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15.6
DRAINING BOILER SYSTEM
The boiler must be drained if it is to be shut down and exposed to freezing temperatures. Maintenance and service
procedures may also require draining the boiler.
1.
Turn off the boiler electrical disconnect switch.
2.
Connect a hose to the system drain valve.
3.
Locate hose’s discharge in an area where hot water will not cause any damage or injury.
4.
Close the cold-water inlet valve from the header tank or pressurisation unit to boiler system.
5.
Open the drain valve.
6.
Working systematically from the highest point in the heating system, open bleed valves to allow the
system to drain.
7.
Close all bleed valves
8.
If the boiler is being drained for an extended shutdown, it is suggested the drain valve be left open
during this period.
NOTE: The heat exchanger cannot be completely drained of water without purging with compressed air at a
pressure of 1 bar.
15.7
REFILLING THE SYSTEM
1.
Close the drain valve.
2.
Open the cold-water inlet valve from the header tank or pressurisation unit to boiler system.
3.
Working systematically towards the highest point in the system, open all bleed valves and allow any
trapped air to escape.
4.
Follow the lighting instructions as detailed in
Section 13.4.3:
PROCEDURE FOR INITIAL LIGHTING
.
5.
Check for water leakage and airlocks, remedy as necessary.
15.8
OTHER CHECKS
15.8.1
RELIEF VALVE
At least once a year, the pressure relief valve should be checked to ensure correct operation. To check the valve, the
manual override lever should be operated several times. The valve should seat properly and operate freely.
If water does not flow, drain the boiler, remove the inoperative valve and inspect for obstructions or corrosion.
Replace with a new valve of equivalent size as necessary.
15.8.2
FLUE SYSTEM
Examine the exhaust and air intake system at least once a year. Points of inspection are as follows:
1.
Check for obstructions and/or deterioration of flue piping and terminal. Replace immediately where
needed.
2.
Check the terminal for any foreign material and remove as necessary.
3.
Check all flue system connections for leakage and reseal as required.
4.
Check that ventilation grilles comply with current regulations.
15.8.3
CONDENSATE NEUTRALISATION KIT
If fitted the condensate neutralisation kit will require replacing after 12 months of operation. Please refer to the item
specific instructions for further details.
