Fixing wiring for existing installation Vaillant Eco Tec 630 + Evohome due to faulty actuator

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Hello
I find myself in the unfortunate position of being unemployed at the moment and savings are depleting quickly. I have just started heating a couple of days ago, and I forgot that I noticed already when switching it off in April that the boiler was running continuously, which is not what I want given the lack of money supply.

System is:
  • Vaillant Eco Tec 630 from 2014
  • Vaillant Cylinder 180 (don't think the model is relevant but tell me if it actually is, likely some Unistor from 2014), with a TLSC thermostat to command the boiler + an electrical heating part in case there is an issue (that I used for the last 6 months when boiler was off for ~2.5 hours of water heating a day). TLSC seems to work fine as it clicks when I turned the temperatures lower or higher using the rotator.
  • 3 actuators:
    • (Shi__y) Danfoss HPA2 for the water heating
    • (Shi__y) Danfoss HPA2 for all radiators on 1st and 2nd floor (has been disconnected for a long time as it kept dying every other year)
    • Honeywell V4643H 1056 for ground floor (underfloor heating)
  • Evohome system
    • one BDR91 commanding the entire system to the boiler
    • rest is many radiator valves and multiple commands for underfloor heating
  • One Honeywell wiring box, with a separate main supply.
There is no issues I think with the Evohome system. Temperatures in the various rooms are where they are supposed to be, with valves being opened and closed normally as temperature varies. Also, the messages sent to the boiler as seen in the dedicated menu of the Evohome central command seem all correct. Only 2 bathrooms without valves are heating continuously (I have too many different rooms for 1 Evohome command)

However, even when the Evohome system sends no "run" message to the boiler, boiler is still running. The BDR91 relay light shows there is no issues neither. It is switching on continuous green when there is a "run" command or is switched off otherwise.

Everything used to work fine until (again! At least fifth time) one of this sh_tty Danfoss actuator microswitch died (resulting in boiler running continuously again as the death of the microswitch seems to result in sending a "run" signal to the boiler). I replaced the actuator like-for-like (after having moved a few times manually the valve, that does not seem to be particularly difficult to turn anyway), wiring it exactly the same and everything was fine again for a couple of weeks. Then, again, boiler was again running continuously. Thinking it could not be the Danfoss actuator as it was brand new (and they last usually ~2years), I de-wire the Honeywell actuator for the ground floor zone and force it open with the lever. Still, boiler is running continuously.

So, I'm thinking that I either "disconnected" the BDR91 relay as removing cables may have prevented it from sending signal to the boiler, or the same with the TLSC command for the cylinder, or that, again, the HPA2 has died after just a couple of weeks this time. In any case, I think I'm done with these actuators for the moment and want them disconnected, even if the boiler may consume a bit more gas to keep water warm in all zones (what it does anyway already for 1st and 2nd floor when any other zone was running). The additional consumption will for sure be less than having a boiler running continuously.

So, please, would anyone be kind enough to explain to me how to wire everything properly, excluding the actuators? Vaillant boiler has 2 large cables, each with blue/brown/green-yellow cables (maybe one for commanding heating and the other one for commanding water heating?), main to the Honeywell wiring box has the same blue/brown/green-yellow cables, as does the BDR91 and the TLSC thermostat. So, it is about how to connect everything together properly.

And if anyone is even kinder and can spend a few minutes explaining how these actuators are supposed to be wired as I have a spare HPA2 and may use it to leave the valve closed to the water cylinder if not needed. HPA2 has 4 wires blue/brown/grey/orange while the Honeywell V4643H 1056 has 5 wires blue/(light) brown/green-yellow/grey/orange.

In normal times I would call a plumber, but I cannot afford it unfortunately.

A great thank you in advance.

RRRR PPPP
 
Ok, first thing, do you have a Vaillant time switch? You say it worked fine, but wondering if the 24v link has been left in.
 
No Vaillant time switch. Never had one. Used to have a Salus RT500RFTX, but it was temoved when Evohome was fitted. Thanks
 
Seems to be getting a switch live from somewhere, but just confirm this by using the 2 i buttons (press at the same time) giving a status code - S.04 should show if it's continuing to fire up.
 
Yes, heating mode burner mode, code S.04. Boiler has been running for 3 hours continuously, with Evohome system off, BDR91 light off and water heater at minimum temperature (I turned it higher a couple of hours ago and heard the TLSC switching on, and then put it back at minimum and heard it switching off).
Temperature in the pipes has been at the target temperature for more than 2.5 hours. All radiators cold (except the 2 without valves in bathrooms) and underfloor heating is cold as well.
Thank you
 
Ok, so it's either the motorised valve micro switch or there's a link somewhere keeping it on, maybe even at the PCB
 
Please, how is everything supposed to be cabled if I drop the HPA2 completely? I think some cables may not be linked together anymore as I dropped the Honeywell actuator, as that may be the reason why the boiler is on despite receiving no signals. I would imagine that by default it is on, unless something tells it to be off?
Thank you
 
Please, how is everything supposed to be cabled if I drop the HPA2 completely?
Not entirely sure what you mean by this. Do you mean get rid altogether or just leave valve open and head off?
I think some cables may not be linked together anymore as I dropped the Honeywell actuator, as that may be the reason why the boiler is on despite receiving no signals. I would imagine that by default it is on, unless something tells it to be off?
Thank you
Go to each motorised valve power head and push on the manual lever, whichever is floppy is likely the failed one
 
Thank you.
So:
- HPA2 seems to be dead again indeed. Cannot see the lever coming back when I open manually.
- I just opened the BDR91, and it is cabled this way (cable to the wiring box)
* blue cable on N
* brown cable on L
* connector between second L and A
* green-yellow cable on B. I don't think this is earth, this cable is used to command I imagine.
 
however, in the wiring box, this green-yellow cable is connected to ... nothing. So, I would imagine the BDR91 is not commanding anything at the moment and that is the issue. It was connected to the rest through one wire of the Honeywell actuator I dropped in April as I thought it was defective.
Also, out of the 2 big cables coming from the boiler, one has also the green-yellow sub-cable not connected to anything anymore since I have dropped the Honeywell actuator. So, might be a second issue.
So, cabling is likely the issue as a whole, while actuators are likely all dead (the lever of the Honeywell actuator is lose as well).
Please, how should everything be cabled together in the wire box: the 2 big cables coming from the boiler (each with blue/brown/green-yellow), the main blue/brown/green-yellow big cable, the BDR91 blue/brown/green-yellow big cable (green-yellow likely being the command as it is plugged to B in the BDR91) and the water TLSC big cable (blue/brown/green-yellow)?
Thank you in advance.
 
- I just opened the BDR91, and it is cabled this way (cable to the wiring box)
* blue cable on N
* brown cable on L
* connector between second L and A
* green-yellow cable on B. I don't think this is earth, this cable is used to command I imagine.
All correct. Often green/yellow is incorrectly used
 
however, in the wiring box, this green-yellow cable is connected to ... nothing. So, I would imagine the BDR91 is not commanding anything at the moment and that is the issue. It was connected to the rest through one wire of the Honeywell actuator I dropped in April as I thought it was defective.
Also, out of the 2 big cables coming from the boiler, one has also the green-yellow sub-cable not connected to anything anymore since I have dropped the Honeywell actuator. So, might be a second issue.
So, cabling is likely the issue as a whole, while actuators are likely all dead (the lever of the Honeywell actuator is lose as well).
Please, how should everything be cabled together in the wire box: the 2 big cables coming from the boiler (each with blue/brown/green-yellow), the main blue/brown/green-yellow big cable, the BDR91 blue/brown/green-yellow big cable (green-yellow likely being the command as it is plugged to B in the BDR91) and the water TLSC big cable (blue/brown/green-yellow)?
Thank you in advance.
That will prove too difficult for me unfortunately. Maybe post some photos of the wiring center and someone may be able to assist. Or lookup how to wire an s-plan if you're any good at deciphering images
 
Thank you
Here are 3 pictures when 3, then 2 and finally only 1 actuators where in place (big black cables at the bottom left of the wiring box):
 

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Sorry, with 2 cables is the picture below.
The cable coming from the BDR91 is the right white one at the top left. As you can see, on the last photo of the previous post (8517), the green-yellow cable (in the ~middle connector, just before the gap) leads to nothing, while it was connected to a light brown cable coming from the Honeywell actuator before (picture 7528) and also to a brown cable from the additional HPA2 actuator that was first removed a couple of years ago (picture 3275).
 

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So your switch live from the BDR91 should go to the brown of the motorised valve, which in turn should drive the motor open, making the microswitch at the end, sending a switch live from the permanent grey live to orange. Similar operation from the cylinder thermostat and ufh.
 

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