9. Maintenance
We recommend a planned maintenance contract with
an installation company
In accordance with DIN 1988, part 8, the following measures
must be taken:
9.1. Inspection
9.1.1. Pressure reducing valve
Interval: once a year
1. Close shutoff valve on outlet
2. Check outlet pressure using a pressure meter when there
is zero through-flow
• If the pressure is increasing slowly, the valve may be
dirty or defective. In this instance, carry out servicing
and cleaning
3. Slowly open shutoff valve on outlet
9.2. Maintenance
Frequency: every 1-3 years (depending on local
operating conditions)
To be carried out by an installation company
1. Close shutoff valve on inlet
2. Release pressure on outlet side (e.g. through water tap)
3. Close shutoff valve on outlet
4. Loosen hexagon nut
Caution !
There is a spring in the spring bonnet. It may cause
injuries if the spring is derailing.
• Make sure tension in compression spring is slak-
kened!
5. Slacken tension in compression spring
• Turn control adjustment screw to the left (-) until it does
not move any more
6. Unscrew spring bonnet
7. Check that diaphragm, seals, guide and seating bush are
in good condition, and if necessary replace them
8. Reassemble in reverse order
11. Troubleshooting
Problem
Beating sounds
Water is escaping from the spring
bonnet
Too little or no water pressure
homecomfort.resideo.com/
GB
10. Disposal
• Grey cast iron housing
• Cast iron spring bonnet
• Bronze valve seat
• Bronze piston guide
• Cone up to DN150: brass, DN200: steal
• Spring steel adjustment spring
• EPDM diaphragm
• EPDM seal collar
• EPDM sealing washers
• Stainless steel screws and nuts
Cause
Pressure reducing valve is too
large
Diaphragm is faulty
Shutoff valves up- or downstream of the
pressure reducing valve are not fully open
Pressure reducing valve is not set to the
desired outlet pressure
Pressure reducing valve is not fitted in flow
9
Observe the local requirements regarding correct waste
recycling/disposal!
Remedy
Call our Technical Customer Services
Replace diaphragm
dire
ctio
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MU1H-1007GE23 R1020