20
FORM 145.18-IOM1
ISSUE DATE: 8/30/2018
SECTION 1 - INSTALLATION
Optional Disconnect
Optional ADA Molex
Connection
LD27631
FIGURE 10 -
UNIT SWITCH PLATE WITH ADA
THERMOSTAT CONNECTION
Optional ADA Door Mounted Thermostat
For units ordered with the Americans with Disabilities
Act (ADA) thermostat option to meet ADA require-
ments, the thermostat is located on the RA panel door
at a height of 48 inches from the base of the cabinet.
Unit is supplied with a custom RA door panel with
thermostat mounting holes, unit switch plate with a
Molex connector, and an ADA Molex pigtail harness.
See
Acoustic Return Air (RA) Panel on page 20
and
Figure 14 on page 23
.
Wire leads from the ADA thermostat harness are field
wired to thermostat terminals. The Molex end of the
ADA thermostat harness is field connected to the sur-
face mounted Molex connector at unit switch plate.
Mount the thermostat using the factory provided 1/4-
inch number 8 screws. The ADA thermostat harness is
plenum rated. It hangs behind the RA door. For chassis
servicing, unclip harness from unit switch plate.
EC Motor (ECM) Continuous Fan
This option features a factory wired continuous low
speed fan circuit. Because of the five available motor
speed taps, the EC motor (ECM) offers an ideal range
for supporting continuous low speed fan.
The fan runs continuously on the low fan speed setting
even if there is no demand for cooling or heating. The
continuous fan is controlled by a dry contact to provide
interlocking to energy recovery ventilator (ERV) or
room occupancy control. See
Figure 28 on page 46
for electrical schematics.
CLOSET AND DRYWALL INSTALLATION
To avoid potential vibration and noise is-
sues, the RA panel should not contact any
part of the unit cabinet or sleeve. Maintain
a sufficient gap between RA panel frame
and cabinet.
Build a closet enclosure for the cabinet that incorpo-
rates the RA panel size while maintaining a sufficient
gap between the closet and cabinet. This prevents the
cabinet from contacting the RA panel and closet enclo-
sure. Refer to
Acoustic Return Air (RA) Panel on page
20
,
Figure 11 on page 21
,
and
Figure 12 on page
22
.
1. Cover the supply and return openings with plas-
tic or cardboard before installing drywall around
cabinet. This prevents dust or debris from entering
the unit components.
2. Install the drywall using conventional construc-
tion methods. Do not fasten studs or drywall di-
rectly to the cabinet surface. Space the framing
members according to the RA access and the type/
quantity of supply air (SA) outlets. See
Figure 11
on page 21
and
Figure 12 on page 22
.
3. Install sheetrock around unit cabinet by securing
the drywall to the building construction studs.
4. Cut holes around the SA and RA openings to al-
low access to the unit chassis, unit controls, and
the SA connection.
5. Vacuum all dust and construction debris from the
unit drain pan, electrical box, and discharge ple-
num after cutting out the supply/returns openings.
To prevent electrical shorts and drain pan
leaks, DO NOT penetrate unit compo-
nents when driving screws near the unit
control box or drain pan. Do not allow
screws or nails to penetrate chassis, risers,
electrical junction boxes, conduits, or to
interfere with chassis removal.
ACOUSTIC RETURN AIR (RA) PANEL
RA panels are painted standard appliance white. Care-
fully unpack RA panels from their shipping box. RA
panels with optional key locks require the key locks
to be field installed to the slot in the panel door. ADA
RA door panels come with an opening and pilot holes
mounting a thermostat. The ADA harness for wiring
the thermostat and connecting to the unit is shipped
loose with the thermostats.
