On Mon, 17 Oct 2005 19:31:49 +0000, Andrew Gabriel wrote:

In article ,
"Peter" writes:
Hi,
I've got a Honeywell programmer controlling my central heating and ho****er.
The power to it comes from a swiched fused spur. This is fitted with a 3A
fuse.
About every two weeks the 3A fuse blows.

I'm assuming the programmer is faulty,

Why?

but before I replace it, could there
be anything else causing the 3A fuse to blow?

Boiler, pump, diverter valve, thermostat, interconnect cabling...

With electric faults on heating systems the pump is centre stage and then
some unless the boiler is leaking water into its controls.

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html