GPGM3 Installation Manual
12
NOTE:
DO NOT use gas piping, or conduit as an electrical ground.
Low voltage wiring from the unit control panel to the ther-
mostat requires coded cable. See below for ground level
and rooftop wiring.
-
-
Connect incoming power leads to terminals L1 & L2 on
contactor in the electrical control section, using wire sizes
BRANCH CIRCUIT AMPACITY
15 20 25 30 35 40 45 50
SUPPLY WIRE LENGTH -
FEET
200 6 4 4 4 3 3 2 2
150 8 6 6 4 4 4 3 3
100 10 8 8 6 6 6 4 4
50 14 12 10 10 8 8 6 6
CIRCULATING AIR AND FILTERS
Units can easily be converted from horizontal to down-dis-
installations, the installer should measure the total external
static and review the blower performance charts before
performing the installation. In some installations it will be
necessary to change the blower speed to provide proper
Horizontal Air Flow
Cut insulation around bottom openings and remove panels
from the bottom of the unit, saving the screws holding the
panels in place.
-
Duct systems and register sizes must be properly designed
for the C.F.M. and external static pressure rating of the
unit. Ductwork should be designed in accordance with the
recommended methods of Air Conditioning Contractors of
-
weatherproof barrier and adequate insulation.
A duct system should be installed in accordance with
Standards of the National Board of Fire Underwriters for
the Installation of Air Conditioning, Warm Air Heating and
The supply duct from the unit through a wall may be installed
without clearance. However, minimum unit clearances as
shown in the appendix must be maintained. The supply duct
should be provided with an access panel large enough to
inspect the air chamber downstream of the heat exchanger.
A cover should be tightly attached to prevent air leaks.
Dimension illustration in the appendix.
For down-discharge applications, the ductwork should
be attached to the roof curb prior to installing the unit.
Ductwork dimensions are shown in the roof curb installa-
tion manual.
If desired, supply and return duct connections to the unit
unit operating sound transmission.