Atag IC36 & Hive Thermostat

[Ian_Rob]

I have been given a Hive Thermostat for Christmas and have been looking at how to connect it to our Atag IC36 Combi Boiler.

Though a 3-core cable runs from the boiler to the Honeywell CM907 thermostat, the SwL isn’t connected at the Honeywell. Not sure if it has come loose or was never connected?

From earlier postings I believe that I need to connect the existing L & N from the boiler to the L & N of the Hive and the SwL to the Heating On (Terminal 3 ) of the Hive. Is that correct?

As there is currently no earth connection, I am planning to replace the 3-core with a 4-core so that that I can earth the Hive. OK?

Thank you .

PS I have just looked at the Hive Receiver and though there is an Earth terminal it doesn’t actually connect to anything. Replacing the cable with a 4-core seems pointless.

 

[ianmcd]

Earth not required on the Hive

 

[Ian_Rob]

Finally got back onto wiring the receiver up this afternoon and despite there being 230 volts at the L & N pins there is no indicator light steady or flashing. I am beginning to think that the receiver is faulty??

 

[ianmcd]

yes sounds like you have a faulty unit, but when you replace it you will need to make sure that the boiler is wired for 240v switching, as you have only three cores this suggests that it is, then you need to make a link between L&1 on the hive backplate

 

[Ian_Rob]

I haven’t linked L & 1. I don’t suppose this would be causing the problem would it?

Thank you.

PS - It is a Combi boiler

 

[Deleted member 267285]

I haven’t linked L & 1. I don’t suppose this would be causing the problem would it?

Doubt it, as it should still power up from the L &N, just wouldn’t do any switching.

 

[Ian_Rob]

That’s what I thought. Thankyou.

 

[ianmcd]

did you use the new backplate ? or just the existing ?

 

[Ian_Rob]

did you use the new backplate ? or just the existing ?

The new one. Thinking that the problem may be a poor connection between the pins and the backplate connections, I jump wired them using crocodile clips from my volt meter probes but still no indicator light. The Hive was from Amazon so we have arranged a replacement that should arrive today.

 

[Ian_Rob]

PS. As a matter of interest, why is it necessary to link L & 1 when Terminal 1 is ‘ Hot Water Off’?

I would have thought that as the boiler is a Combi and the hot water under the control of the taps, that it wouldn’t be required??

 

[Deleted member 267285]

There’s a distinct difference between a single channel (usually for combi boilers) and 2/dual channel receivers. On the single channel ones they have volt free connections and links are required only if 240vac switching. Terminal 1 on these is common, not hot water off (dual channel).

 

[Ian_Rob]

Thanks CBW, the receiver is a single channel. I must have been looking at the dual channel diagram on Google.

 

[Ian_Rob]

The replacement Hive arrived but the single channel receiver still shows no indicator light.

It is wired as follows:
L - L
N - N
L - Terminal 1 (common)
SwL - Terminal 3.

There is 232 volts at the L & N.

Where am I going wrong..…?

 

[cross thread]

What reading do you get live to earth and neutral to earth

 

[Ian_Rob]

The cable from the boiler to single channel receiver is 3-core (Live, Neutral & Switched Live). No Earth.

PS. As soon as the receiver is attached to the backplate the boiler runs but no indicator light.

PPS. I have just wired one of the receivers independently to a mains socket and the indicator light glows. Have also checked the polarity at the boiler and it is correct.