Central Heating Programmer

[trigg3r]

Hi Guys,

I need to change over my Central Heating Programmer, as my Sangamo M5 is knackered. I've purchased a Horstmann 425, which is a replacement, but could use some advice on the wiring, if anyone can help please.

I think I have it almost figured out, but I just want to be sure.

Here is the wiring for my Sangamo M5 at the moment:

Untitled

• trigg3r
• 31 Jan 2011
• 1

Now, the Horstmann has a comparison wiring diagram which is located here:
http://www.horstmann.co.uk/downloads/ElectronicDocuments/Central-Heating/WiringGuide.pdf

So, as I understand it, I should do the following:

Sangamo M5 ---------------------------------- Horstmann 425
Earth--------------------------------------------Earth
Terminal 4 and 5-------------------------------Neutral
Terminal 3--------------------------------------Live
Terminal 1--------------------------------------Terminal 1 (HW On)
None--------------------------------------------Terminal 2
None--------------------------------------------Terminal 3 (HW Off)
Terminal 8--------------------------------------Terminal 4 (CH On)
None--------------------------------------------Terminal 5
None--------------------------------------------Terminal 6 (CH Off)

As you'll notice in the picture attached, there's a link to Terminal 6, which goes to Terminal 1, can this just be removed now?

Any help appreciated.

Many thanks,
Callum

 

[trigg3r]

Can anyone give me advise on this please?

Many thanks,
Trigg3r

 

[holmslaw]

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[trigg3r]

Yep! I've been given a medal! I've used the same broom for years! Only needed to change the head and handle a few times!

I'm not sure what you mean by:

'But you do need to link terminals L - 2 - 5.'

Live is already connect to the live terminal on the 425, and 2 isn't needed and 5 is neautral on the Sangamo and will be rewired to the neutral terminal on the 425?

Cheers,
Trig

 

[holmslaw]

..

 

[trigg3r]

Ahh I see that now, thanks!

I wonder why it needs that linked like that?

Thanks for the help Dave.

Cheers,
Trigg3r

 

[holmslaw]

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