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6.4 OPERATION OF HOT WATER SAFETY VALVES
Slowly open the temperature and pressure relief valve by twisting its cap for a few seconds.
1.
Check water is discharged and that it flows freely through the tundish and discharge pipework.
Release the valve cap and check water flow stops and valve re-seats correctly.
Repeat step 2 for the expansion relief valve located on the cold water combination
2.
valve.
6.5 OPERATION OF PRIMARY SYSTEM SAFETY VALVE
Close the central heating flow and return isolating valves.
1.
Slowly open the central heating system pressure relief valve by twisting its cap for a few
2.
seconds.
Check water is discharged and that it flows freely through the tundish and discharge
3.
pipework.
Release the valve cap and check water flow stops and valve re-seats correctly.
4.
6.6 PRIMARY SYSTEM EXPANSION VESSEL CHARGE PRESSURE
Drain the central heating primary circuit (see section 8.2 page 57) until the central heating
1.
pressure gauge reads 0 MPa (0bar).
Remove the dust cap from the central heating expansion vessel.
2.
Check the charge pressure of the expansion vessel using a tyre pressure gauge. The
3.
pressure (with system de-pressurised) should be 0.1 MPa (1.0bar). If lower than the required
setting it should be re-charged using a tyre pump (Schraeder valve type). DO NOT over
charge. Re-check the charge pressure and when correct replace the dust cap.
Connect the filling loop. Open the filling loop isolating valves and allow system to repressurise
4.
to approximately 0.15 MPa (1.5 bar).
Close the filling loop isolating valves and remove the flexible hose.
5.
6.7 ELECTRICAL CHECKS
Inspect all electrical terminations for signs of over-heating.
1.
Check all terminations are tight.
2.
Check cable glands are tightened and grip cables secure.
3.
6.8 SOLAR HEAT TRANSFER FLUID
Using an antifreeze tester check that the value is approximately -21ºC (40% concentration)
6.9 SOLAR COLLECTOR
Check the collector for signs of leaks, damage and contamination.
