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T8511G Deluxe Heat Pump

Zone Thermostat

The T8511G Deluxe Heat Pump Zone Thermostat provides electronic control of 24 Vac heat pump zoned systems. Refer
to Table 1 for a general description of the thermostat.
Table 1. Description of T8511 Thermostat.
Model Application Powering Method Changeover System Selection Fan Selection
T8511G Zone 1 on MABS II or
TotalZone® system Requires common wire to
power supply Automatic or
Manual Em Heat-Heat-Off-
Cool-Auto On-Auto


If this control is replacing a control that contains
mercury in a sealed tube, do
place your old
control in the trash.
Contact your local waste management authority for
instructions regarding recycling and the proper
disposal of the old thermostat.
When Installing this Product…
1. Read these instructions carefully. Failure to follow
the instructions can damage the product or 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
4. After completing installation, use these instructions
to check out the product operation.
Install the thermostat about 5 ft (1.5m) above the floor in
an area with good air circulation at average temperature.
See Fig. 1.
Do not install the 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 sun or appliances.
concealed pipes and chimneys.
unheated (uncooled) areas such as an outside wall
behind the thermostat.
Wallplate Installation
The thermostat can be mounted horizontally on the wall or
on a 2 in. x 4 in. wiring box. Position wallplate horizontally
on the wall or on a 2 in. x 4 in. wiring box.
1. Position and level the wallplate (for appearance
only). The thermostat will function properly even
when not level.
2. Use a pencil to mark the mounting holes. See Fig. 2.
3. Remove the wallplate from the wall and drill two
3/16 inch holes in the wall (if drywall) as marked.
For firmer material such as plaster, drill two 7/32 inch
holes. Gently tap anchors (provided) into the drilled
holes until flush with the wall.
4. Position the wallplate over the holes, pulling wires
through the wiring opening.
5. Loosely insert the mounting screws into the holes.
6. Tighten mounting screws.