White Rodgers 1F95-1291 specifications Humidity and Sensors

WIRING DIAGRAMS

Figure 4 – Humidity and Sensors

HM	DHM
Humidification Terminal,	De-energizes on call for
Energizes on call for	Dehumidification to
heat if Humidity setpoint	lower the fan speed.
is above room humidity.	The DHM terminal is
Can also be used to	only used on systems
provide humidification	with a compatible
independent of a call for	dehumidification feature
heat and/or in cooling	that have the required
mode if Automatic	terminal connection on
Humidification is	the contol module or
selected in Configura-	have a relay installed to
tion Menu item #34	lower the fan speed

+	S	-
Supply voltage	Remote	Supply voltage
to remote	temperature	to remote
temperature	sensor signal	temperature
sensor		sensor

Dehumidification wiring without an electronically controlled variable speed blower system for single stage compressor system only.

If you have a single stage compressor system see the dia- gram below. A relay (customer provided) should be installed as shown in Fig 7 to switch the fan speed to the next lower speed on a call for dehumidification from the thermostat. The reduction in air flow allows the coil to remove more humidity from the air. The relay should be rated for blower motor load. Since this configuration reduces the air flow in cooling, the

anti-freeze-up control (White-Rodgers CAFC) or equivalent is recommended. The CAFC prevents the air conditioning coil from freezing due to low air flow, dirty filters, low refrigerant pressure, etc. The CAFC snaps onto the suction line close to the evaporator coil as possible and breaks the compressor circuit when the suction line drops below 38°F and re-make the circuit at 46°F.

Figure 5 – Typical Wiring for Dehumidifier System

		Normal High
DHM
	No	Med
Relay
		1
90-293Q	2	Low
or equivalent	NC	Dehum
		Speed Fan
N		“Heat Fan Output”
“Cool Fan Output”

1Normal Cool speed position (DHM energized)

2 Dehum speed mode (DHM de-energized) N

Figure 6 – Typical Wiring for 120V Humidifier System

HM			R
Relay			HOT
90-290Q
or equivalent		24 VAC		120 VAC
			NEUTRAL
Humidifier	HOT		TRANSFORMER
	NEUTRAL	120 VAC
System
Figure 7 – Typical Wiring for 24V Humidifier System

HM

Humidifier

System

	R
24 VAC		HOT	120 VAC
		NEUTRAL
	TRANSFORMER		4