These categories apply to mains gas (or network connected) as well as LPG tank,
cylinder stored gas or oil that are used in more rural or remote areas.
IS IT A CONDENSING BOILER?
Since 2005, all gas boilers (Combi & System) have to incorporate Condensing
technology and is a requirement to achieve the ‘A’ rating.
A condensing boiler captures the heat from the exhaust gases and recycles it to
preheat the incoming water, thus reducing the overall energy consumed.
In the process, water vapour in the exhaust gases is condensed creating a small
amount of water that needs to be drained to waste usually through an outside
wall. To identify this, look for a white pipe at the bottom of the boiler, typically
22mm in diameter.
TOP TIP: In a very cold weather snap the greatest cause of boiler call-outs
is a frozen condensate waste pipe so check that first if your boiler
indicates a fault condition
TURN IT DOWN!!!
If you turn you boiler down to, say, 65°C rather than the more usual 75°C then
your boiler will run more efficiently, typically 3% better. This is because
condensing boilers (see above) only condense when the water returning from
your heating is 58°C or less (to create the cooling effect that causes
condensing). If your return temperature is 60°C or more, your boiler won’t be
condensing, it won’t be achieving the A efficiency rating and you won’t be
maximising your energy savings. By having a lower flow temperature to start
with you can practically guarantee that your return temperature will be below
58°C and so will be operating at maximum efficiency all the time.
When your boiler is serviced, your engineer will do a series of
tests including of the flue gases, which indicate if the boiler is
burning cleanly and thus efficiently. However, you may find that
your radiators or skirting heating are not getting hot, and you
may think this is because your boiler is faulty or needs replacing.
HANG ON! YOUR BOILER MIGHT BE JUST FINE...
MY RADIATORS AREN'T ALL GETTING HOT
If some radiators are getting warm and others
not, chances are it’s trapped air and the
problematic radiators need to be bled. More
seriously it could be sludge in the pipework
caused by the steel radiators rusting from the
inside (skirting heating is usually made from
aluminium so it won’t be rusting). This will
require a flush to clean out the waste, and the
system refilling with clean water and suitable
rust inhibitor.
Skirting Heating is made from aluminium, so will not rust and sludge up your system
IS MY PIPE WORK PAST IT?
In really serious instances, the pipework itself may be
past its sell by date (typically 40~50 years), and so
replacing your boiler because your house is not heating
up is not going to solve the problem.
Your heating engineer should be able to measure the
pressure from and then the return to the boiler with all
the radiators open and see if there is a significant
pressure drop requiring remedial action.
It is common in areas with high levels of calcium carbonate dissolved into
the water, to use a water filter or softener to reduce limescale and improve
the taste. Under no circumstances should chemically softened water be
plumbed into the central heating system. Whilst limescale can build up in
appliances that are constantly being refilled (such as kettles, baths etc) the
water in the central heating is a ‘closed’ system and apart from the
occasional top up (see above) the calcium carbonate levels are static. As
such limescale build up is minimal in closed loop systems especially if plastic
pipe has been used. Introducing chemically softened water can damage
boilers, heat exchangers, aluminium radiators etc. and should be avoided at
all costs. Mechanical or centrifugal filters do not present such a hazard, but
double check the suitability of your heating system to accept softened water.
If in doubt, treat only the domestic potable water.