I have just received a replacement 2 port actuator for the above and note that the cable is not the same as the original. This had a live, neutral and earth whereas the new one has live, neutral, no earth and 2 additional wires (grey and orange)
I assume that the earth is now not reqd but do not know what the grey/orange are for Can i just cut them back?
Many thanks
Mike
The extra wires are connected to a microswitch which closes as the valve opens. If you have several zones, these are normally parallel up and used to switch a live to the boiler to fire it up. The idea is that if any zone opens, the boiler runs. This is the classic S-plan arrangement.
Could it be that you had a kind of sub-zone before? In other words one run from a point downstream of the main CH zone or diverter valve? This could be a reason that the switch isn't used, but it's not a good design because the downstream valve could be open and heat required, but the main one closed.
The correct way to configure this is the S-plan plus arrangement where multiple valves connect to the same place on the plumbing and the microswitch wiring is paralleled.
Possibly you don't have any of this, but I thought it worth mentioning, because it is odd that the switch is not used.
I'm surprised there isn't an earth. Maybe the electrics are double insulated? Is there a symbol on the casing with one square inside another?
Have a look at S-Plan in
What sort of heating configuration have you got, and what is this valve used for in your setup?
There are some plastic motorised valves with no earth, but they still have the aux contacts.
Sorry guys! After checking again I realise I was looking at the wrong cable connections in the junction box. All appears to be in order but I can definitely say that there is no earth for this make of actuator (HPA2) Good link though for future ref
Mike
Have something to add? Share your thoughts — no account required.
Ask the community — no account required