THERMAflow Ltd | THERMAFLOW® ELECTRIC COMBINATION BOILER |
Tel: 0870 850 5207
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WARNING: FOR YOUR OWN SAFETY
SERVICING AND MAINTENANCE SHOULD BE CARRIED OUT BY A PERSON WHO IS
COMPETENT TO DO SO.
3.2 MAINTENANCE
•
Before commencing, refer to section 1. Installation
Checking the primary expansion
3.2.1 The primary expansion - internal
(volume 15 or 17 litres) is internal of heating boiler. Its purpose
is to take up expansion in the boiler and central heating system.
The expansion bubble automatically forms when the system is filled to the correct pressure
3.3.2 The secondary expansion vessel
(volume 0.5 litres) is the white or silver vessel connected to the
cold inlet of the boiler.
Its function is to take up expansion in the hot water pipe work and so protect the blender from damage.
The pressure can be accurately checked with the pressure relieved on the other side of the diaphragm.
To do this, isolate the water supply to the Thermaflow boiler and open a hot tap. Water will run for a few
seconds then stop.
Connect a pressure gauge to the car tyre type valve on the vessel. The pressure should register 200-350
KPA (2.0-3.5 Bar). Close the hot taps and turn the water supply back on.
3.2.3 Checking the inline strainer
Whilst the water is off, remove and clean the gauze in the brass strainer assembly. To remove the gauze
for cleaning un-screw the brass plug.
3.2.4 Checking the hot water blending valve
With the store temperature fully recovered, run a hot tap and check the flow rate and temperature.
If the hot water has deteriorated suddenly (over less than a month) then this points to a problem with the
blender.
A broken blender is usually linked to a loss of pressure in the secondary expansion vessel.
The expansion vessel protects the blender from damage when the water in the secondary system
expands as the water re-heats after water is drawn off.
Check the pressure in the secondary expansion vessel as detailed previously in section 2.
If it does not hold pressure it will need to be changed. If this do
esn’t resolve the problem, it will be
necessary to change the blender
