I n s t a l l a t i o n , O p e r a t i o n , M a i n t e n a n c e
48
W A T E R - S O U R C E H E A T P U M P S
Under extreme circumstances this procedure may be
required multiple times to purge all air from the circuit.
After completing the flushing/purging procedure, recon
-
nect the red wire to the ACC1 ‘N.O.’ terminal on the
DXM2 for normal operation. Reconnect the white sen-
sor wire to the P10 terminal block of the DXM2 control
board, as described in Figure 20 below. If air is allowed
to collect in the condenser hot water reheat piping, nui-
sance trips may occur. Additional flush/purge cycles may
be used when required.
JE-Series
I s s u e D a t e :
M a y 1 0 , 2 0 2 1
Flushing/Purging Units with Condenser Hot Water Reheat
When flushing/purging units equipped with condenser
hot water reheat the unit should be fully flushed/purged
before attempting to flush/purge the condenser hot water
reheat coil. Once the unit is flushed, energize the mod
-
ulating three-way dehumidification valve to allow flow
through the condenser hot water reheat hydronic circuit.
The unit must be powered (but not operating) during
flushing/purging. Unit power is required to operate the
three-way modulating valve during flushing.
Disable the condenser hot water reheat
sensor located
in the supply air stream by removing the white wire
from the P10 terminal strip located on the DXM2 con-
trol board, as described below in Figure 20. Energize the
modulating three-way dehumidification valve by remov
-
ing the red wire from the ACC1 ‘NO’ terminal on the
DXM2 control board, and connect it to the ACC1 ‘NC’ ter-
minal as shown in Figure 21. Once energized, the valve
will take 45 – 75 seconds to fully shift. Continue flushing
during this time. After the valve has completed its shift,
use the air bleed from the top of the reheat coil to purge
air from the coil.
De-energize the valve by removing the red wire from the
ACC1 ‘NC’ terminal on the DXM2 board. The valve will
spring return to its normal position in just a few seconds.
After the valve has fully returned, repeat the process of
running the valve through its cycle and purging air from
the reheat coil.
BLK
BLK
CDT
BRN
BRN
EW
T
LW
T
LAT
GRN
YEL
WHT
PII
PI0
P9
CC
A0-I
G
ND
G
ND
A0-2
TI
T2
T2
T3
T3
T4
T4
T5
T5
T6
T6
Figure 20: LAT Sensor Connection to P10 Terminal Strip
R
N0I
NCI
COM
N02
NC2
COM
R
RELAY
ACC2
RELAY
ACCI
P3
CCH
COM
BLU
RED
RED
BLK
Figure 21: Energizing the Modulating Valve
