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Installation and Servicing
SECTION 3 - SERVICING
3.19 CH PRESSURE RELIEF VALVE
1.
Isolate and drain down the HIU's CH circuit
Refer to Section 3.5.
2.
Pull out and remove the clip (positioned
at the rear of the water set) retaining the
Pressure Relief Valve (PRV).
3.
Undo the PRV outlet pipe connection and
disconnect from the PRV.
4.
Twist and pull the PRV upward to remove it
from the manifold.
5.
Reassemble in reverse order ensuring the
retaining clip is correctly fitted, the pipe
compression fitting re-tightened and return
thermistor is re-clipped.
Note: Ensure the
pipe is fitted in the chassis channel.
6.
Check the 'O' ring seal is clean and
correctly fitted. Refill the HIU. Refer to
Section 2.5.
7.
Check that the HIU operates in both DHW
& CH modes.
8.
Check the operation of the PRV by rotating
the top of the PRV briefly to ensure it
discharges water and reseals.
SER
VICING
