Honeywell RP972A Notice D'installation

DESCRIPTION
The RP972A Reversing Relay is a four-port, modulating
relay suitable for all types of heating and air conditioning
control systems. It is used as a reversing relay to reverse
and increase the capacity of branchline pressure to the
final control element. It has three distinct, detented, field-
adjustable and reversing settings.
See Fig. 1 for approximate dimensions.
1-1/2
(38)
Fig. 1. RP972A dimensions in in. (mm).
INSTALLATION
Mounting
Suspend on tubing or mount on a surface. See Fig. 2. for
surface mounting.
WALL OR
PANEL
RELAY
Fig. 2. Typical surface mounting.
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Copyright © 2002 Honeywell • All Rights Reserved
4
1
2
2-14
(57)
NO. 10 X 1/2 IN.
SHEET METAL SCREW
(OBTAIN LOCALLY)
14003030-001
MOUNTING CLIP
(PROVIDED ON
SOME MODELS)
RP972A Pneumatic
Reversing Relay
Piping
Fig. 3 shows adaptation piping. Port 1 (Main, Supply)
sharp barb for 1/4-in. (6 mm) O.D. tubing. Ports 2, 3, and
4 (Branch, Output; Pilot, Input; and Exhaust,
respectively), sharp barb for 5/32-in (4 mm) O.D. tubing.
CAUTION
Equipment Damage Hazard.
To prevent damage to the sharp barb
connections, do not attempt to cut or pull tubing.
To remove the tubing from the barb connections,
cut tubing a few inches from the control device.
Use a coupling to reconnect tubing.
NOTE: When the system is other than copper or poly-
ethylene tubing, adapt as shown in Fig. 3. Some
models provide the parts for adapting.
3
Port Identification Table
C4860
The two right columns in Table 1 identify the ports on
older Honeywell pneumatic relays when upgrading the
installation.
Pilot
Main
Output
Exhaust
Adjustments
The slotted plunger on the narrow end of the RP972A
Relay is a screwdriver-adjustable bayonet lock. See
Fig. 4. The lock can be set at one of three positions: A, B
or C. Each position provides a different value for "K" in
the following equation.
C8122
INSTALLATION INSTRUCTIONS
Table 1. Pneumatic Relay Ports.
RP972A RP95B
3 1
1 2
2 3
4 —
RP904B
P
M
B
—
95-7148EF