Replacement CH and Hot Water programmer.

[bananas and custard]

Hi,

I want to replace an aging Randall 4033 Heating and Hot water prgrammer, see wiring diagram below, with a new electronic unit.

As I don't want to chase any more wires into the tiled wall can anyone recommend an appropriate compatible replacement please?

As there is a common present does this have to be used or can a new electronic prgrammer without common terminals be used, such as Dandoss Mk18? Equally can the common be shared for a programmer requiring common on heating and water, Danfoss SET3E.

Mk18 FP715

SET3E

I would state that I'm after advice before calling a pro, I just want to understand what I'm talking about a bit more first.

Many thanks.

 

[Taylortwocities]

I've used these quite a lot: http://www.screwfix.com/app/sfd/cat/pro.jsp?id=27967&ts=47358#

It comes with a big list of old programmers each with detail telling you where to put your wire from the old programmer onto the new one.

TTC

 

[RF Lighting]

I would go with the two channel horstmann programmer like the one that TTC reccomended.

I have one in my kitchen. They are easy to use, and not too ugly, and will be fine as a direct replacement for your existing randall programmer.

You currently have a two channel programmer, so will need This one

The one in TTCs link is only single channel.

 

[Taylortwocities]

Glad that your on the ball RF!

TTC

 

[bananas and custard]

That'll do me, thanks.

There's a Screwfic trade counter 5 miles away so I'll call in tomorrow.

Thanks again.