Installation Instructions

ManualsBrandsSiemens ManualsHeating SuppliesTH-188 Direct/Reverse Acting Thermostat - Unit Mounted

Table Of Contents

Document No. 129-129

September 24, 2009

TH 188 Unit Mounted Thermostats

Item Number 129-129, Rev. 300 Page 1 of 3

Product Description

The TH 188 Unit Mounted Thermostat is a remote

bulb, gradual acting pneumatic instrument that

maintains a preselected room temperature by

positioning pneumatic devices that control heating or

cooling medium. This thermostat has a liquid filled

thermal system.

Product Numbers

TH 188R Reverse Acting (RA)

20 scim (5.5 ml/s) restrictor

188-0024

TH 188HC Heating (direct)/Cooling

(reverse) 40 scim (11 ml/s) restrictor

188-0030

TH 188D Direct Acting (DA)

40 scim (11 ml/s) restrictor

188-0031

Replacement for Honeywell models

LP916BXXXX

Heating (direct)/Cooling (reverse)

40 scim (11 ml/s) restrictor

188-0033

Replacement for Johnson Controls

T-3300-2

Heating (direct)/Cooling (reverse)

40 scim (11 ml/s) restrictor

188-0034

Required Tools

• Medium flat-blade screwdriver

• Small drill

Expected Installation Time

90 minutes (1 hour and 30 minutes)

Installation

A mounting bracket is included for mounting the

thermostat in various units.

1. Fasten the mounting bracket to the partition

with two sheet metal screws included with the

thermostat. Figure 1 shows a typical

installation.

Figure 1. Thermostat and Mounting Bracket.

NOTE: If there is not enough room to mount the

thermostat in a convenient location, or if

the set point dial must be in the same

compartment as the fan switch, order an

extension shaft kit (Part Number 188-101).

See Figure 2.

Using the extension shaft, mount the

thermostat in any convenient location

within eight inches of the control

compartment.

Figure 2. Use of Shaft Extension.

2. Mount the remote sensing bulb in the air stream

of the return air (near the inlet of the fan).

Avoid metal to metal contact between the bulb

and the unit to prevent damage to the soft

copper sensing bulb from unit vibration.

Summary of content (3 pages)

PAGE 1
Installation Instructions Document No. 129-129 September 24, 2009 TH 188 Unit Mounted Thermostats Product Description The TH 188 Unit Mounted Thermostat is a remote bulb, gradual acting pneumatic instrument that maintains a preselected room temperature by positioning pneumatic devices that control heating or cooling medium. This thermostat has a liquid filled thermal system. Product Numbers TH 188R Reverse Acting (RA) 20 scim (5.
PAGE 2
Document No. 129-129 Installation Instructions September 24, 2009 Installation, Continued Dual action 3. Fasten the capillary and/or bulb in the return air stream using the adhesive backed cable clip included in the kit. On the HC thermostat, calibration should be at 7-1/2 psi (52 kPa) for both DA and RA. The unit has one thermal system with a reversing relay to give the action desired. If calibrated at 7-1/2 psi (52 kPa) for winter, the summer calibration will be 7-1/2 psi (52 kPa).
PAGE 3
Document No. 129-129 Installation Instructions September 24, 2009 Heat–cool thermostat changeover Installation, Continued See Table 1 for air pressure and changeover pressure. The changeover is a factory adjustment; it is sealed with ambroid and does not require field adjustment. If, for some reason, this adjustment is disturbed, readjust as follows (See Figure 5): Figure 5. Heating/Cooling Changeover. 4. Rotate adjustment post to give an output within 1/2 psi (3.4 kPa) of calibration pressure. 5.