Replacing heating programmable timeswitch

Joined
27 Jan 2005
Messages
12
Reaction score
0
Country
United Kingdom
Hello, i'm replacing my broken Thorn EMI programmer (believe based on a Honeywell 42003744) with a Sunvic i picked up at B&Q.

It is for a boiler feeding heat and h/w.

Looking for advice on the wiring terminals.

Basically, the Thorn had 8 terminals and the Sun only has 6

The wiring diagram on the Thorn is as follows:

H/W - terminals 8, 7, 6 are for COM, NC & NO respectively
Heat - terminals 5, 4, 3 are for COM, NC & NO
N and L obviously

The Sun is:

Terminals 1 (H/w off); 2 (heat off); 3 (H/w on); 4 (heat on) + N & L

The Sunvic is a dual channel so i bought the right one.

Just wondering which i can double up on and which must remain separate!

Thanks in advance,

Liam

Liam
 
Sponsored Links
The wiring diagram on the Thorn is as follows:

H/W - terminals 8, 7, 6 are for COM, NC & NO respectively
Heat - terminals 5, 4, 3 are for COM, NC & NO
N and L obviously

The Sun is:

Terminals 1 (H/w off); 2 (heat off); 3 (H/w on); 4 (heat on) + N & L

On your old programmer, NO is the equivalent of call for heat, whereas NC is heat off. Both com terminals had probably been linked to L on the old programmer, but it would appear this is done internally on the replacement you have purchased.

So:

Sun terminal 1 = Thorn terminal 7
Sun terminal 2 = Thorn terminal 4
Sun terminal 3 = Thorn terminal 6
Sun terminal 4 = Thorn terminal 3
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Back
Top