On Sunday, November 4, 2012 2:52:44 PM UTC, fred wrote:
In article , Harry Davis
writes

Are all the electrics for an oil central heating and hot water system
(pump, timer, stats, etc.) usually all off a dedicated mains fuse? Or all
on the same fused spur from one of the rings?

Or is it common for one of the appliances to be on one ring, another on
another, etc.?

It should all be fed from the same point, it is a safety requirement so
that anyone working on the installation can go to a single location and
isolate the system without the risk of electrocution from some other
source of power back feeding into the control wiring.

Better to find out how yours is fed. And quicker. It should all be of one point, but of course shoulds aren't always followed.


The reason I ask is that we suffer from constant power cuts, and I'm
considering giving myself the option of another supply, either from a
standalone diesel generator or from batteries, thereby enabling us to keep
the heating going. I'd like to have the electrics for the heating system on
their own plug, which could be plugged either into a mains socket or a
socket powered by another supply.

Which ever way you go, make sure you have enough headroom in your genny
or inverter to feed the motor and magnetic loads that make up most of
the c/h system. Others may be able to offer hands on advice but my guess
would be that 100% headroom would be required at least.

Motors draw many times run current during startup, and are the main load on a modern CH system.


NT