User's Manual

1068152-YTG-L-0815
178 Johnson Controls Unitary Products
5. Shall have an LED display independently showing the status of serial communication, running, errors, power,
all digital outputs, and all analog inputs.
6. Shall accept the following inputs: space temperature, setpoint adjustment, outdoor air temperature, indoor air
quality, outdoor air quality, compressor lock- out, fire shutdown, enthalpy switch, and fan status/filter status/
humidity/ remote occupancy.
7. Software upgrades will be accomplished by either local or remote download. No software upgrades through
chip replacements are allowed.
23 09 33 Electric and Electronic Control System for HVAC
23 09 33.13 Decentralized, Rooftop Units:
23 09 33.13.A. General:
1. Shall be complete with self- contained low- voltage control circuit protected by a resettable circuit breaker on
the 24- v transformer side. Transformer shall have 75VA capability.
2. Shall utilize color- coded wiring.
3. Shall include a central control terminal board to conveniently and safely provide connection points for vital
control functions such as: smoke detectors, phase monitor, gas controller, economizer, thermostat, DDC
control options, and low and high pressure switches.
4. The heat exchanger shall be controlled by an integrated gas controller (IGC) microprocessor. See heat
exchanger section of this specification.
23 09 33.23.B. Safeties:
1. Compressor over- temperature, over- current. High internal pressure differential.
2. Low- pressure switch.
a. Units with 2 compressors shall have different sized connectors for the circuit 1 and circuit 2 low and high
pressure switches. They shall physically prevent the cross- wiring of the safety switches between circuits
1 and 2.
b. Low pressure switch shall use different color wire than the high pressure switch. The purpose is to assist
the installer and service technician to correctly wire and or troubleshoot the rooftop unit.
3. High- pressure switch.
a. Units with 2 compressors shall have different sized connectors for the circuit 1 and circuit 2 low and high
pressure switches. They shall physically prevent the cross- wiring of the safety switches between circuits
1 and 2.
b. High pressure switch shall use different color wire than the low pressure switch. The purpose is to assist
the installer and service technician to correctly wire and or troubleshoot the rooftop unit.
4. Automatic reset, motor thermal overload protector.
5. Heating section shall be provided with the following minimum protections:
a. High- temperature limit switches.
b. Induced draft motor speed sensor.
c. Flame roll-out switch.
d. Flame proving controls
23 09 93 Sequence of Operations for HVAC Controls
23 09 93.13 Decentralized, Rooftop Units:
23 09 93.13 INSERT SEQUENCE OF OPERATION
23 40 13 Panel Air Filters
23 40 13.13 Decentralized, Rooftop Units:
23 40 13.13.A. Standard filter section