Carrier Moduline 37HS Series - Constant Volume Control Installation Details; Constant Volume Control Installation Steps; Shim Removal from Volume Controller; Variable Air Volume Applications Control Installation

Variable Air Volume Applications
1. Remove the plugs from the high-pressure and low-
pressure ports located at the control block of the unit.
2. Remove cap from bellows fitting and install
11
⁄ 16 -in. long
piece of
1
⁄ 4 -in. OD pneumatic adaptor tubing onto the bel-
lows fitting (push on full length of fitting). See Fig. 28.
3. Push the diffuser baffle into the space between side dif-
fusers and down onto the center diffuser at the end away
from the unit. Then push down the end close to the unit.
The baffle will form around the legs of the diffuser spacer
and lock onto the center diffuser. See Fig. 29.
4. To prepare the control filter for installation, be sure that
the bellows chamber filter plug is pushed tightly into the
correct connection. Figure 30 shows the connection ports
on both sides of the filter. The lower bellows port on the
unit side and the small slave bellows pressure connection
on the control side should be capped or plugged before
installation. Moisten the 2 O-rings with water, then push
the filter into the unit end block until the standoffs rest on
the unit end plate. See Fig. 31.
5. 37HS2 and 37HS4: The VAV control packages are shipped
with the diffuser thermostat and volume controller con-
nected by a flexible offset tube. Verify that the offset is in
the correct direction. See Fig. 36.
a. Remove cap from thermostat port of volume control-
ler. See Fig. 32. Pull shim down until released from
thermostat port and then pull shim out from volume
controller body. See Fig. 33. Discard shim.
b. Refer to Fig. 35. Moisten the O-rings of the volume
controller with water and push the controller directly
into the filter.
c. Push the thermostat down onto the center diffuser.
d. Snap spring clip over thermostat and onto the side dif-
fusers to hold thermostat in place. See Fig. 37. Make
sure that thermostat lever will rotate.
e. Remove cap from the aspirator supply port on the unit
end block. Connect the aspirator supply tube to the end
block connection.
S
O
CFM
120
100
80
40
%
ADJUSTMENT
LABEL
INDICATOR
SHIM
THERMOSTAT
PORT
CAP
Fig. 32 — Setting Maximum Volume
(37HS Controller)
Fig. 33 — Shim Removal
LOW-PRESSURE
PORT
FILTER BELLOWS
CONNECTION
VOLUME
CONTROLLER
THERMOSTAT
PORT
CAPPED
HIGH-PRESSURE
PORT
Fig. 34 — Constant Volume Control
Installed on Unit
Fig. 35 — 37HS Control Connections
23