IB-52
Installation and Maintenance
REPAIR AND ADJUSTMENT PROCEDURES FOR HONEYWELL
OR MP-953F PNEUMATIC OPERATORS USED ON ARMSTRONG HUMIDIFIERS
This bulletin should be used by experienced personnel as a
guide to the repair and adjustment of Honeywell
or MP-953F pneumatic operators for Armstrong humidifiers.
Selection or installation of equipment should always be
accompanied by competent technical assistance.
We encourage you
to contact Armstrong or its local representative if further
information is required.
WARNING:
BE SURE THAT STEAM SUPPLY VALVE FOR THE HUMIDIFIER IS
BEFORE ATTEMPTING TO MAKE ANY REPAIRS TO THE
OPERATOR.
Maintenance procedures for the Honeywell pneumatic operator
include:
removing the operator from the bonnet, installing the
operator on the bonnet, replacing steam seals, changing operator
springs,
replacing the diaphragm, replacing the rolling seal, and
replacing the valve and seat.
I.
REMOVING THE PNEUMATIC OPERATOR
Many repair procedures require that the operator be removed
from the bonnet assembly.
To remove the operator, perform
the following steps.
Refer to Figure 1 (see back cover) to
locate the parts by item numbers.
1.
Turn oft steam to the humidifier.
2.
Turn off the instrument air and disconnect the line
from the operator.
3.
Loosen the two set screws (27) on both sides of tne
operator base (26).
4.
Remove operator plug (35) from the
or open the
access plate on the MP-953B or MP-953F.
5.
Insert a screwdriver into the slot at the top of the
yoke assembly (36).
Hold the operator and turn
screwdriver
clockwise until the yoke assembly
disengages from the operator.
6.
Lift the operator from the bonnet.
(See Figure 1 on back cover.)
