LENNOX 603364-29 Enthalpy Sensor Kit
INSTALLATION INSTRUCTIONS
FOR ENTHALPY SENSOR KIT (603364-29; 11G21) USED WITH HIGH PERFORMANCE ECONOMIZERS ON ZG/ZC/ZH 036, 048, 060, 072 & QG/QC/QZ, 036, 042, 048, 060 AND TAA/ELA/EL_XA UNITS
Shipping and Packing List
Package 1 of 1 contains:
- 1 – Temperature and humidity sensor
- 1- Wiring harness (used for differential sensing only)
- 1- Bag assembly containing:
- 2-#10-16 X 5/8” SDST screws
Check packaging for shipping damage. Contact the last carrier immediately if any shipping damage is found.
WARNING: Improper installation, adjustment, alteration, service or maintenance can cause property damage, personal injury or loss of life. Installation and service must be performed by a licensed professional HVAC installer or equivalent, service agency, or the gas supplier
Application
Sensors provide input to determine free cooling suitabil-ity. The enthalpy sensor provided in this kit senses both sensible temperature and humidity. See table 1 for usage.
Refer to economizer installation instructions.
Note – Differential sensor applications must use the same two sensors.
TABLE 1 | |
Sensors | Dampers modulate to maintain 55°F mixed air (R1) when: |
Single OA Enthalpy Not approved for CA Title 24 | OA temperature and humidity (A7) is lower than free cooling setpoint. |
Differential Enthalpy
– 1 in OA & 1 in RA Not approved for CA Title 24 |
OA temperature and humidity (A7) is lower than RA temperature and humidity (A62). |
CAUTION As with any mechanical equipment, contact with sharp sheet metal edges can result in personal injury. Take care while handling this equipment and wear gloves and protective clothing.
ZG/ZC/ZH – Single Enthalpy
Note – Install the return air sensor before installing option-al power exhaust dampers and gravity exhaust dampers. If gravity exhaust, power exhaust, or hoods are already installed, remove from unit.
- Disconnect all power to unit.
- Remove filter access panel and return air access panel. If hood is already installed, remove hood. See figure 1.
- Set the DIP switch on kit sensor to appropriate “OA“ setting as indicated on sensor.
- Replace existing RT26 OA sensor with new A7 sensor from this kit. See figure 2 for sensor location.
- On A6 economizer control, remove orange wires going to terminals marked “OAT” and reconnect them to free terminals marked “SBUS”. Discard harness provided in kit. See figure 4.
- Follow economizer installation instruction for setup.
ZG/ZC/ZH – Differential Enthalpy
Note – Install the return air sensor before installing option-al power exhaust dampers and gravity exhaust dampers. If gravity exhaust, power exhaust, or hoods are already installed, remove from unit.
- Disconnect all power to unit.
- Remove filter access and return air access panel. If hood is already installed, remove hood.
- Set the DIP switch on one kit sensor to “OA” setting and the second kit sensor to “RA” setting as indicated on the sensor.
- Replace existing RT26 OA sensor with new A7 kit sensor set to “OA”. See figure 2 for sensor location.
- On A6 economizer control, remove orange wires going to terminals marked “OAT” and reconnect them to free terminals marked “SBUS”. See figure 4.
- Install new sensor from second kit as A62 RA sensorin the return air with screws provided. Be sure not to obstruct the damper movement and not to damage wires.
- Connect harness from EITHER kit between the A62 RA sensor and free “S-BUS” terminals on the A6 economizer control. Be sure to route wires away form moving parts. Discard second harness.
- Follow economizer installation instruction for setup
QG/QC/QH – Single Enthalpy
Note – Differential Enthalpy not available on Q-series units.
Note – Install the return air sensor before installing option-al power exhaust damper and gravity exhaust damper. If Gravity exhaust, power exhaust or hoods are already in-stalled, remove from unit.
- Disconnect all power to unit.
- Remove blower access panel. If hood is already installed, remove hood.
- Set the DIP switch on kit sensor to appropriate “OA” setting as indicated on the sensor.
- Replace the outdoor air sensor with the sensor provided in this kit. See figure 3 for sensor install location.
- On the economizer controller, remove wires going to terminals marked “OAT” and reconnect them to free terminals marked “SBUS”. Discard harness provided in kit. See figure 4.
- Follow economizer installation instructions for setup.
TAA/ELA/EL_XA – Single Enthalpy
- Disconnect all power to unit.
- Set the DIP switch on kit sensor to appropriate “OA“ setting as indicated on sensor.
- Replace existing RT26 OA sensor, if applicable, and replace with new A7 sensor from this kit. See figure 5 for sensor location.
- Remove economizer control access panel. See figure 5.
- On A6 economizer control, remove orange wires going to terminals marked “OAT” and reconnect them to free terminals marked “SBUS”. Discard harness provided in kit. See figure 4.
- Follow economizer installation instruction for setup
TAA/ELA/EL_XA – Differential Enthalpy
- Disconnect all power to unit.
- Set the DIP switch on one kit sensor to “OA” setting and the second kit sensor to “RA” setting as indicated on the sensor.
- Replace existing RT26 OA sensor with new A7 kit sensor set to “OA”. See figure 5 for sensor location.
- Remove economizer control access panel. See figure 5.
- On A6 economizer control, remove orange wires going to terminals marked “OAT” and reconnect them to free terminals marked “SBUS”. See figure 4.
- Install new sensor from second kit as A62 RA sensor in the return air with screws provided. Be sure not to obstruct the damper movement and not to damage wires.
- Connect harness from EITHER kit between the A62 RA sensor and free “S-BUS” terminals on the A6 economizer control. Be sure to route wires away form moving parts. Discard second harness.
- Follow economizer installation instruction for setup.
Documents / Resources
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LENNOX 603364-29 Enthalpy Sensor Kit [pdf] Instruction Manual 603364-29, Enthalpy Sensor Kit, 603364-29 Enthalpy Sensor Kit, Sensor Kit |