INSTALLATION, OPERATION AND MAINTENANCE MANUAL – ORIGINAL VERSION
AVK GATE VALVES FOR WATER AND FIRE PROTECTION
SERIES 145
Page 12/12
MI GateValve 145 rev. AC 2020 GB
7.2.3 SUPERVISORY SWITCH INSTALLATION (Fig. 7A)
1. AVK series 145 OS&Y valves have a pre-tapped 1/2”
NPT threaded hole in the yoke/bonnet (F263) for
mounting a supervisory switch (Fig. 7A).
2. With the valve in fully open position, there is a stem
groove that allows the switch to indicate the open
position.
3. Refer to the switch manufacturer’s instructions for
correct switch installation.
8. TROUBLESHOOTING GUIDE
WARNING
The valve must be isolated before performing any
maintenance. Failure to do so may cause pressure to be
released resulting in severe injury or death.
Several problems and solutions are presented below to
assist you in troubleshooting the valve.
PROBLEM: Valve leaking around stem/gland flange
Probable cause:
Damaged or worn O-rings.
Corrective action:
Refer to the upper and lower stem
seal component repair sections of
this manual and replace the O-rings.
PROBLEM: Valve leaking around bonnet and body
Probable cause:
Bonnet bolts loose.
Corrective action:
Tighten bonnet bolts.
Probable cause:
Damaged bonnet gasket.
Corrective action:
Replace bonnet gasket
PROBLEM: Valve leaking around pipe connections
Corrective action:
Tighten flange hardware.
Corrective action:
Verify gasket is not damaged.
Replace if necessary.
PROBLEM: Valve hard to operate
Probable cause:
Gland bolts too tight or unevenly tightened.
Corrective action:
Loosen and then re-tighten gland bolts evenly.
Probable cause:
If the valve has not been operated over a prolonged period of time, build-up may occur on the internal
parts.
Corrective action:
Open or close the valve one turn at a time until fully opened or closed. Repeat the process a few times
and then flush the system to remove any debris.
Probable cause:
Pressure build-up in system.
Corrective action:
Relieve pressure and bleed off any air build-up.
9. PARTS AND SERVICE
For information on parts and service for your area, please contact AVK International A/S. Make a note of the valve model
number and size which is to be found on the valve and contact:
AVK International A/S
Bizonvej 1
DK 8464 Galten
T: +45 8754 2100
www.avkvalves.eu
page 12
OS&Y (Outside Stem & Yoke) VALVE REPAIRS:
SUPERVISORY SWITCH INSTALLATION
(Fig.8A)
1. AVK Series 145 OS&Y valves have a pre-tapped, 1/2" NPT
threaded hole in the Yoke/Bonnet (F263), for mounting a
Supervisory Switch. (See Fig. 8A)
2. With the valve in the fully open position, there is a stem groove
that allows the switch to indicate the open position.
3. Refer to the switch manufacturer's instructions for correct
switch installation.
Fig. 8A
1/2" NPT
tapped hole
F263
Supervisory
Switch
Stem
groove
Fig. 7A