Honeywell TP975A, TP975B Installation Instructions

TP975A and B

Diffuser

Thermostat

Installation Instructions

Before Installation

1.Install TP975A and B Diffuser Thermostat in accordance with job drawings.

2.Mount units with fixed minimum outdoor air dampers such that the thermostat does not see any outdoor air.

Installation

General

Mounting

The TP975 Diffuser Thermostat is designed to provide proportional control for pneumatic valves and mixing boxes in heating or air conditioning systems. It is a one-pipe thermostat which mounts in one end of a slot or light troffer diffuser; or in a return air grille. Air connection is a sharp barb fitting for 5/32 plastic tubing. The TP975 is factory calibrated, however, field calibration is possible. The proportional band (TR) is adjustable from 2 to 1OF.

The TP975A is direct acting while the TP975B is reverse acting. Normal main line pressure is 18 psig .

PROPORTIONAL

BAND ADJ. (TR)

SETPOINT

ADJ. LEVER

R974

Fig. 1. TP975 with Setpoint Lever in Vertical Position.

The thermostat can be mounted in a variety of positions in fan coil units, return air grilles (wall or ceiling) or in a plenum return The setpoint lever of the TP975 can be rotated 90 degrees to line up in two different mounting planes,

NOTE: On fan coil units it is not recommended to apply a return air thermostat to a unit with a 100 percent outdoor air damper interference and the probability of reducing air flow across the thermostat.

R973

Fig. 2, TP975 with Setpoint Lever in Horizontal Position.

95-7152

Copyright © 1973 Honeywell Inc. All Rights Reserved

MLF TAB: ll.C.2.a.

TOP GRILLE

MOTOR CONTROL

AND JCT BOX

		PIPING	- O P E N I N G F R O N T
PIPING
		OPENING
OPENING	LOCATE PER
\

HOLES	8-32 x3/8 (MAX)
MIN

4070

Fig. 3. Mounting in a Typical Fan Coil Unit.

2