Quick Start Manual
19
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










