Telephone Cable used as link from Programmer to pump etc

Pip · Oct 22, 2012

Hi People,

So have been called out to change a Potterton EP2000 programmer for a Horstmann C27, nothing strange in that you think.

When I removed the EP2000 there are telephone cables from certain points, Neutrals, Earths and possibly switched lives, which appear at the other end in the airing cupboard connect to the water tank stat, pump, etc..

Am I missing something here? are these being used to switch on the hot water etc?

They can't be carrying 240 volts surely?

Any help would be appreciated

Pip

Megavolt · Oct 22, 2012

Pip said:
Hi People,

So have been called out to change a Potterton EP2000 programmer for a Horstmann C27, nothing strange in that you think.

When I removed the EP2000 there are telephone cables from certain points, Neutrals, Earths and possibly switched lives, which appear at the other end in the airing cupboard connect to the water tank stat, pump, etc..

Am I missing something here? are these being used to switch on the hot water etc?

They can't be carrying 240 volts surely?

Any help would be appreciated

Pip

Did you not test to see what voltage was present. Are they being used for volt free switching

Pip · Oct 22, 2012

I will admit I put the EP2000 back on and walked away until I could find more info.
So Volt Free Switching could well be there use, just didn't like the fact they ran in the same trunking.channeling as the 240 volt cable etc.

So there being these cable in the system is common then is it?

Megavolt · Oct 22, 2012

Pip said:
I will admit I put the EP2000 back on and walked away until I could find more info.
So Volt Free Switching could well be there use, just didn't like the fact they ran in the same trunking.channeling as the 240 volt cable etc.

So there being these cable in the system is common then is it?

Wouldnt say common but as long as volt free don't see a problem

Pip · Oct 22, 2012

Will admit I'm never happy with central heating wiring, not my strongest field.

So just out of interest, what readings can I expect on these terminals?
Just continuity when closed / Call for heating or water (depending on which terminal of course)

Voltage free suggest they are just that no voltage on these cables, correct?

Pip · Oct 23, 2012

Just an update, 240 volts over all the place!

The 12 core telecomunications cable is split into pairs and runs from the EP2000 programmer on the ground floor to the airing cupboard where it is used to link to the pump, valve and hot water tank stat.

No other live feed in the airing cupboard other than the emersion element, which is off at this time as the boiler is doing the work.

So looks like a fitter who did not have any multi core 1.5mm cable and only had comms wire.

Anyone know the current carrying capacity of telephone wire?

Thanks for your input