Morco FEB-24E - Central Heating Operation and Potential Issues; Time Clock Functionality; Slow Heating to Reach Temperature

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Important - Leaks on the heating circuit can occur anywhere on the system. It is important
to locate and rectify any leak however small it may be. One way of detecting minute leaks
is to pressurise the boiler to 2.0bar. Using toilet or tissue paper, wipe around any joints on
the system. If any moisture is present then the tissue will change colour becoming darker.
Check the following if low pressure is shown:
 Radiator air vent screws and blanking plugs
 Radiator valves all joints and unions
 Filling loop double check valve
(This may not be visible without removing inspection panels)
 Boiler connections including safety valve (check discharge pipe)
 Automatic air vent bleed screw (located on top of pump)
 Drain plugs and connections under the van. Any leaks are usually indicated by
dark patches on the concrete or gravel, or look for patches of dead grass.
 Loss of pressure from expansion vessel (see section under expansion vessel)
If the leak is impossible to detect then the last resort is to introduce a proprietary leak
sealing chemical into the system such as Fernox LS 3.
TIME CLOCK
Check that the time clock is calling for heat, the white tappets should be in the outer
position at the arrow head.
IMPORTANT. The specification of time clocks on boilers after serial number 050512656
incorporates a three position selector switch located at the base of the clock. There are
three positions as follows:
1. Switch to the left overrides timed positions and heating is on constant.
2. Switch in the centre position heating is on or off according to tappet timed
positions on the clock
3. Switch to the right heating is off.
HEATING SLOW TO REACH TEMPERATURE
The main burner may ignite for short periods only and the radiators may be slow to heat.
This can be caused by a blocked filter on the central heating return pipe. (Right hand
pipe). Access to the filter requires draining down the boiler, and removing the pipe fitting
from the boiler. The filter can then be removed for cleaning and MUST be replaced to the
boiler.