What Cable?

[PlumbersMate]

Hello one and all. Have a customer with a Potterton Performa Combi.

It has an integral Time Clock but he wants to convert this to an External 24 hour/7 day timer. Question is which cable will I need for this? Cheers

 

[Barry98]

2.5 flex is what we use I think , would have to go van to confirm lol

 

[PlumbersMate]

2.5 flex is what we use I think , would have to go van to confirm lol

Thanks Bod. I thought that myself but someone I know mentioned 5 core? So 2.5 flex would be sufficient to remove internal timer and wire a new external one?

 

[Barry98]

Maybe 5 when you have a separate stat and timer ?

 

[Barry98]

2.5 is the diameter of the cable

 

[gassafe]

Can you just fit a external programmable room thermostat like the Honeywell 927, that just requires 2 wires

 

[dancinplumba]

i use 1.5mm2,
cos its a combi you can use three core
imho

 

[Barry98]

I think you can just 1mill tbh but I'd be more tempted to check with a spark , there I a reason we carry 2.5 which I know is too big but there is a reason just can't think of it

 

[dancinplumba]

I think you can just 1mill tbh but I'd be more tempted to check with a spark , there I a reason we carry 2.5 which I know is too big but there is a reason just can't think of it

will it be for immersion heater ?

 

[Barry98]

Can you just fit a external programmable room thermostat like the Honeywell 927, that just requires 2 wires

Don't know that timer but it would normally need a power supply then a switch for the timer

 

[dancinplumba]

wired 927 is battery powered and can use 2 core for switching

 

[gassafe]

Don't know that timer but it would normally need a power supply then a switch for the timer

The Honeywell is powered by 2 AA batterys, it only requires switch wires then minimum 0.75mm i believe

 

[PlumbersMate]

he has already bought a Horstmann C17. Basically the boiler is in a students bedroom so when he wants to alter the heating etc he has to disturb said student. What he has asked me to do is remove the internal clock, and wire the external Horstmann clock from boiler to cupboard downstairs.

 

[DIY Bob]

1.0mm should be good enough, or even 0.75mm if fused down - there's no real load to speak of. 2.5mm for water heaters / immersion heaters.

 

[PlumbersMate]

1.0mm should be good enough, or even 0.75mm if fused down - there's no real load to speak of. 2.5mm for water heaters / immersion heaters.

so 1.0mm 3 core? white flex?

 

[AWheating]

have you checked the boiler and timers instructions?

if your unsure then run 5core flex, 1.0mm or even .75 as mentioned should be fine.

 

[PlumbersMate]

ive googled instructions for both but seems alot of electrical jargon which i dont quite understand. Am hoping that when i get timer out of box at customers all will become clear in instructions. Just wanted to take right cable with me, and get a rough idea of what i needed to do as have found alot of different answers from my research on the web