The Gledhill BoilerMate....
The Gledhill BoilerMate is similar to a PulsaCoil, but is heated by a gas (or
oil) boiler instead of electricity. It provides hot water (at mains pressure),
and heats the house/flat as well via conventional steel panel radiators.
It is 'open vented', which means there has to be a small header tank fitted
above it which keeps the system topped up with water.
There are three pumps on the unit (which seems like overkill!) but they have
separate functions. One circulates water from the boiler to the thermal store to
heat it, a second circulates thermal store water around the radiator circuits
when the CH is on, and the third pumps water through the domestic water heat
exchanger when a hot tap is turned on.
f you have a BoilerMate that isn't working, before calling an engineer out
you can check yourself that he unit is actually full of water. The top-up tank fitted separately
above sometimes need to be manually filled/topped up. I see many installations
where this tank has no overflow pipe fitted, which means the water supply to the
float valve is best kept turned OFF. This means the system needs to me manually
topped up periodically by turning the isolation valve ON for a minute or so,
then back OFF.
Other things that go wrong (for which you WILL need an engineer) are: the
thermistor flow sensors fail, and earlier models
have a mechanical blender valve that breaks when water scale accumulates inside
it. Less common problems are circuit board failure, scaling of the plate heat
exchanger, or (on early models) scaling of an internal heat exchanger that
needs chemical descaling to cure.
I've written more at www.boilermate-repairs.co.uk