Honeywell Thermostatic Mixing Valve Installation Guide

Page of 12
AM-1 SERIES™
3
62-3075EFS—05
supply to provide mixed tempered water to connected 
fixtures. This provides constant water temperature under 
different working conditions.
MAINTENANCE PROCEDURES
Hard water conditions may result in scale deposits, 
causing binding of internal parts in extreme cases. 
Cleaning the internal parts will usually restore the valve to 
proper operating conditions. In some cases, it may be 
necessary to replace the lower assembly.
To clean and/or replace the lower assembly, shut off water 
and:
1.
With a screwdriver, remove screw and handwheel.
2.
Loosen upper nut (do not remove) to allow engaging 
an adjustable wrench on lower nut. Unscrew lower 
nut (counterclockwise). This removes top assembly.
3.
Brass top assembly will pop up. Remove lower 
assembly, diffuser and spring.
4.
Carefully remove any scaling (calcium deposit) or 
foreign particles from valve seat and other internal 
parts. Use vinegar to remove calcium. Soak parts 
until calcium becomes soft and can be scrubbed and 
washed off. Do not use solvents or scratch metallic / 
Teflon
®
 coated surfaces.
5.
Replace cleaned spring, diffuser and lower assembly 
following instructions below or use new replacement 
kit assembly. For correct kit number, see Table 1.
Install spring, diffuser and lower assembly:
A.
Insert spring onto diffuser.
B.
Insert diffuser with spring end first into body.
C.
Fit valve top assembly into lower assembly and insert into valve. 
D.
Tighten lower nut.
E.
Reposition handwheel and insert screw. Turn handwheel to 
desired temperature setting.
Fig. 3. AM-1 Series valves assembly.
Fig. 4. Dimensions in in. (mm).
M23941
LOWER ASSEMBLY
HANDWHEEL
DIFFUSER
SPRING
VALVE BODY
TOP ASSEMBLY
LOWER NUT
UPPER NUT
O RING
RETAINING RING
C
H
MIX
H
Table 1. AM-1 Series Replacement Kits
Model
Temperature Range
Part No.
C
70°–120° F (21°–49°C)
AM-1-020 RP
STD
70°–145° F (21°–63° C)
AM-1-025 RP
M23938
MIX
H
C
B
C
2-1/4 
(57)
A
Ø 1-51/64
(46)