Heat link e - Wiring setup help

[Barney626]

Hello,

I have recently moved house. My previous boiler had an external programmer box which was very easy to swap the wiring over to the heat link.

My new boiler is a worcester greenstar 28CDi Compact ErP with a built in comfort 2 RF receiver. Looking at the worcester instructional video the jumper between the red 'L' port and the demand 'LR' port must be removed for third party controllers. 

Then looking at the wiring diagram for the boiler, I believe I need to make 2x connections. The boiler LR port to the NO port on heatlink for the 'demand' wire. Then the boiler 'L' port directly to the heatlink 'C' port for common. 

I made the connections as described above then setup the thermostat & heatlink on the app:

Everything looked OK and connected up on the app. I set the thermostat to a high temperature to request heat but the boiler did not respond. I tried setting the old thermostat to a high temp to eliminate that but still no response from the boiler. 

Is there anything obvious I've overlooked which could cause this? 

Thanks

[AlexD]

Thanks for reaching out to us here @Barney626 and thank you for all the information. I would be happy to try and assist. 

Since you mentioned that neither the E version of the thermostat or the old thermostat worked after the change I would recomend you get in touch with the boiler manufacturer or/and an installer. A local one or a Nest Pro if any are available in your area. 

There are a few tests we can do with the thermostat to see if it is working as expected meanwhile. 

With the Nest app open on a mobile device, go next to the Heat Link. Select the heating controls and make sure the temperature is turned down, heating off. Turn up the temperature so the heating would be on and listen for a clicking noise from the Heat Link, then turn it down again and listen again for a clicking noise. A click on both occasions would indicate the internal relay is switching as expected. You can also press the button on the Heat Link once to bring up the status LED and again to engage the manual mode. A wavy LED symbol should come on and you should hear a click. Do the same to turn manual mode off.

Based on your description the wiring sounds correct as you seem to have the E version of the thermostat. C requires a live wire with high voltage and NO will have the wire that goes to the boiler for demand, call for heat. This is the wiring in most cases. 

It is possible that the boiler might need some setup changes, if it has a display where you can adjust them, wiring changes, or possibly not compatible with some thermostats. You would need to check these with the manufacturer and possibly an installer. 

[Barney626]

Hi, thanks for the reply.

To be clear, I've only ever had one nest thermostat which is this current heat link e. It worked flawlessly at my previous address but I'm now struggling to get it working at a new address with a different boiler. The boiler itself functions OK with its current 'dumb' rf thermostat. 

I've tried creating heating demand but did not hear any click sound from the heat link relay. I've also pressed the central button which showed a wavey green light for a few seconds but never made a click sound. 

Is there a way of confirming if the relay is OK? 

[Barney626]

 

These are some pictures of my setup attempt. For some reason was unable to upload them to the first post... 

[AlexD]

No worries, thanks for the pictures. On the Heat Link side, where I am able to advise, it seems to be correct. The call for heat wire is in NO and the live wire in C. 

On the boiler side, I am not specialized on them, but something to consider is that the L terminal on the left side may not actually be powered. If you are comfortable and have a multimeter on hand you could try and check the voltage. You could also perhaps check with the manufacturer or user manual. Perhaps that terminal requires live power and does not actually deliver power, but I could not say for sure if this is the case. But if that was the case it would make sense why the heating does not activate as even if the relay in the Heat Link moves and makes a contact, no power is traveling through the live wire from the boiler to the Heat Link and from the Heat Link to the call for heat terminal. 

[AlexD]

Hi, I wanted to check in. Do you need any further assistance? If so, make sure to let me know. 

[AlexD]

Hey there, I haven't heard from you in a while so I'll be locking this thread. If you have any new issues, updates or just a discussion topic, feel free to start a new thread in the community. Thanks, AlexD.