I have a High voltage system, so I’ve blown the fuse in the boiler. There was no mention of High/Low voltage systems in your video ?

[@dereton33]

That video is a bit old now. So if you are unsure about the wiring do consult an electrician. This wiring I showed was for a high mains voltage system.

[@vincetaylor944]

Thanks for reply Al, really appreciated it. I’m currently trying to source a stat that is suitable, but not having much luck so far. I’ve had to replace the 3amp fuse to my boiler and put the old stat back for now. But the good news is everything is working 👍

[@davidrolfe1996]

What is the basic difference please between this thermostat and the Honeywell DT2 (THR840DEU)? Thanks!

[@dereton33]

Sorry I dont know.

[@mtismee]

Nice and easy to follow No waffle ..... Thanks malc

[@dereton33]

No problem.

[@Iveraghboy]

Thanks Al this is my next DIY job .

[@dereton33]

No problem 👍

[@chadders71]

Hi, My wires are confusing me. I have Brown, Black, White (with some blue tubing on it) and the earth. Its a combi boiler and I have bought the Honeywell THR840DUK digital thermostat. I am assuming I connect Brown to (A) and Black to (B) and then tape up Blue and Earth. Is that right?

[@dereton33]

Yes, but you can always check it is the right way round with a test meter.

[@fevkin]

Thank you very much for that. Can you explain the on/off button on the thermostat. I've been pressing it off when I've felt the room's hotter than I want and pressing again when I want it warmer but I'm really not sure this is it's purpose

[@dereton33]

It is the on or off override.

[@rastageordie7338]

Hi Alan can you confirm live red goes to A /yellow with red sleeve goes to B/ and I have put blue neutral on a wago earth is connected to back box thanks

[@dereton33]

Yes it does, but If it was wrong your trip would just click out, so do not worry to much if your heating wiring is different. I usually suggest a test meter to check.

[@rastageordie7338]

@@dereton33 thanks for getting back to me mate appreciate that 👍👍

[@fredturner6535]

thanks very much for your video Alan have just changed mine from a 3 wire 2 wire was a bit nervous turn it back on but all went well think I had a fault with the old one not calling for heating keep the videos coming much appreciated

[@dereton33]

Will do Fred .

[@666pawel]

CLK Products Hi. Was it 4 cables at your? I have the same, so what cables did you use? Thanks.

[@justa1098]

I’m about to replace mine. It has 3 wires, do I only need 2 now then?

[@yetiibob8407]

Many thanks, just replaced mine and took 15mins! Really clear and precise. 😊

[@dereton33]

You're welcome!

[@mikebravo7732]

I have a blue, yellow & red wire in my current thermostat, to confirm I put red in A and yellow in B, then cap off blue?

[@dereton33]

Yes the blue is not required.

[@emrankhanlearnwithme4474]

Im thinking of buying this to replace my inaccurate analog room stat but this gets a lot of bad reviews for the clicking noise, did this irritate you?

[@dereton33]

It is a problem yes.

[@stud81]

Hi mate very good information from this video, I have just moved into a new house and renovating, looking to change my old yellow room stat to a modern digital one. My old room thermostat is a potterton prt100 and wanting to upgrade to the Honeywell DT4 room thermostat, my current stat has old wiring with red in terminal 1 yellow in 2 and blue in 3, do you know if the DT4 Will be compatible? Thanks.

[@dereton33]

Yes should be fine.

[@stud81]

@@dereton33 fitted the DT4 today looks a lot better than the old room stat, only issue is that when turning heating on and room reaches temperature the thermostat clicks but doesn't switch the heating/ combi off .

[@T120Mitch]

thank you, mine had the 4 wires and I was able to swap it with your advice.

[@dereton33]

Excellent!

[@26vignesh]

I have a brown and black wire and I am from Netherlands do they also go to A and B?

[@dereton33]

Best check with a multimeter first, it may be different to the UK.

[@adrianomartorana1616]

That's an excellent video, clearly explained and the the digital one would be perfect. However, I have an older Honeywell T1460 and it has three wires. A blue (N?), a Red (L?) and a yellow - there's also an earth not used. Can I still use the one on your link?

[@dereton33]

Yes it is still fine to use.

[@mojooev7785]

Can u replace my old Thermostat control with 3 wires with Honeywell Home Digital Room Thermostat DT90E! But my old one is not Honeywell brand?

[@dereton33]

Yes.

[@markbsac]

ive got a red wire and a blue wire on my old honeywell stat...so im assumeing the blue wire goes where your black wire has gone...i also have an earth connected

[@dereton33]

Yes but if unsure check with an electrician.

[@allanellis3768]

Thanks Alan for the advice just changed my thermostat EASY!

[@dereton33]

No problem Allen.

[@paimei26]

@@dereton33 did u switch the electricty off before changing ?

[@andersonec1]

If you,re still out there how do you undo the second cover? The first one which uncovers the batteries is easy but the second is made by the secret service.

[@dereton33]

Cant remember now, I changed that stat some time ago for a hive. Sure it just pulls upwards and off, do check there is not a securing screw on the bottom cover.

[@vincetaylor944]

There’s a little slot at the bottom to put a small flat blade screwdriver in .

[@DrBroncanuus]

hi Derek, I'm replacing my glow warm 24 hxi boiler with a Viessmann , but can you recommend a hot water cyclinder which is old and sits directly under the boiler in bedroom ?

[@dereton33]

I like Telford and RM.

[@DrBroncanuus]

thanks Derek, but is my system vented or unvented ?..i have cold water tank in loft plus small tank for central heating @@dereton33

[@dereton33]

Vented, what is called an F and E system.

[@DrBroncanuus]

Thanks alot Derek...will choose a hot water cyclinder today @@dereton33

[@1993jakeyboy]

Would the electric to the house need to be turned off or just the heating system?

[@dereton33]

To be safe turn off the house.

[@brianp798]

Hello I have installed this today, I had a red, blue and yellow wire. I have connected red to A and yellow to C. It doesn't seem to be working- the boiler comes on regardless of what I set the thermostat to? Thanks Brian

[@SazzyNoodles]

Hiya! I’m gonna sound mad for asking but what does the eco actually do? My boiler keeps turning itself on on its own and I don’t have a timer but have this exact thermostat and I don’t even want the heating on. Thanks!

[@dereton33]

The idea is to keep it ticking over so it does not have to heat from cold.

[@SazzyNoodles]

@@dereton33 thank you! How many hours would you advice eco being on for helping cut the gas bill?

[@wujekdobrarada.9437]

Hi. I have a black and a brown wire. How do I connect these colors? Thanks for the instruction.

[@dereton33]

Use a tester to se which is the switched live.

[@SeymourJohnson-ri5xt]

Hi. Hope you can help, as I have a 4 wire set up from my old Honeywell mechanical :- Brown is L, Blue is N, Grey is C , and yellow/green is E, so how does this wire into the Honeywell DT90E thermostat ??????,thanks in advance from a novice

[@dereton33]

Have replied via e-mail.

[@djj6810]

had one fitted today went from 3 wire to 2 wire, told the guy fitting it a gas safe guy and he still connects up 3 wire blows the fuse to programmer, didnt have 5amp so fitted 13amp and agreed was 2 wire.

[@dereton33]

Gas unsafe that engineer.

[@DjGiluk]

Do the same principles apply when fitting a programmer thermostat? Got my eye on one and wiring all looks the same as it’s a wired version

[@dereton33]

Good advice.

[@edwinflynn9744]

Help, its not working. Hi I have just changed over my old Honeywell two wired, mercury type thermostat controller to a DT90A controller. My wires are all white no red or black any color. I place what was connected to the thermostats red to terminal A and the other wire to terminal B. When I attempt to turn my gas heater on with the new controller it just does not work. Given both my wires are the same color, how to test which is the live and which is the neutral Please?

[@dereton33]

You will need a test meter to find out.

[@executionsquad9998]

thanks Al. Also the Drayton lifestyle controller i have which is underneath boiler ,is the wiring for that striaght forward like the stat on this video. as my one has only one programmable setting for example i could set 2 times a day for only hot water and not central heating. i was thinking of replacing that with more programmable one.

[@dereton33]

Should be the same, but to make sure, just check the forums or contact Drayton.

[@davelinkson1]

Thanks Al I've had one of these fitted recently by an electrician as he was doing a rewire on my place, but so far it seems unresponsive as it doesn't turn on and off at set temps and doesn't show icon when boiler fires, think I'm going to have to check it's wired right and get my volt tester on it..

[@dereton33]

Yes check it out.

[@davelinkson1]

@@dereton33 it's working now Al, I found blue neutral in B and yellow in C, so I done away with blue and moved yellow to B and now clicking on and off and boiler firing as required. A newly qualified electrician fitted it initially. 🙄

[@Dan-mf8jf]

hey Al, love your videos. I have a Worcester greenstar combi boiler, I have a very old fashioned myson analogue thermostat connected to it, looks like it's been there since the 70s/80s. I have had a look to see what wires it has. it has blue wire connected at the top, red wire connected at the bottom and a bare wire connected in the middle. there is a loose yellow wire not connected to anything. so can you just confirm which wires I need to connect to this new unit? is it red in the A terminal and the yellow that is not connected to anything in the B terminal? and the blue and bare wire safely tucked away.

[@dereton33]

Assuming the blue is the neutral then yes.

[@Dan-mf8jf]

dereton33 so connected the red and yellow, wouldn't fire the boiler. wasn't brave enough to try another wire, so got a qualified electrician out, better safe than sorry. after he checked the wiring, turned out it was the blue wire that was the live switch. glad someone professional did it for me. Thanks for you help Al.

[@perebrine]

Hi just a quick question. I removed the cover on my existing one & have 3 wires BLUE, RED & a YELLOW wire which has a Brown sheath covering it. The RED goes to "L". The BLUE to "N" The YELLOW with a Brown sheath goes to "Call". Is it the Yellow one I need? I'm quite happy to call an electrician & will understand if you're not comfortable give advice on here.

[@dereton33]

The yellow is normally the call, but do call an electrician if you are unsure. Some wiring configurations are different, to how they should be. You can check if it is right if you have a multimeter.

[@perebrine]

@@dereton33 Thanks for this, so it is the Yellow wire going to "CALL" the one I need

[@baronianmcclure8865]

I have very old wiring, three wires 1 black and 2 red? any help would be fantastic.

[@dereton33]

Best to check with a electrician old wiring can be tough to get right.