Replace Potterton EP2002 with Hive active heating

Can anyone help me, I want to replace my faulty Potterton EP2002 with the Hive active heating package (receiver, thermostat & hub). Can anyone please confirm or advise me before I start that I've got this right.
The terminals in the EP2002 are a like for like swap with the Hive receiver, ie: N/N, L/L, 1/1, 3/3, 4/4. Terminal 2 is not being used and also to disconnect the link between L & 5 in the EP2002, please see pics below.
Also that I must disconnect the room stat from the wiring but join together the room stat live with the room stat switch line in the junction box which is located in my airing cupboard. I am not sure what to do with the two cables that are now left, the white cable which goes to 3way motorised valve & the red cable which goes to EP2002 or soon to be fitted Hive receiver terminal 4).
Any advise would be much appreciated. For extra information the boiler is a Worcester Greenstar 24Ri.
I also noted that the person who originally wired the room stat used the bare copper wire in the T&E for a neutral and put earth sleeving on it just to confuse everybody.

I think ive just had a senior moment. Connecting together the room stat live & switch line does nothing so i think it must be the white & the red cables that join together? I really do need help.

You have pretty much worked it out. Terminals N, L, 1, 3, 4, are a straight swap from EP2002 to Hive (Dual channel version). Terminal 5 of the EP2002 is a link that the Hive already has made internally so doesn't need this connection, and terminal 2 won't be used, as it's not used now. The wires in the EP earth terminal need to go to the Hive earth tether to maintain continuity.

The existing room thermostat needs to be taken out of service by linking its live (L) and switched live (SL) wires together to prevent it interfering with the operation of the Hive and to complete the circuit. You don't give the make or model, but looking at your photo below, that would be terminals L and 3. There should be a diagram on it somewhere that will confirm. Very bad that the earth wire has been used as for neutral!


By far the best way to decommission the room thermostat (and get rid of the dodgy N) is to trace the cable from the thermostat back to its origin (probably the at the wiring centre) and note where the L and SL are connected. Then disconnect and remove the entire thermostat cable and insert a link to join together the two terminals that the L and SL have just been removed from.

Alternatively, if you don't mind leaving the thermostat in place, put both the thermostat L and SL wires in the L terminal.

Or, simply leave the original thermostat in place and put it on its maximum setting. This is not ideal in case someone inadvertently adjusts it, and if it's battery operated (don't think yours is though) you will need to maintain the batteries.

No need to change anything else or access the boiler terminals.

Cheers Stem, many thanks for your quick reply and advice on the Hive heating installation. I will be attempting to install the Hive active heating tomorrow so fingers crossed but I do feel more confident now. I will let you know how it goes.

Thanks for your help Stem, the Hive heating is now installed and up and running with no problems. Registering it on the app was more of a problem than installing it.

I’ve just joined today and started looking into the ep2002 on here to replace it. I was just wondering why terminal 2 isn’t used as it looks like it turns off the CH?

Freespirittime said:

I’ve just joined today and started looking into the ep2002 on here to replace it. I was just wondering why terminal 2 isn’t used as it looks like it turns off the CH?

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you would be better starting your own thread, CH off is very seldom used on any domestic system

Freespirittime said:

I’ve just joined today and started looking into the ep2002 on here to replace it. I was just wondering why terminal 2 isn’t used as it looks like it turns off the CH?

Click to expand...

Terminal 2 is only really used with motor on, motor off zones valves. Very uncommon these days.

Thanks Ian, yes i will when i start the job. As a newbie I will have lots of questions and I can already see there are some very helpful people here.

petit_pablo said:

Terminal 2 is only really used with motor on, motor off zones valves. Very uncommon these days.

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thanks for the info. How is the CH switched off if there is no terminal for it?

Terminal 4 is basically a switch that is made live when central heating is required, and then it's turned off when the heating is not required. In the same way that you turn a light 'on' and 'off' with a switch.

stem said:

Terminal 4 is basically a switch that is made live when central heating is required, and then it's turned off when the heating is not required. In the same way that you turn a light 'on' and 'off' with a switch.

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Thanks Stem. So Terminal 3 is the same for hot water? What’s Terminal 1 for?

Terminal 1 is 'Hot Water Off' and it is used when there is a 3-port motorised valve (Y-Plan). As its name suggests, it is made live when the programmer turns the hot water off, and when that happens it powers the motor to move the motorised valve to close off the hot water port.

I anticipate that your next question will be, why then isn't there a wire connected to terminal 2 'Central Heating Off'? The answer is: The motorised valve contains a spring that pulls the valve to the position where the central heating port is closed, as it is not motor driven to this position, but manually pulled by a spring, no electrical supply is required to do this.

Thanks again Stem, lol yes that was my next question.