How do you know if your Gledhill PulsaCoil BP is scaled up?
The hot water at your tap will be cooler than it was. Indeed, it can be almost cold.
If the build-up of limescale is severe then you may find your water flow reduced
too. However, you can’t be sure what the problem is because the store might not be
heating up properly. So check the obvious first - that the store of water is actually
How can you do this?
Remove the front cover of your PulsaCoil BP and look at the picture.
Feel the pipes, are any of them hot?
If yes then at least the store is heating up. If you have turned the boost immersion
heater on then this check isn’t valid. Turn the boost off and wait 24 hours - then
see if this pipe is hot.
So you’ve done that and the pipe isn’t hot.
Then the most likely problem is the lower immersion heater. Call us and we’ll replace
Or...the pipe IS hot (and you haven’t activated the boost) but you still haven’t
got hot water.
Then it’s either going to be the thermostatic mixer valve (in which case call us
and we’ll replace it) or the internal heat exchanger has scaled-up. Call us and we’ll
descale it for you.
PulsaCoil A-Class not giving hot water?
The A-Class has electronics which control its function. Unlike an ordinary immersion-heater
based water heater, the A-Class controls its heat by use of sensors rather than thermostats.
These sensors tell the printed circuit board (PCB) that they are happy, or not. But
it gets far more complicated than that. There are also relays controlling the switching
of the off peak and the boost. There’s also a pump that has its speed control governed
by the PCB, and electrical relays too! There’s also a plate heat exchanger which
suffers from limescale. Call us if you think yours has scaled up, and we’ll replace
it for you. A-Class acting odd? Hot water sometimes but not others? Highly likely
to be one of the two sensors (GT198) - and best to replace both the cold and hot
ones. A word of caution if you have decided to do this yourself! We know that there
are companies selling this part that will supply the part only - without the nuts
& olives. This is because GT198 is used as a sensor elsewhere as a dry sensor. Make
sure you order the nuts & olives as well as GT198. Fitting the new ones (which you
would think would be easy) can cause water leaks. The new sensors can be a tight
fit, and it’s very important that you have crushed the olives onto the sensor body.
To do so requires tightening the nut considerably (more than you usually would with
such a small nut) and a sealant. Hold the octagonal brazed nut as you tighten with
another spanner. Some of them have to be ridiculously tight to ensure they don’t
leak, and you sometimes feel they are going to break apart! More often than not,
A-Classes are fitted in upstairs flats, so if these leak then you won’t know about
it until the flat below you complains about their ceiling! Engineers like me already
have the sensor housing kicking about in our toolboxes, so we crush the olives on
before we fit them, but that won’t be obvious to a diyer. Maybe best to call us or
someone else who is used to working on A-Classes.
PulsaCoil III or 2000
This appliance is relatively simple, but it still has relays, a PCB, control sensors
and that plated heat exchanger. So some of the faults that apply to the A-Class also
apply here. There’s also a little red LED on the PCB. This can indicate the nature
of a fault...but not always! If your PulsaCoil has a fault then tell us (by email
please) how that red light is flashing and we MAY be able to tell you the problem.
The Plated Heat Exchanger
Many Gledhill appliances use this heat exchanger, the GT107 - and it really gets
scaled up! We don’t usually recommend descaling it as it is usually quicker to simply
replace it with a brand new one. The cost is £168.00 including vat, but plus delivery/fitting.
However, we have reconditioned GT107 HEs for £84.00 plus delivery/fitting.
BoilerMate (like a PulsaCoil, but not)
See the brass valve with the white cap on top at the top left of the picture? That’s
the thermostatic mixer valve (or blending valve). It is connected to the internal
coil heat exchanger. The coil inside BoilerMates and similar appliances gets completely
blocked with limescale. This can mean cooler water and/or reduced flow. We can easily
descale it for you - just call us.
The Gledhill PulsaCoil is perhaps one of the ‘better’ thermal store hot water heaters.
‘Better’ because it works ‘vented’ rather than ‘unvented’. It provides enough hot
water on overnight tariff for the needs of two people - if showers rather than baths
are taken. However, it does have electronics, especially the A-Class, which can be
troublesome. In hard water areas the heat exchanger is particularly prone to limescale
too. By far the best is the PulsaCoil BP. But before you email or call us just check
one thing (which can cause a ‘fault’ that isn’t really there)...check that there
is sufficient water in the ‘feed and expansion’ tank!
We are used by many housing associations and national property development companies
to attend to faults with Gledhill Torrents, PulsaCoils and BoilerMates. PLEASE NOTE
we do NOT attend to other Gledhill appliances - other than replace them with an equivalent
heater - see here.