Swapping mid position valve

The Medway Handyman

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Mar 30, 2013, 10:07:33 AM3/30/13

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Swapping a Sunvic SD 2701 mid position valve for a Honeywell V4073A.

Sunvic has 4 wires; blue, grey, orange & white.

Honeywell has 5 wires; blue, grey, orange, white & earth.

Wires from wiring centre, via junction box are brown, blue, black &
earth. I'm guessing it's not the correct cable & the earth is being
used for something else.

Connections are (wiring centre to valve); earth to white, blue to blue,
brown to orange, black to grey.

What do I do with the spare earth wire?

Or do I need to investigate the wiring centre?

--
Dave - The Medway Handyman www.medwayhandyman.co.uk

Owain

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Mar 30, 2013, 11:03:33 AM3/30/13

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On Mar 30, 2:07 pm, The Medway Handyman wrote:
> Swapping a Sunvic SD 2701 mid position valve for a Honeywell V4073A.
>
> Sunvic has 4 wires; blue, grey, orange & white.
>
> Honeywell has 5 wires; blue, grey, orange, white & earth.
>
> Wires from wiring centre, via junction box are brown, blue, black &
> earth. I'm guessing it's not the correct cable & the earth is being
> used for something else.
>
> Connections are (wiring centre to valve); earth to white, blue to blue,
> brown to orange, black to grey.
>
> What do I do with the spare earth wire?

The earth wire is not spare. It MUST be connected to the circuit
protective conductor.

> Or do I need to investigate the wiring centre?

If the cpc in the existing cable is being used for another purpose it
MUST be disconnected from whatever it's being used for, and connected
to earth. An additional/new cable (with cpc) MUST be run in if the
number of cores in existing is inadequate.

The cpc must be tested for continuity back to the main earth terminal
(MET).

Owain

The Medway Handyman

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Mar 30, 2013, 11:27:16 AM3/30/13

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On 30/03/2013 15:03, Owain wrote:
> On Mar 30, 2:07 pm, The Medway Handyman wrote:
>> Swapping a Sunvic SD 2701 mid position valve for a Honeywell V4073A.
>>
>> Sunvic has 4 wires; blue, grey, orange & white.
>>
>> Honeywell has 5 wires; blue, grey, orange, white & earth.
>>
>> Wires from wiring centre, via junction box are brown, blue, black &
>> earth. I'm guessing it's not the correct cable & the earth is being
>> used for something else.
>>
>> Connections are (wiring centre to valve); earth to white, blue to blue,
>> brown to orange, black to grey.
>>
>> What do I do with the spare earth wire?
>
> The earth wire is not spare. It MUST be connected to the circuit
> protective conductor.

When I say spare earth I mean spare green/yellow. The green/yellow is
connected to the white on the actuator. In the wiring centre its
connected to a green/yellow from the RF room stat. Neither are
connected to the earth from the mains input.

I suspect the Sunvice was double insulated & the Honeywell isn't?

And that 'any old' cable has been used in the past.

Point taken re the earth, that can be easily done.

>
>> Or do I need to investigate the wiring centre?
>
> If the cpc in the existing cable is being used for another purpose it
> MUST be disconnected from whatever it's being used for, and connected
> to earth. An additional/new cable (with cpc) MUST be run in if the
> number of cores in existing is inadequate.
>
> The cpc must be tested for continuity back to the main earth terminal
> (MET).
>
> Owain
>

Owain

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Mar 30, 2013, 11:30:52 AM3/30/13

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On Mar 30, 3:27 pm, The Medway Handyman <davidl...@blueyonder.co.uk>
wrote:

> When I say spare earth I mean spare green/yellow. The green/yellow is
> connected to the white on the actuator. In the wiring centre its
> connected to a green/yellow from the RF room stat. Neither are
> connected to the earth from the mains input.

It'll all have to be rewired properly, then.

> I suspect the Sunvice was double insulated & the Honeywell isn't?

Possibly.

> And that 'any old' cable has been used in the past.

Probably done by a lead-basher ...

Owain

The Medway Handyman

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Mar 30, 2013, 1:40:02 PM3/30/13

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On 30/03/2013 15:30, Owain wrote:
> On Mar 30, 3:27 pm, The Medway Handyman <davidl...@blueyonder.co.uk>
> wrote:
>> When I say spare earth I mean spare green/yellow. The green/yellow is
>> connected to the white on the actuator. In the wiring centre its
>> connected to a green/yellow from the RF room stat. Neither are
>> connected to the earth from the mains input.
>
> It'll all have to be rewired properly, then.
>
>> I suspect the Sunvice was double insulated & the Honeywell isn't?
>
> Possibly.

Checked it out & the Sunvic is DI, Honeywell isn't.

>
>> And that 'any old' cable has been used in the past.
>
> Probably done by a lead-basher ...

Indeed, bastard! He had used a junction box & some 3 core & earth, using
the green/yellow as the white.

All re wired & earthed now.

Thanks mate.

ARW

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Mar 30, 2013, 1:18:50 PM3/30/13

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Come on Dave - someone has extented the Sunvic cable with a 4 core flex.
Just buy some 5 core flex and the colours will make sense when your replace
it.

--
Adam

The Medway Handyman

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Apr 1, 2013, 5:19:01 AM4/1/13

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Ferzackerly what I did. Once I twigged the Sunvic was double insulated &
didn't have an earth cable.