Model ST series panels are for single stage heating and cooling
with manual changeover. Zone 1 is the "master" zone which controls the
heating and cooling mode and also the fan operation. The ST-2 is a 2 zone panel and
the ST-3 is a 3 zone panel. Zones 2 and 3 will only operate in the same mode that
the zone 1 thermostat is in. Each thermostat can turn the system "on" and
"off ", but only in the same mode. It is recommended the zones 2 and 3
have no switching subbases for the thermostats. The ST panels can be used with
mechanical or digital programmable thermostats that are non-power stealing.
Open-Close switches on the control panels near the damper terminal blocks allow for
continuous air circulation. This switch controls the damper position when the
heating and air conditioning system is at rest. The ST panels can be wired together
to create larger zoning systems up to 6 zones.
