INSTALLATION INSTRUCTIONS FOR THE TRAINED SERVICE TECHNICIAN
and subbases provide 24 to 30 Vat control for two-stage
heating and one-stage cooling heat pump
systems as follows:
Automatic (Heat or Cool)
On a two-heat
the two stages of heat
as the temperature
refers to the mercury switch initiating a call for heat or
There is about 2 F [1 .I C] between stages so that the
second stage (auxiliary heat) makes only when the first
the load. This is the interstage
Three LEDs (light-emitting
diodes) are included on the
subbase. The red CHECK LED lights when something
needs to be checked
or done to maintain
of the system.
to find out specifically what the CHECK LED
signifies. The green LED lights when the AUX. HT. stage
(second stage) heat is operating. The red EM.HT. LED
lights when the EM.HT. relay is energized,
operating electric strip heaters.
WHEN INSTALLING THIS PRODUCT.
1. Read these instructions
carefully. Failure to follow
them could damage the product or cause a hazardous
2. Check the ratings given in the instructions
the product to make sure the product is suitable for your
3. Installer must be a trained, experienced
4. After installation
check out product
operation as provided in these instructions.
power supply to prevent electrical
shock or equipment damage.
2. Run wires as close to the subbase as possible.
with the thermostat
linkage, keep wire length to a minimum. Push
excess wire back into the hole, and plug hole to
3. Do not overtighten thermostat captive mounting
as damage to subbase threads
4. Do not short across coil terminals on relay. This
may burn out the heat anticipator.
an area with good circulation at average temperature.
Do not install
it may be
or cold air from ducts.
heat from sun or appliances.
pipes and chimneys.
mostat, such as an outside wall.
The thermostat subbase can be mounted on a vertical
outlet box, horizontal outlet box, or directly on the wall.
1. If you must mount the subbase on a vertical outlet
(Fig. 1). The
assembly includes an adapter ring, two screws, and a
cover plate to cover marks on the wall. Install the ring and
cover plate on the vertical outlet box
on outlet box.
@Ho"eyweli Inc. 1986