c/heat blr netaheat mk2 10/16 not heating radiators?

>I presume the CH pump has failed.

no, i would say your system is fully pumped. so if your pump had failed you wouldn't have water either.

> is the pump built into the boiler

no, most times your pump will be next to the copper cylinder in the airing cupboard

>Is this the only possibility


no

check your wall stat is clicking when turned up
if so then go to the airing cupboard and locate the copper cylinder your pump should be located next to that, and next to the will be a valve or maybe two depending if it's a y / s plan system
on the side of the valve is a lever in a slot push the lever across, it will have tension and slot the lever into the end groove. the boiler should fire up.

hi-spec plumbing
July 2007