Pentax T87F Installation Manual

TRADELINE

T87F

Universal Thermostat

Installation Instructions for the Trained Service Technician.

Application

The T87F Universal Thermostat provides tempera­ture control for 24 to 30 Vac residential heating, cooling
or heating-cooling systems. For heating systems, the
T87F mounts on the wallplate provided. For cooling
only, or heating-cooling, order the 137421A (198170A
if textured designer model) Heating-Cooling Wallplate
with remote switching, or the Q539 Subbase, which
provides switching at the thermostat location.

The spdt switch makes one set of contacts on a tem­perature fall to operate the heating system. The other set
of contacts make on a temperature rise to operate the
cooling system when the T87F is used to control cool­ing.

Heat anticipation is adjustable, 0.1 to 1.2A.

M3375

Mercury Notice

This control contains mercury in a sealed tube. Do not
place control in the trash at the end of its useful life.

If this control is replacing a control that contains
mercury in a sealed tube, do not place your old control in
the trash.

Contact your local waste management authority for
instructions regarding recycling and the proper disposal
of this control, or of an old control containing mercury in
a sealed tube.

If you have questions, call Honeywell Inc. at 1­800-468-1502.

Installation and Setting

WHEN INSTALLING THIS PRODUCT…

1. Read these instructions carefully. Failure to fol-

low them could cause a hazardous condition.

2. Check the ratings given in the instructions and on
the product to make sure the product is suitable for your
application.

3. Installer must be a trained, experienced service
technician.

4. After installation is complete, check out product
operation as provided in these instructions.

CAUTION

1. Disconnect power supply to prevent electri­cal shock or equipment damage.

2. To prevent interference with the thermostat
linkage, keep wire length to a minimum and
run wires as close as possible to the subbase.

3. Do not overtighten thermostat captive mount­ing screws because damage to subbase threads
can result.

4. Do not short across coil terminals on relay.
This can burn out the thermostat heat antici­pator.

IMPORTANT: An incorrectly leveled thermostat will

cause the temperature control to deviate from set
point.

LOCATION

Install the thermostat about 5 ft [1.5m] above the
floor in an area with good air circulation at average
temperature.

Do not install the thermostat where it may be affected
by:

— drafts, or dead spots behind doors and in corners.

— hot or cold air from ducts.

— radiant heat from sun or appliances.

— concealed pipes and chimneys.

— unheated (uncooled) areas such as an outside wall

behind the thermostat.

This thermostat is a precision instrument and was
carefully adjusted at the factory. Handle it carefully.

MOUNTING WALLPLATE OR SUBBASE (Fig. 2)

IMPORTANT:

1. Use a spirit level to accurately level the wallplate
or subbase as in Fig. 1. Inaccurate leveling may
cause thermostat control deviation.

2. When using the T87F with a Q539 Subbase, follow
the mounting and wiring instructions included with
the subbase.

1. Place the wallplate on the wall at the desired loca-

tion. Pull the thermostat cable through the entrance hole.

2. Fasten wallplate. Do not tighten the screws.

3. Level according to Fig. 1 then tighten screws.

4. After wiring wallplate, plug hole to prevent drafts

from affecting thermostat.

NOTE: To mount T87 Thermostat on an outlet box,

order 129044A Adapter Ring Assembly.

®U.S. Registered Trademark
Copyright © 2002 Honeywell • • All Rights Reserved

60-0830-4

Fig. 1—Leveling wallplate or subbase with
spirit level or plumb line.

SPIRIT
LEVEL

OPENING FOR
THERMOSTAT
WIRING

LEVELING
POSTS (2)

MOUNTING
SLOTS

M3319A

Fig. 2—Mounting wallplate or subbase to wall.

COVER RING

MOLDED
LEVELING
POST

WALLPLATE
SHOWN

THERMOSTAT CABLE
ENTRANCE HOLES

NO. 4 X 1 INCH
SHEET METAL SCREWS (2)

WIRING

All wiring must comply with local electrical codes
and ordinances. Disconnect power supply before con­necting wiring to prevent electrical shock or equipment
damage.

The T87F is adaptable to most 2-wire, 24 to 30 volt
heating systems, and to most 3-wire, 24 to 30 volt
heating systems controlled by a Series 10 Thermostat.
The following hookups are typical applications. See
Figs. 3 through 7. When using the T87F for cooling
control, refer to the hookups in the Q539 Subbase in­structions.

For variations of these systems, refer to the installa­tion instructions for the controlled equipment.

After wiring the wallplate, plug the hole to prevent
drafts that may affect the thermostat.

ADD T87F AS
SHOWN ON OUTLET
BOX MOUNTING

M5324

Fig. 3—T87F used for 2-wire, spst control of
heating only in a typical oil system. Low
voltage power for the control circuit is supplied
by a transformer in the oil primary control.

COMBINATION

L1 (HOT)

FAN AND LIMIT

L2

137421A
WALLPLATE

TR

TRTH

CONTROL

BURNER
MOTOR

T

T

F

F

IGNITION

R8184G

WHITE

2

ORANGE

BLACK

TRANSFORMER

B

W

R

OIL VALVE

COMBINATION
FAN AND LIMIT
CONTROL

FAN

LIMIT

JUMPER

B

W

R

FAN
MOTOR

3

M6105

1

FAN
MOTOR

M5318

TO THERMOSTAT
CONNECTIONS ON
SERIES 10 VALVE
AT BURNER

M6102

1

THERMOSTAT

Y

R

W

CAD
CELL

POWER SUPPLY. PROVIDE DISCONNECT MEANS AND

1

OVERLOAD PROTECTION AS REQUIRED.

R8184 PROTECTORELAY OIL PRIMARY CONTAINS

2

INTERNAL TRANSFORMER.

3

CONNECT OIL VALVE, IF APPLICABLE.

Fig. 4—T87F used for 2-wire, spst control of
heating only in a typical gas system.

Y

R

W

GAS VALVE

TH

1

POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.

Fig. 5—T87F replacing a Series 10 Thermostat
connected to a 3-wire, open-contact, high-limit
control.

LOW LIMIT
OPERATING CONTROL

T87F

Y

R

W

SERIES 10 OPEN
CIRCUIT HIGH LIMIT

L1
(HOT)

L2

60-0830—4 2