Relative Humidity sensor wire terminal location
A unit with dehumidification installed will operate normally if a humidity sensor or humidistat is not
installed. The compressor will switch to the dehumidification mode for a total of three minutes
after 90 minutes of compressor run time in the cooling mode. Verification of the RH setpoint can be determined by measuring the dc voltage at TB1 and TB2 on the RTOM.
Verification of humidity setpoint
Calculation to convert mA to RH = (mA reading - 4) * 6.25
4mA = 0%
20mA = 100%
Example: (12mA - 4) * 6.25 = 50% RH
To measure the mA input current from the humidity sensor, disconnect the sensor wire that is connected to terminal 18 of LTB. Connect amp meter in series with the wire and terminal 18 of the LTB.
Humidity sensor measurements
Dehumidification/reheat is disabled if any of these conditions exist:
• Humidistat active OPEN from humidity stat• Active humidity < Active humidity set point –5%
• Outdoor air temperature < 40º F or Invalid or > 100ºF and 1 compressor
• Compressor 1 (or 2 for multi-compressor units) Auto or manual reset lockout
• Active call for heating
• Slave mode is active and requesting the supply fan off.
• Dehumidification setpoint is set to 0% (Tracer® Override)
• If using a zone sensor and unit mode is set to manual/heat and active zone temp > or equal to active zone cool setpoint
• If using a zone sensor and unit mode is set to manual/cool and active zone temp < active zone
heat setpoint + 0.5º F.
• Active unit mode = Off with zone sensor
WARNING:
Information in this article is intended for use by individuals possessing adequate backgrounds of electrical and mechanical experience and who comply with all federal, state, and local laws, rules, orders, or regulations related to the installation, service, or repair of a heating or central air conditioning product. Any attempt to install, service, or repair a heating or central air conditioning product may result in personal injury and/or property damage. The manufacturer or seller cannot be responsible for the interpretation of the information contained herein, nor can it assume any liability in connection with its use.