INSTRUCTIONS FOR SERVICING
SMALLER TM1520A VALVE
1. Remove screw, snap cap, and pointer.
2. Loosen LTR set screw.
3. Turn off hot and cold supplies at screwdriver checkstops. Remove
M20-2C(CP) cover screws to release cover and thermostatic
control assembly.
4. To remove bridge assembly, M20-1-8B, remove pointer rod nut
(MU-10B) and pull bridge assembly off control rod.
5. To clean, submerge bridge in clean water or non-corrosive
cleaning solution.
DO NOT USE ABRASIVES!
Be certain
thimble moves freely on the port sleeve. Note! Driving stud
(M20-14B) must engage slot in thimble when reassembling.
6. To clean thermostat coil, remove retaining ring and stop, loosen
gland nut. Push rod through cover. Be careful not to pull coil out
of shape.
7. Clean with a non-corrosive cleaning solution.
DO NOT USE
ABRASIVES!
INSTRUCTIONS FOR SERVICING
LARGER TM1520A VALVE
1. Remove screw, snap cap, and pointer.
2. Loosen LTR set screw.
3. Turn off hot and cold supplies at screwdriver checkstops. Remove
cover screws to release cover and thermostat group.
4. To clean, port sleeve assembly (the thimble must slide freely on
the port sleeve): unscrew the check nut as far as it will go, then
screw the port sleeve nut into base. The port sleeve and thimble
may then be lifted out.
5. To clean thermostat coil, remove coil sleeve stud and take off
thermostat group.
6. Clean with a non-corrosive cleaning solution.
DO NOT USE
ABRASIVES!
7. When reassembling, make sure driving ball of thermostat group
engages the ball socket of the port sleeve assembly.
THERMOSTAT
GROUP
POINTER
DRIVING
BALL
PACKING
SOCKET
BALL
FLANGE
M20-2C (CP)
COVER
SCREWS
GASKET
COVER
M20-3C
POINTER
SNAP CAP
CONTROL ASSEMBLY
THERMOSTATIC
TM28-1-12B
POINTER SCREW
W/WASHER
COVER SCREWS
(4 REQ'D)
LTR SCREW
NUT
CHECK
THIMBLE
PORT
SLEEVE
PORT
SLEEVE
NUT
M20-1-8B
BRIDGE ASSY
MU-10B
POINTER ROD NUT
THIMBLE
P.S. HOLDER NUT
M20-5B
PORT SLEEVE
TROUBLESHOOTING INSTRUCTIIONS
Note: Provide valve serial number when ordering parts for each valve!
Small Valve
Repair Kit 1/M20
(Packings & Gaskets)
Repair Kit R/M20 TM-20
(Rebuilding Kit) or M20-
1-8B Bridge Assembly
Repair Kit R/M20
(Rebuilding Kit) or M20-
G2 Thermostat Group
Repair Kit 4/M20
(Checkstop Kit)
Large Valve
Repair Kit 1/125Y
Repair Kit R/125
Repair Kit R/125 or TGM-
125
Repair Kit 2/50Y
1. Leak at stem
2. Leak between valve cover and base.
3. Valve delivers either all hot or all cold
water, or will not mix consistently.
4. After cleaning or replacing port
sleeve/bridge assembly, valve performance
is not consistent.
5. Hot water by-pass into cold line (or cold into
hot).
6. Supplies cannot be shut off completely.
Supplies leak at checkstop bonnets.
PACKING & GASKETS
PORT SLEEVE/BRIDGE
ASSEMBLY
THERMOSTAT GROUP
CHECKSTOPS
See pages 10 & 11 for parts Breakdowns
9
