CONFIGURATION
SWITCHES
RESET SWITCH
See the Troubleshooting section at the end of this document for more information about the function of this switch.
E2/P SWITCH (DHM) TERMINAL FUNCTION
The E2/P switch is located on the back of the thermostat body (see fig. 2). This switch controls how the DHM terminal will be energized.
1.In the P position (up) the DHM terminal will be energized on a call for dehumidification.
2.In the E2 position (down) the DHM terminal will always be energized except on a call for dehumidification. The switch must be in the E2 position on some electronically controlled variable speed blower systems.
1
S18
2
P S19
E2
1Reset switch
2E2/P switch
Figure 2. Switch locations on back of thermostat body
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 diagram below. A relay (customer provided) should be installed as shown in Fig. 5 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-
NOTE: If you have a two stage compressor, the thermostat software will lengthen cycle times for the first stage of cool. The longer cycles will improve dehumidification while cooling, allowing the DHM terminal not to be used on a two stage compressor system.
Selecting P - DHM Energizes on call for
P
Dehumidification
Selecting E2 - DHM Deenergizes on call for Dehumidification
E2
R | C | Y1 | G | DHM |
N.C.
N.O.
Customer supplied relay rated for blower motor load
Cool Fan Speed
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Control | Fan |
Module | Heat |
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24VAC
NEUTRAL
120 VAC
TRANSFORMER
Figure 3. Typical Wiring for Dehumidifier System
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| or equivalent | 24 VAC |
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| Humidifier | 120 VAC |
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Figure 4. Typical Wiring for 120V Humidifier System
HMR
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Humidifier |
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System | 24 VAC |
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Figure 5. Typical Wiring for 24V Humidifier System
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