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 for
textured designer model) Heating-Cooling Wallplate with
remote switching, or the Q539 Subbase that 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 makes on a temperature rise to operate
the cooling system when the T87F is used to control
Models with positive Off feature break the electrical
circuit to prevent system operation when the switch is
moved to the Off position. These models use the
137421B Wallplate for cooling or heating/cooling
Heat anticipation is adjustable, 0.1 to 1.2A.
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.
INSTALLATION AND SETTING
When installing this Product...
1. Read these instructions carefully. Failure to follow
them could damage the product or cause a hazard-
2. Check the ratings given in the instructions and on
the product to make sure the product is suitable for
3. Installer must be a trained, experienced service
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T87F Universal Thermostat
• All Rights Reserved
4. After installation is complete, check out product
operation as provided in these instructions.
The T87F was carefully adjusted at the factory.
Handle the thermostat carefully; rough handling
can decrease its accuracy.
Electrical shock can cause personal injury or
Disconnect power supply before beginning
Equipment Damage Hazard.
Causing terminal shorts can burn out heat
Do not short across relay coil terminals.
Select a location about 1.5m (5 ft) above the floor in an
area with good air circulation at average temperature.
Do not mount thermostat where it can be affected by:
— drafts or dead spots behind doors and in corners.
— hot or cold air from ducts.
— radiant heat from the sun or appliances.
— concealed pipes and chimneys.
— unheated (uncooled) areas behind the thermostat.
Mounting subbase wallplate (Fig. 2)
1. Use spirit level to accurately level the wallplate
or subbase; see Fig. 1. Inaccurate leveling can
cause thermostat control deviation.
2. When using the T87F with a Q539 Subbase, fol-
low the mounting and wiring instructions
included with the subbase.
1. Place wallplate on wall at desired location. Pull
thermostat cable through entrance hole.
2. Fasten wallplate but do not tighten screws.