THERMAFLOW LTD | THERMAFLOW® ELECTRIC COMBINATION BOILER |
Tel: 0870 850 5207
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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 doesn’t resolve the problem, it will be
necessary to change the blender
Strip off the blender and check hot and cold mesh filters for blockage. (Clean if necessary).
3.2.5 Checking the concentration of corrosion inhibitor
We would recommend Sentinel X100, or equivalent. Dose appropriately according to the size of the
Thermaflow and central heating system volume combined and in accordance with the inhibitor
manufacturer’s guidelines.
3.2.6 Preventing pump seizure in summer
To prevent seizure of the central heating pump we recommend you turn the central heating on for 30
seconds or so every few weeks throughout the summer.
Seized pumps can usually be freed. The air release on the pump can be completely removed. A small flat
blade screwdriver can be inserted into the slot in the centre and rotated to free the pump.
3.2.7Checking correct operation of electrical components
WARNING:
BEFORE OBTAINING ACCESS TO TERMINALS, ALL SUPPLY CIRCUITS MUST
BE DISCONNECTED.
3.2.8 Low pressure switch
To check correct operation of the low pressure switch, drain some water from the central heating system
until the pressure falls below 0.5 bar, then check continuity between terminals 1 and 2 there should be no
continuity between these terminals.
Re pressurise the boiler and re check there is continuity between the same terminals.
3.2.9 Control and high limit manual re-set thermostats
Check operation of the control and over temperature thermostats by checking for continuity between both
terminals.
(YOU MAY HAVE TO REMOVE THESE THERMOSTATS IF THE BOILER IS STILL HOLDING HOT
WATER. YOU CAN PLACE THE THERMOSTATS IN A BEAKER OF COLD WATER AND THEN
CHECK FOR CONTINUITY ACROSS THE THERMOSTAT).
3.2.10 CONTROL THERMOSTATS;
There are three or four of these thermostats in total. One is fitted in each heating element. The control
thermostats are individually preset.
They should not be tampered with. If a failure on one of the thermostats has occurred, take note of which
element it was removed from and contact Thermaflow Ltd for spares and advice.
