035-18265-001-A-0202

SEQUENCE OF OPERATION

HEATING

When the thermostat calls for “HEAT”, the thermostat terminal “W” is energized, energizing the combustion air blower.

After airflow is established, the air proving switch closes, the hot surface ignitor is energized and the pilot valve opens ignit- ing the pilot flame. The system will try to light the pilot for 90 seconds. After 90 seconds, the pilot valve will close and the system will retry in 5 minutes.

The flame rod senses a flame and de-energizes the ignitor opening the main gas valve and the main burners light.

30 seconds after the main burners light the circulating fan is en- ergized at the heating speed.

When the thermostat is satisfied, terminal “W” is de-energized, de-energizing the ignition system closing the gas valve.

After a 5 second postpurge timing period, the combustion air blower is de-energized and the heat fan off timing begins.

When this field selected heat fan off timing is completed the cir- culating fan is de-energized.

If the primary, rollout or auxiliary limit switches open, the ther- mostat and ignition system is de-energized and the gas valve closes. The combustion blower and the circulating fan, at heat speed, are energized.

The combustion blower remains energized for the 5 second postpurge timing period if the primary, rollout or auxiliary limit switches remake the contact (the rollout and auxiliary limit

switches must be manually reset). The circulating fan remains energized for the selected heat delay off timing.

Normal operation of the system resumes.

COOLING

When the thermostat calls for “COOL”, the thermostat termi- nals “G” and “Y” are energized signaling the compressor and outdoor fan to run.

After a cool fan on delay timing of 2 seconds, the circulating fan is energized at cooling speed.

When the thermostat is satisfied, terminals “G” and “Y” are de- energized, de-energizing the compressor and outdoor fan.

After a cool fan off delay timing of 30 seconds the circulating fan is de-energized.

CIRCULATING FAN

When the thermostat calls for “FAN”, the thermostat terminal “G” is energized signaling the circulating fan to run at the heat speed 2 seconds after the “G” terminal is energized.

If a call for “HEAT” occurs, the circulating fan continues to run at the heat speed.

If a call for “COOL” occurs, the circulating fan switches to cool speed after a 4 second delay.

When the thermostat ends the call for “FAN”, the thermostat terminal “G” is de-energized, de-energizing the circulating fan.

START-UP

PRE-START CHECK LIST

Complete the following checks before starting the unit.

1.Check the type of gas being supplied. Be sure that it is the same as listed on the unit nameplate.

2.Make sure that the vent outlet air hoods has been properly installed.

8.Turn the gas valve switch to the “ON” position.

9.Replace the control access panel.

10.Turn on all electric power to the unit.

11.Set the thermostat to the desired setting.

12.If the unit will not operate, follow the instructions “To Turn Off Gas To Appliance” and call your service technician or gas supplier.

OPERATING INSTRUCTIONS

1.STOP! Read the information on the unit safety label.

2.Set the thermostat to the “OFF” position.

3.Turn off all electrical power to the unit.

4.DO NOT try to light the burners by hand. This appliance is equipped with an ignition device which automatically lights the burners.

5.Remove the access panel.

6.Turn the gas valve switch to the “OFF” position.

7.Wait five (5) minutes to clear out any gas. If you then smell gas, STOP! Follow “B” in the information on the unit safety label. If you don't smell gas, go to the next step.

TO TURN OFF GAS TO UNIT

1.Set the thermostat to the “OFF” position.

2.Turn off all electric power to the appliance if service is to be performed.

3.Remove the control access panel.

4.Turn the gas valve switch to the “OFF” positionDO. NOT

FORCE.

5.Replace the control access panel.

POST-START CHECK LIST (GAS)

After the entire control circuit has been energized and the heat- ing section is operating, make the following checks:

1.Check for gas leaks in the unit piping as well as the supply piping.

Unitary Products Group

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York D1NA018, D2NA060 installation instructions Sequence of Operation, Start-Up
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D1NA018, D2NA060 specifications

The York D1NA018 and D2NA060 are advanced rooftop air conditioning units that combine efficiency, reliability, and innovative technologies to provide optimal climate control for commercial buildings. These units are designed to deliver robust performance while ensuring ease of installation and maintenance.

The D1NA018 is a compact model with a nominal cooling capacity of 1.5 tons, making it an ideal choice for smaller commercial spaces or applications where space is limited. In contrast, the D2NA060 offers a higher cooling capacity of 5 tons, catering to larger areas or environments that require more substantial cooling solutions. Both units are built with high-quality materials that enhance their durability and extend their operational life.

One of the key features of both models is their energy efficiency. They utilize advanced scroll compressor technology that ensures a quieter operation while optimizing energy consumption. The units are designed to achieve high Seasonal Energy Efficiency Ratios (SEER), which makes them compliant with modern energy regulations. This not only reduces operational costs but also minimizes the environmental impact.

Additionally, the York D1NA018 and D2NA060 come equipped with enhanced airflow technologies. They feature multi-speed blowers that can adapt to varying load conditions, ensuring consistent temperature control throughout the indoor space. The airflow systems are designed to provide even distribution, enhancing comfort for occupants.

These units are also equipped with user-friendly control options. The integrated digital controls allow for precise temperature management and programming, further increasing efficiency. Building managers can easily monitor and control the units, leading to improved operational convenience.

Another standout characteristic is their ease of installation. The compact design and lightweight construction of the D1NA018 simplify rooftop installations. The D2NA060, while larger, maintains a straightforward installation process, ensuring minimal disruption to building operations.

In terms of maintenance, the York D1NA018 and D2NA060 incorporate features that facilitate routine service and upkeep. Access panels are strategically placed, allowing technicians to reach components quickly and perform necessary maintenance checks with ease.

Overall, the York D1NA018 and D2NA060 represent a blend of efficiency, innovation, and practicality, making them suitable choices for a wide range of commercial applications. Their advanced technologies provide reliable climate control while reducing energy consumption, making them a preferred option for businesses seeking sustainable solutions.
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