Hello My name is Ian ~ I am not on the site constantly so please be patient whilst waiting for responses to you queries
Is it first or second generation?
2nd I believe. Model number T200377
OK just checking for you
Do you need any more info
OK the Honeywell T6360b is a conventional mains voltage thermostat working on 220-240V AC the Nest on the other hand is a low voltage unit. They are not interchangeable according to Nest. If you look at your installation guide step 2 it clearly states not for use on high voltage systems. Sorry, I guess you wont be able to use it with Your system ~ Ian
But the heat link is for that purpose. It takes the 220-240V and either wirelessly links to the thermostat or connects via a 12V cable
Give me more details about this heat link as whilst listed you do not give further details ie who makes it etc. Secondly why do you want to use an old thermostat with a modern intuitive control?
The Heat Link is the device provided by Nest. It's job is to take the mains power. It then links to the separate Wireless thermostat. I want to use this.new thermostat as I can't control temperatures in.the house at different times of the day. And it's meant to save me money as well.
Yeah got that, should have looked at the EU site not the American one ~ are you going to connect the two units via wireless or cable ?
I wanted to connect them by cable if possible. The thermostat is above a door under the stairs so I wanted to put the Heat Link behind inside and the Thermostat through the existing hole on the outside. I hope that makes sense.
OK these are the connections on the heat link ~ T1 & T2 go to the Nest thermostat. The heat link is wired Live & Neutral as listed and boiler common goes to 2 and call for heat goes to 3. So power in to Live and Neutral and switching between 2 & 3. Is that understood sofar? Now that is the Nest connections, is this where you are struggling or is it between the actual boiler and the heat link ?
Boiler and heat link. I have red in live. blue in neutral and yellow in 3 call for heat.
There is also a mention of hampering common and live.
...in the manual. By the way, I am a IT field service engineer just in case you wanted to know my level of knowledge in cabling etc.
...sorry. I should have said jumpering not hampering. Bloody predictive text.
OK that is good, look from what I see and stick with me here as you are my eyes, you have power going into the heat link so that is powered up but you don't have the switching on the central heating, I need to be able to look at the wiring to the boiler now as some boilers have switched 240v control whilst others are low voltage. In effect once you have the link between 2 & 3 on the heatlink and whatever the heat switching connectors on the boiler are you should be good to go. At the moment you only have one side of the switching connected.
I opened the control panel of the boiler a free days ago as a friend tired to help. The boiler for your reference is a Potterton Perform a 28. I will open boiler up again for you.
Boiler and control panel are now open.
OK I will look up the details but you will have to bear with me for a couple of hours as I have to go and collect the turkey from the butcher before he closes, will come back to you as soon as I am back ~ Ian
Ok. Thanks. Good luck with the Turkey.
Just before I go it its a 28i then the electrical connections for external control are terminals 1 & 2 which should have black wires at the other side, just link those two and see if this brings on the central heating. If so wait for me to come back and we can finish this off. Need you to get hold of a multimeter just in case you haven't got one ~ Ian
I will get a multimeter. Also this has got two black cables on 1 & 2 in the boiler.
I now have a multimeter.
Hi. Are you back yet.
Hi. Worried I may need power off and losing light.
OK here we go ~ Heat link terminal 2 goes to terminal on boiler (if it is a Potterton 18i)
start again #
Heat link terminal 2 goes to Boiler terminal 1 (if Potterton 18i) ~~~ Heat link terminal 3 goes to Boiler terminal 2 (if Potterton 18i) ~ Ian
This assumes only low voltage switching is being used.
OK hold on a mo will just check
I have used multimeter. Live red and neutral blue are 240. If I touch yellow it's at 100
You have two separate issues here, there is a 240v mains supply that powers the heat control. Then you have the temperature control also using two further wires that switch the boiler on using relays within the heat control, ie its just a switch not a power supply. So mains power into the Heat Link ie red, black and earth. Then wired Nest thermostat using T1 & T2 and finally connection between the boiler and heat link.as listed earlier Heat link 2 to boiler 1 and Heat Link 3 to boiler 2 ~ Ian
Is this where the jumper between common and live comes in to play
If I could power the heat link by the usb connection does that help?
Scrub the usb idea. It's for software updating purposes.
Look try and understand you have gone from a powered system to one that does not need to be ~ take a short piece of wire and with power off connect it between terminals 1 and 2 on the boiler external control terminals and switch the boiler power on, does the boiler heating work? ~ you have moved the question away fro
Look try and understand you have gone from a powered system to one that does not need to be ~ take a short piece of wire and with power off connect it between terminals 1 and 2 on the boiler external control terminals and switch the boiler power on, does the boiler heating work? ~ you have moved the question away from how do I connect a new Nest thermostat to a heat link system ~ to have I connected the boiler up correctly to the heat link system ~ think this way, boiler connections (power and thermal switching), heat link (power to run the heatlink, a switching part to control the boiler & thermostat information) Nest thermostat (thermal information to heat link)
It says in the installation potterton manual 1 is live. 2 is switched live. It also says to connect external controls to remove the link between 1 & 2
OK so with link between 1 & 2 in place is the heating working?
I haven't connected them yes as I am being cautious. Can I take a picture of the wires before i connect them together.
According to the Potterton manual that you refer to there should be a link between the external control connectors anyway when no external controls are connected that is terminals 1 & 2
How's it going have you managed to link them in a gleaned the results yet?
no. can't turn electric as it's dark now. If i switched switch off by boiler and lights are out that should be Ok?
OK tell you what come back to me tomorrow and we can continue, I'm here all day done the Christmas food shopping !! ~ Ian
ok. done it. Those two wires are connected. heating is now!!
Excellent job ~ now this is what you have to do when you can see in daylight, the Heat~Link unit uses a relay with its switching between terminals 2 & 3. Just remove the link and connect terminal 2 on the HL to 1 on the Boiler and terminal 3 on the HL to terminal 2 on the boiler and you are done - Would you now kindly rate my service to you by using the smiley faces below, once done you can come back tomorrow if you have further problems and I can help you out. There will be no further cost to you for any further questions asked once I am rated. Time you got warm and went home ~ Ian
At this time you are running the boiler on its own boiler thermostat, once you connect as above you will be running the Nest system
just to complicate things. the wires coming from the boiler on t1 and t2 are brown and green/yellow. this is not what i have on hl with the 3 red/blue/yellow wires
Dare I say it, welcome to my world. from experience the worst people to wire a house are electricians !!
so where do i go from here. i don't want to just leave this cables live at the thermostat
OK humour me, you have your boiler and a short distance away you have the HL and remotely you have the Nest Thermostat. Now if you have disconnected the positive and negative to the original Honeywell stat why have you got live wires at the thermostat that you have removed?
but how can i use the existing cables that are at the thermostat. I wanted to use the existing cables at the thermostat side as i am worried that the distance between the thermostat and HL might too far away.
.....or am i right in thinking that if I just use the cable from terminal 1 and 2 that is going to the switch with fuse in the airing cupboard with the boiler ( cut the cable and connect the hl) will that work. And should I disconnect all other cables that are now not linked to anything.
OK understood, in the Honeywell thermostat you have three wires connecting it, excluding the earth if fitted. They are live and neutral that if you like powers the thermostat and a separate switched live that would have switched the boiler on and off as required. So these wires should be disconnected from their original positions in the boiler. You can now take two wires, could I suggest two different coloured ones, they are unconnected at this point to anything. Take one and connect it to the HL T1 and then into the Nest thermostat to its T1, the other from T2 (HL) to T2 Nest. Fold the other one out of the way and tape it up both ends. You now have the thermostat digital connection from the Next to the control unit (HL) That is your temperature measurement in place. You now move from digital to old fashioned electrical systems. Power in to HL which you already have and then just the link 2~1 & 3~2 which controls the boiler ~ If you take as an example your computer, you have 240v coming in which is then transformed down to 5v or 12v as required. In this case, you have a boiler working on 240v, controlled by a HL working at both 240v and 12v and a thermostat purely on 12v hard wired or wireless as the case may be ~ Ian
have you gone home for the night?
Yes l have sorry. Will let you know how I get on tomorrow morning. Thanks for your advice today.
OK I will be around, could you kindly now rate my service so that I can close down this job, once done you can continue to ask further questions tomorrow free of charge ~ Ian
OK. This is what I have done so far this morning. I have used a 2 ply cable. Red and Blue. Connected terminal 1 on the boiler to connection number 2 on the HL (this is on the red cable) Connected terminal 2 on the boiler to connection number 3 on the HL.When I switch everything on I get nothing from the HL. No lights and unable to switch heating on with the override button on the HL. The boiler does have a light but heating will not switch on. I have now removed the cover of the fused connection unit next to the boiler. I have found that the yellow/green cable from the boiler in terminal 2 is connected to a connector which has the yellow cable going down stairs to the old thermostat. The brown cable from terminal 1 on the boiler is connected to a connector with a red cable coming from there to the thermostat. There is also a blue cable running from the fused box going to the thermostat.
Have you got power to the boiler and power to the HL use you multimeter to check
Lights on boiler. Which cables should I be testing. If I test between 2 and 3 I get no reading on the hl.
Sorry. I tested again. 120 between 2 and 3
There is 240 going into the boiler
And have you 240v going into the HL?
120 to hl
You should have 240v AC at the L & N connectors of the HL
The terminals 1 and 2 inside the boiler. ie the two black cables are at 110. Should I be connecting 1 probe of the multimeter on terminal 1 and 1 probe to terminal 2. I am also being lazy and just using the multimeter on the screw heads of the blocks. I did get*****on the live feed to the boiler.
Please keep to the script, by jumping around all you are doing is confusing yourself. I need to establish if you have got 240V connected to the power input terminals of the Boiler & HL. Terminals 1 & 2 have nothing to do with input power they are part of the control system and we will check that later when we have power confirmed to the boiler and HL
Ok. Now I am confused. The boiler input from mains is 240V. Where am I getting 240v for the hl from.
If you look at page 25 of the installation manual you will see that you require a 240V AC supply
So. Should I take a live and neutral from the fused junction box?
You need a 240V supply to the boiler and a 240v supply to the HL that is your first priority without these two mains supplies in place the system is not going to work.
by the way. I found this earlier and don't know if it helps.
Yes I have this information already together with the Nest installation manual. However once again you are jumping to another area of connection. I can link this that or the other into things but it is not me doing the job it is You, so since I cant see what your installation looks or consists of I can only ask you to do things systematically.
It is now all connected and working. Has been on for the last hour with no issues so far. Thanks for you additional help. Have a nice Christmas.