9.3.4
Safety overheat thermostat
1. Pull the two spade connections off the safety overheat thermostat.
2. Remove the screws securing the thermostat to the mounting plate on
the flow pipe and remove it.
3. Fit the new safety overheat thermostat to the mounting plate with the
two screw previously removed.
4. Connect the two spade connections to the safety overheat thermostat
ensuring that they are pushed fully on.
9.3.5
Pressure Gauge
1. Drain the primary circuit and undo the nut on the pressure gauge
capillary.
2. Ease the two retaining tabs holding the pressure gauge bracket away
and remove the bracket.
3. Remove the gauge assembly.
4. Examine the sealing washer on the pressure gauge capillary, replace
if necessary.
5. Reassemble in reverse order with the new pressure gauge.
9.3.6
Safety pressure relief valve
1
Safety pressure relief valve
2
"O" ring seal
3
Sealing grommet
4
Discharge pipe
5
Grub screw
1. Drain the primary circuit.
2. Disconnect the discharge pipe from the valve and remove the sealing
grommet.
3. Using a suitable hexagon key undo the grub screw sufficiently to
release the valve.
4. Note the orientation of the valve, rotate it and withdraw it from the
manifold.
5. Fit the new valve and ‘O’ ring seal and set to the previously noted
orientation. Tighten the grub screw.
6. Reconnect the discharge pipe ensuring the sealing grommet is in
place to maintain the integrity of the case seal.
Fig.50
Removing safety overheat
thermostat
PN-0000383
Fig.51
Remove safety pressure relief valve
PN-0000622
5
1
3
2
4
9 Maintenance
52
