Honeywell MP953D Instruction Manual

IB-52
Installation and Maintenance
REPAIR AND ADJUSTMENT PROCEDURES FOR HONEYWELL MP-953B, MP-953D,
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 MP-953B, MP-953D,
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
CT,OSED 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 MP-953D, 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.)

36
,
36
34 ?* 3g
““\ 23
37
\
Ad -
y-p
\
‘\
L
. _-
--
33
- I
14

AND ADJUSTMENT PROCEDURES FOR HONEYWELL MP-953B, MP-953D,
OR MP-953F PNEUMATIC OPERATORS USED ON ARNSTRONG HUMIDIFIERS
II.
INSTALLING THE PNEUMATIC OPERATOR
After necessary repairs have been made, perform the
following steps to install the operator.
1.
2.
3.
4.
5.
6.
7.
a.
9.
10.
Press down the valve stem (16) so
that the valve is
completely
closed.
_Stem Adapter
If the stem nut (17) and stem
,Stem Nut
adapter (17A) were not removed 3-i/2"*
--.__ ---Stem
during repairs, check
the
adjustment shown
in Figure 2.
Adjust as required.
_Matinq surface
If the stem nut (17) and stem
for Operator
adapter (17A) were removed during
-Humidifier
repairs,
turn them onto the stem
and adjust as shown in Figure 2.
*With valve in closed position
Assemble the yoke assembly (36) and
Figure 2.
stem adapter (17A) in the following
manner.
4
Hold the bearing (36B) in the orientation shown in
Figure 1 (flat side down, depression up).
Slide
the bearing into the groove of the stem adapter
(17A).
b)
Place the spring (36C) on top of the stem adapter
(17A) and bearing
(36B) with the longer tabs
pointed downward toward the notches in the sides
of the bearing.
c)
Slide the yoke (36A) over the spring (36C),
bearing (36B),
and stem adapter (17A) until the
short tabs of the spring snap into place on both
sides of the yoke.
Center the yoke over the stem
(16) l
Place the operator over the yoke assembly (36) and
lower the operator onto the bonnet (15).
Hold the operator to prevent it from turning. Insert a
screwdriver into the slot in the top of the yoke (36)
and turn counterclockwise until the operator base (26)
contacts the mating surface of the bonnet (15).
Tighten th.e two set screws (27).
Load the stem by turning the yoke (36) clockwise until
the spring cup (28) is from l/16 to l/8 inch above the
operator base (26).
(Dimension "A" in Figure 1).
Install the operator plug (35) in the top of the MP-
9530 or close the access plate on the top of the MP-
953B or MP-953F.
Turn on the steam to the humidifier.
Connect the air line to the operator and turn on the
instrument air. Make any necessary adjustments.
2

REPRAIR AND ADJUSTMENT PRC%EDURES FOR HONEYWELL MP-953B, M%-95iD,
OR MP-953P PNEUMATIC OPERATORS USED ON ARMSTRONG HUHIDIFIERS
.---,
III. REPLACING STEM SEALS
There are stem seals in the bonnet assembly to prevent steam
leaks around the stem. The following steps should be
followed if these seals need to be replaced.
1.
2.
3.
4.
5.
6.
7.
a.
9.
10.
Remove the pneumatic operator in accordance with
Section I.
Remove the bonnet assembly (15) from the humidifier
cap.
Remove the yoke assembly (36), stem adapter (17A), and
stem nut (17) from the stem (16).
Remove the packing gland (18) from the bonnet (15).
Push down the valve stem (16), then press it back into
place.
Repeat if necessary to loosen the seals (20)
and spacer (19).
Remove the seals (20) and spacer (19).
With the stem (16) in the bonnet (15), place two new
seals (20) with the spacer (19) between them, onto the
stem. The open end of BOTH seals (with spring showing)
should be toward the valve.
Carefully guide the seals into place in the bonnet
(15).
Slide the packing gland (18) over the stem and
turn it into the bonnet.
Tighten the packing gland
securely.
Turn the bonnet assembly (15) into the humidifier cap,
and tighten securely.
Install the pneumatic operator in accordance with
Section II.
IV.
CHANGING OPERATOR SPRlNGS
1.
2.
3.
4.
5.
6.
7.
a.
9.
10.
Remove
the pneumatic operator in accordance with
Section I.
Remove the six cover screws (31) from the operator
cover (33).
Lift the cover (33) from the frame (29).
Remove the hex nut (34) and washer (32) from the
support (24).
Remove the follower (38) and diaphragm (21) from the
frame (29).
Invert~the operator and remove the screws (25) from the
base (26).
Remove the base (26).
Carefully remove the cup (28) and support (24) -- avoid
damaging the rolling seal (22).
Remove the old spring (30) and replace it with the new
one.
Insert the support (24) through the center of the cup
(28), and place the support and cup into the operator
frame.
Attach the rolling seal (22), and press the ‘i/
support back into place.
3

.^____ -----
‘- Bb
b&REPAIR AND ADJUSTMENT PROCEDURES FOR HONEYWELL MP-953B, MP-953D,
OR MP-953F PNEUMATIC OPERATORS USED ON ARMSTRONG HUMIDIFIERS
11.
12.
13.
14.
15.
16.
Place the operator base (26)' onto the frame (29), and
secure it in place with screws (25).
Invert the operator back to its upright position.
Place the diaphragm (21) and follower (38) into the
frame (29).
Place the washer (32) around the top of the support
(24), and turn on the nut (34). Tighten securely.
With outer edge of the diaphragm (21) in the groove of
the frame (29), place the cove-r (33) over the frame.
Align the screw holes.
Attach the cover with the cover screws (31). Tighten
securely.
Install the -pneumatic operator in accordance with
Section.11.
V.
CHANGIN G THE ROLLING SEAL
To
1.
2.
3.
replace a rolling seal, perform the following steps.
4.
5.
6.
7.
8.
Remove the pneumatic operator in accordance with
Section I.
Perform Section IV (CHANGING OPERATOR SPRINGS) steps 2
through 8 to disassemble the operator.
With the operator in the upright position, remove the
three screws (23) and ring (39) that secure the rolling
seal (22).
Remove the rolling seal (22). Then separate the cup
(37) from the old seal.
Place the cup (37) into the new rolling seal.
Install
the new seal in the frame.
Secure the new rolling seal (22) in place with the ring
(39) and three screws (23). Tighten securely. Be sure
that the edge of the rolling seal is in the groove in
the frame.
Perform Section IV steps 10 through 15 to reassemble
the operator. Be sure that the spring (30) is in
place.
Install the pneumatic operator in accordance with
Section II.
VI.
REPLACING THE HUMIDIFIER VALVE AND SEAT
To replace the humidifier valve and seat, perform the
following steps.
1.
Remove the pneumatic operator in accordance with
Section I.
2.
Remove the bonnet assembly (15) from the humidirier
cap.
4

9
‘h_
iii
b&REPAIR AND ADJUSTMENT PROCEDURES FOR HONEYWELL MP-953B, MP-953D,
OR MP-953F PNEUMATIC OPERATORS USED ON ARMSTRONG HUMIDIFIERS
3.
Using a socket wrench, remove the old valve seat (14
from the humidifier cap. Install a new valve seat in
its place.
4.
Remove the yoke assembly (36), from the stem (16).
5.
Remove the old valve and stem assembly (16) from the
bonnet,
and replace with a new valve and stem assembly.
NOTE:
If the stem seals are worn, replace them by
performing Section III (REPLACING STEM SEALS), steps 4
through 8.
6.
Install the bonnet assembly (15) in the humidifier cap,
and tighten securely.
7. Install the pneumatic operator in accordance with
Section II.
VII. CHANGING THE DIAPHRAGM
To replace the diaphragm, perform the following steps.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Turn off the steam to the humidifier.
Turn off the instrument air to the operator.
NOTE:
Generally,
the diaphragm is replaced without
removing the operator from the humidirier.
However,
there are times that the location of the humidifier
'-
makes it more convenient to remove the operator to a
workbench for repair.
Remove the six cover screws (31) from the operator
cover (33).
Lift the cover (33) from the frame (29).
Remove the hex nut (34) and washer (32) from the
support (24).
[Do not disturb the yoke assembly (36).]
Remove the follower (38) and diaphragm (21) from the
frame (29).
Discard the old diaphragm (21) and lay a new one in its
place.
Place the follower (38) on the diaphragm. Then place
washer (32) around the top of the support (24), and
turn on the nut (34). Tighten securely.
With the outer edge of the diaphragm (21) in the groove
of the frame (29), place the cover (33) over the frame.
Align the screw holes.
Install and tighten the six cover screws (31).
Turn on the steam to the humidifier.
Turn on the instrument air to the operator.
NOTE:
THE FOLLOWING ADJUSTMENTS ARE NECESSARY ONLY FOR
THE GRADUTROL RELAY USED WITH THE MP-953B OPERATORS‘AND
WITH MP-953F PILOT POSITIONERS.
5

b&REPAIR AND ADJUSTMENT PROCEDURES FOR HONEYWELL MP-953B, MP-953D,
1)
MP-953F PNEUMATIC.OPERATORS USED ON ARMSTRONG HUMIDIFIERS
VIII.OPERATING RANGE AND START POINT
- MP-953B (See Figure 3)
1.
Using a wrench (Honeywell Part No. 301572A supplied
with gradutrol), loosen the cover locking screw.
2.
Unscrew the start point adjustment knob and make
adjustments according to the directions printed inside
IX.
the knob as follows:
Range adjustment -
a)
3 lb. range, all
screws backed
off
to friction stop.
b)
5 lb. range, plated
(outer) screws
tightened. Black
(inner) screws
backed-off to
friction stop.
c)
10 lb. range, all
screws tightened.
Start point adjustment -
a)
b)
cl
Tighten cover until
it bottoms.
Back off (one turn
max.) until desired
start point of
correct range scale
lines up with
indicator near
11 B"
marking.
Tighten the cover locking screw until it engages
the relay housing. Do not overtighten.
OPERATING
1.
Set
2.
S
c
TART POINT
iDJUSTMENT
COVER RANGE ADJUSTMENT
,,r,nn
LOCKING
hlY”D
/SCREW
SCREWS
RANGE ADJUSTMENT
(BLANK)- (3)
SCREWS
RELA; BODY
Fig. 3 -
Adjustment Points of
Gradutrol Relay.
START
3R
RANGE AND START POINT
- MP-953F PILOT POSITIONER
the start point on the positioner to the value
desired.
Each click of the start point knob adjusts
the start point l/4 psi.
NOTE:
ON THE MP-953F PILOT POSITIONER, ONLY THE START
POINT IS ADJUSTABLE. THE SPRING RANGE IS NOT
ADJUSTABLE.
THE RANGE CAN ONLY BE CHANGED BY REPLACING
THE FEEDBACK SPRING.
Honeywell MP-953F operators (with positioners) come
standard with an 8 -
13 psi (black) main spring. This
soring does us& mge. The feedback spring, however,
maybe changed in order to vary the spring range of the
operator.
It is available in 3
(See Chart 4)
,\-5, or 10 lb. ranges.
Since the start point is adjustable,
full open point willbethe startpointplus the spring
range.
6

--T-
9
,$$ AREPAIR AND ADJUSTMENT PROCEDURES FOR HONEYWELL MP-953B, MP-953D,
lb
MP-953P PNEUMATIC OPERATORS USED ON ARMSTRONG HUMIDIFIERS
x.
Feedback springs are available in a kit containing:
l- Bias Spring
l-
White feedback spring, operating range 3 psi
1 - Bronze feedback spring, operating range 5 psi
1 - Violet feedback spring, operating range 10 psi
3.
To change the feedback spring:
:;
Turn off the instrument air.
Remove the pilot positioner by removing the two
phillips head screws and one cover screw.
Do not
remove the pneumatic tubing.
c)
The feedback spring is located in the operator on
top of the main diaphragm. Remove the old
feedback spring.
d)
Insert
the feedback spring that will give the
desired operating range.
Replace the bias spring
located on top of the operator.
e)
Replace the pilot positioner.
f)
Turn on the instrument air.
ADJUSTMENT CHECK
(MP-953B AND MP-953F MODELS ONLY)
1.
Install guages in the main and pilot air lines.
2. Main air pressure should be equal to or more than top
of sequencing range: 13 psi is minimum main pressure
for device to function.
3. Slowly apply pilot pressure and note the pressure at
which valve stem travel starts. This pressure should
be within + 3/4 psi for the B model (+ 1 psi for the F
model) of the start point setting.
4. Slowly increase pilot pressure until valve stem travel
is complete. This pressure should be within + 3/4 psi
for the B model (+lpsi for the F model) of the start
point pressure plus the range setting.
5 Make fine adjustments, if necessary, with the start
point adjustment knob. CAUTION (B MODEL ONLY): Loosen
the cover locking screws before turning the start point
adjustment knob.