Electric heat installation, Wdg air handler series – Comfort-Aire WDG Air Handler Series User Manual
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Installation, Operation & Maintenance
WDG AIR HANDLER SERIES
Heat Controller, LLC
Locate electric heat assembly
on pins in discharge panel
and insert screws
Relocate blower in electric
heat assembly in same
manner
Overview
The HG Series Auxiliary Electric Heat mounts internally in
upfl ow (Figures 10-12) or downfl ow units and horizontal units.
Horizontal units are rated for zero clearance at the unit and 1"
clearance for fi rst three feet of duct, vertical units rated for zero
clearance for both unit and duct. Downfl ow units can not be
located directly over a discharge register. The discharge plenum
must be constructed from non combustible material. The HG
electric heat contains a four stage relay control board which
activates the elements directly via an internally wired low voltage
harness. Low voltage signals (W1 and W2) are staged from the
DXM2 control.
Vertical Upfl ow or Downfl ow and Horizontal Installation
1. Disconnect power to the unit
2. Remove blower access panels.
3. Clip wire-tie holding electric heat low voltage 3-wire harness
to discharge panel stiffener.
4. Remove blower mounting screws and then drop down
blower assembly as shown in Figure 11. Removal of blower
wires should not be necessary.
5. Install electric heat in discharge fl ange where blower
assembly has been removed using provided screws as
shown In Figure 12.
5.5 For downfl ow or horizontal right discharge units, the air
handler support bracket must be removed to re-install the
blower housing assembly. After re-installing the blower
housing, re-install the air handler support bracket.
6. Re-install blower assembly, Figure 12, into electric heat
assembly using blower mounting screws. Check blower
wiring for proper wiring connections.
7. Route the low voltage harness through the provided ‘pie’
bushing and plug into electric heat control board connector
P2 as shown in Figure 18.
8. Install power conduit through unit corner post knockout and
attach conduit directly to the electric heat control box.
9. Optional: HG**C kits only. Blower power may be supplied
from T3 & T4 CB5 breaker. Refer to WDG wiring diagram
96B0005N58.
Electric Heat Installation
Figure 11: Blower removal
Figure 12: HG electric heat mounting and
blower re-installation
Figure 10: Typical air handler installation
Route condiut thru cabinet and
connect to electric heat control
box. Seal to eliminate air leaks on
cabinet exterior.
Low voltage control
harness is prewired
on all distributor class units.
Electric Heat
Assembly
Auxiliary electric heat
power supply knockout
opposite air coil
Disconnect (optional
refer to local code)
Air Coil