The zone panel is typically installed near the indoor unit, in a garage, crawl space, basement, or attic. Zone panels
are often installed on the return air duct. However, in some heat pump applications, the homeowner or building
occupant may require access to the panel to change
into the emergency heat mode. To meet these needs,
install the panel in a utility closet or other convenient
area where the panel is easily accessed.
Fig. 6. Typical horizontal
Mount and wire a dedicated transformer to the zone panel. The AT140A1042 is rated to 130°F (54°C). If it is to be
mounted in an attic that may get much hotter, install the AT175A1008, which is rated to provide 50 VA at 165°F (74°C).
Connect power to the zone control panel after all other wires are attached.
Variable Speed Fan
A variable speed fan or ECM blower changes blower speed to deliver a constant CFM regardless of static pressure.
To use zoning with a variable speed fan, plan and install zoning normally, and use an SPRD or a MARD (round)
damper with static pressure control (SPC) for bypass.
24 VOLT TRANS.
Fig. 7. Wiring variable speed
fan to TrueZONE panel.
SPRD BYPASS DAMPER
TrueZONE PANEL MOUNTED
ON RETURN DUCT
DATS (AT LEAST 3 FT
FURNACE OR AIR CONDITIONER
Fig. 5. Typical upflow HVAC system.
Install thermostats using instructions
provided with thermostat. Wireless
thermostats can be used to speed
If using a Honeywell TrueZONE panel, the panel's
DS/BK terminal is intended for use with a vari-
able-speed fan. When one zone is calling (or less
than 25% of capacity on systems with more than 4
zones), this terminal will be de-energized of 24 VAC.
This reduces blower speed on most variable speed
Zoning System Design Manual
MOUNTED ON WALL