835961-UIM-D-0213
8Johnson Controls Unitary Products
DEHUMIDIFICATION CONTROL

A dehumidification control accessory 2HU06700124 may be used with

variable speed air handlers or furnaces in high humidity areas. This

control works with the variable speed indoor unit to provide cooling at a

reduced air flow, lowering evaporator temperature and increasing latent

capacity. The humidistat in this control opens the humidistat contacts on

humidity rise. To install, refer to instructions packaged with the acces-

sory. Prior to the installation of the dehumidification control, the jumper

across the HUMIDISTAT terminals on the indoor variable speed air han-

dler or furnace CFM selection board must be removed.

During cooling, if the relative humidity in the space is higher than the

desired set point of the dehumidification control, the variable speed

blower motor will operate at lower speed until the dehumidification con-

trol is satisfied. A 40-60% relative humidity level is recommended to

achieve optimum comfort.

If a dehumidification control is installed, it is recommended that a mini-

mum air flow of 325 cfm/ton be supplied at all times.

For connection diagrams for all UPG equipment refer to “Low Voltage

System Wiring” document available online at www.upgnet.com in the

Product Catalog Section.

CFM SELECTION BOARD SETTINGS

For proper system operation the CFM Selection control jumpers must

be set properly.

Refer to the Tabular Data Sheet for the recommended air flow settings

for each size condensing unit.

Set the cooling speed per the instructions for the air handler or furnace

by selecting the correct COOL and ADJ taps. Verify the airflow using

the LED display on the CFM selection board.

FIGURE 8: Typical Field Wiring (Air Handler / Electrical Heat) - (Three Phase)

FIGURE 9: Typical Field Wiring (Air Handler / Electrical Heat) (Single-Phase)

THERMOSTAT INDOOR UNIT
OUTDOOR UNIT
LOW VOLTAGETERMINALBLOCK
INAIR HANDLER WITH ELECTRIC HEAT
3,4
DEFROST
CONTROL
1FIELD
INSTALLED
JUMPER
GND.
SCREW
CONTACTOR
T2 T1
L2 L1
M
R
Y
O
W
G
T2
E2
RR
YY
O
O
W2 W
C
X
G
W1
GND.
LUG
POWER WIRING
24V CONTROLWIRING
(NEC CLASS 2)
JUMPERTERMINALS E AND W TO HEAT
ON FIRSTSTAGE DURING EMERGENCY HEAT.
1
2
TERMINALNOT USED ON ALL THERMOSTATS.
POWER WIRING
208/230-3-60
460-3-60
3CHECKTHE LOW VOLTAGETERMINAL BLOCK ON THE INDOOR UNIT FOR THE ACTUAL ARRANGEMENT OFTHE TERMINALS.
4CONNECTPOWER WIRING TO TERMINAL BLOCK 3TB ON UNITS WITHOUT ELECTRIC HEATOR CIRCUIT BREAKER.
ALLFIELD WIRING TO BE IN ACCORDANCE WITH ELECTRIC CODE (NEC) AND/OR LOCALCODES
RED
BLK
YEL
ORG
BRN
PUR
WHT
POWER
SUPPLY
208/230-3-60
460-3-60
T3
L3
W1/66
B or C
Lor X
B or C

THERMOSTAT INDOOR UNIT

OUTDOOR UNIT

LOW VOLTAGETERMINALBLOCK
INAIR HANDLER WITH ELECTRIC HEAT
DEFROST
CONTROL
FIELD
INSTALLED
JUMPER
DEHUMIDIFICATION CONTROLCONNECTION
(Humidistat* Jumper must be removed)
GND.
SCREW
CONTACTOR
T2 T1
L2 L1
M
R
Lor X
Y
O
W
G
T2
E2
RR
YY
O
O
W2 W
CC
X/L
G
W1
BK
GND.
LUG
CIRCUIT
BREAKER***
POWER WIRING
24V CONTROLWIRING
(NEC CLASS 2)
JUMPERTERMINALS E AND W TO HEAT
ON FIRSTSTAGE DURING EMERGENCY HEAT.
TERMINALNOT USED ON ALLTHERMOSTATS. POWER WIRING
208/230-1-60
230-1-50
CHECKTHE LOW VOLTAGETERMINAL BLOCK ON THE INDOOR UNIT FOR THE ACTUALARRANGEMENT OF THE TERMINALS.
CONNECTPOWER WIRING TO TERMINAL BLOCK 3TB ON UNITS WITHOUT ELECTRIC HEATOR CIRCUIT BREAKER.
B or C

ALLFIELD WIRING TO BE IN ACCORDANCE WITH ELECTRIC CODE (NEC) AND/OR LOCALCODES

RED
BLK
YEL
ORG
WHT
PUR
BRN
1
2
3
4
1
3,4
W1/66