resideo NK300S Instrucciones De Instalación página 3

MAINTENANCE
Maintenance of backflow preventer must be carried out
by authorized personnel!
Inspection
NOTES:
— Frequency: Every 6 month (depending on
local operating conditions).
— To be carried out by an installation company.
Inspection with a test control unit and main-
tenance-set (see accessories).
Testing pressure reducing valve
1. Close shutoff valve on outlet.
2. Check outlet pressure on pressure gauge when no
flow is occurring.
• 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.
Testing discharge valve
NOTE: Quick test for the discharge valve:
Lower the inlet pressure: if the discharge valve
opens (drops) and water drains from the valve,
the valve is functioning.
Testing outlet check valve
1. Close the upstream shut off valve (1).
2. While monitoring the discharge valve outlet (2)
loosen the plug (3) carefully and partly only! This
will empty the water between shut off valve and
backflow preventer.
3. When the outlet check valve works properly only a
small amount of water is drained through the dis-
charge valve outlet (2).
4. In case water continuously drops/ flow out of the
discharge valve outlet (2) the outlet check valve
may be cleaned or replaced (see instructions how
to replace).
Maintenance
NOTE: We recommend a planned maintenance con-
tract with an installation company.
In accordance with local codes & standards a regular
maintenance must be taken.
Frequency: To be carried out by an installation company,
depending on local operating conditions.
BRAUKMANN NK300S BOILER FEED COMBINATION
Pressure Reducing Valve insert
1
1. Close shut off valve on inlet and outlet.
2. Release pressure on outlet side.
• E.g. loosen the closing plug 1.
• Afterwards screw in closing plug again.
3. Slacken tension in compression spring.
• Turn adjustment handle counter clockwise (-)
until it does not move any more.
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
slackened!
4. Unscrew spring bonnet.
• Use spanner.
5. Remove slip ring.
6. Remove valve insert with a pair of pliers.
7. Check that sealing ring, edge of nozzle and slotted
ring are in good condition, and if necessary replace
the entire valve insert.
8. Reassemble in reverse order.
9. Set outlet pressure.
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2
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M36865
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M36866
33-00339EFS—05