356214-XIM-A-0108

OPERATION

SEQUENCE OF OPERATIONS OVERVIEW

For these units, the thermostat makes a circuit between "R" and "Y1" for the first stage of cooling.

The call is passed to the unit control board (UCB), which then determines whether the requested opera- tion is available and, if so, which components to ener- gize.

For gas heating, the UCB monitors the "W1" call but does not handle the operation of the gas furnace. An ignition control board controls the gas heater operation.

For electric heat units, the UCB passes the call to the electric heater.

In both cases, when the "W1" call is sensed, the indoor air blower is energized following a specified heating delay.

If at any time a call for both heating and cooling are present, the heating operation will be performed. If operating, the cooling system is halted as with a com- pletion of a call for cooling. Heating always takes prior- ity.

COOLING SEQUENCE OF OPERATION

CONTINUOUS BLOWER

By setting the room thermostat fan switch to "ON," the supply air blower will operate continuously.

INTERMITTENT BLOWER

With the room thermostat fan switch set to "AUTO" and the system switch set to either the "AUTO" or "HEAT" settings, the blower is energized whenever a cooling or heating operation is requested. The blower is ener- gized after any specified delay associated with the operation.

When energized, the indoor blower has a minimum run time of 30 seconds. Additionally, the indoor blower has a delay of 10 seconds between operations.

NO OUTDOOR AIR OPTIONS

When the thermostat calls for the first stage of cooling, the low-voltage control circuit from "R" to "Y1" and "G" is completed. For first stage cooling, compressor #1,

condenser fan motor #1, and condenser fan motor #2 for 15 and 20T only (if the ambient temperature is above 60°F), are energized. After completing the spec- ified fan on delay for cooling, the UCB will energize the blower motor.

When the thermostat calls for the second stage of cool- ing, the low-voltage control circuit from "R" to "Y2" is completed. Compressor #2, and condenser fan motor #2, 25T only (if the ambient temperature is above 60°F), is energized, provided it has not been locked- out.

If there is an initial call for both stages of cooling, the UCB will delay energizing compressor #2 by 30 sec- onds in order to avoid a power in rush.

Once the thermostat has been satisfied, it will de-ener- gize Y1 and Y2. If the compressors have satisfied their minimum run times, the compressors and condenser fans are de-energized. Otherwise, the unit operates each cooling system until the minimum run times for the compressors have been completed. Upon the final compressor de-energizing, the blower is stopped fol- lowing the elapse of the fan off delay for cooling.

To be available, a compressor must not be locked-out due to a high or low-pressure switch or freezestat trip and the anti-short cycle delay (ASCD) must have elapsed.

ECONOMIZER WITH SINGLE ENTHALPY SENSOR -

When the room thermostat calls for "first-stage" cool- ing, the low voltage control circuit from "R" to "G" and "Y1" is completed. The UCB energizes the blower motor (if the fan switch on the room thermostat is set in the "AUTO" position) and drives the economizer damp- ers from fully closed to their minimum position. If the enthalpy of the outdoor air is below the setpoint of the enthalpy controller (previously determined), "Y1" ener- gizes the economizer. The dampers will modulate to maintain a constant supply air temperature as moni- tored by the discharge air sensor. If the outdoor air enthalpy is above the setpoint, "Y1" energizes com- pressor #1, condenser fan motor #1, and condenser fan motor #2, 15 and 20T only (if the ambient tempera- ture is above 60°F).

When the thermostat calls for "second-stage" cooling, the low voltage control circuit from "R" to "Y2" is completed. The UCB energizes the first available compressor If the enthalpy of the outdoor air is below the setpoint of the enthalpy controller (i.e. first stage

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Johnson Controls Unitary Products

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Sunlife Enterprises DM300, DM240, DM180 Sequence of Operations Overview, Cooling Sequence of Operation
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DM300, DM240, DM180 specifications

Sunlife Enterprises has made significant strides in the competitive market of digital management tools with their innovative lineup of products: the DM240, DM300, and DM180. Each of these devices has been engineered to cater to specific operational needs while sharing a common foundation of advanced technology, versatility, and user-centric design.

The DM240 is an entry-level model that caters to small businesses looking for an efficient digital management solution without the hefty price tag. With a compact design and intuitive user interface, the DM240 allows for seamless integration into various work environments. Key features include a high-resolution touchscreen display, which facilitates easy navigation and quick access to essential functions. The device supports wireless connectivity options, ensuring users can manage tasks from anywhere within their operating environment. The energy-efficient design of the DM240 also promotes sustainability without compromising performance.

Moving up the line, the DM300 offers enhanced capabilities for medium-sized enterprises. This model is powered by advanced processing technology, allowing for faster data handling and superior multitasking. The DM300 features expanded memory and storage options, ensuring that users can manage larger datasets effortlessly. Additionally, with built-in advanced security features like biometric authentication and encrypted data storage, businesses can ensure that sensitive information remains protected. The intuitive software interface of the DM300 is designed for ease of use while providing advanced analytics tools to enable users to make data-driven decisions.

At the top of the range is the DM180, a sophisticated solution tailored to large organizations with complex digital management needs. The DM180 showcases a state-of-the-art design with high-performance computing capabilities. It features an expansive multi-touch display, allowing multiple users to interact simultaneously, facilitating collaboration and teamwork. The DM180 is equipped with cloud integration options, promoting real-time data access and sharing among teams, regardless of location. Its scalability ensures that businesses can adapt the system to accommodate growth without compromising functionality. Moreover, it offers comprehensive reporting and analytics tools, empowering organizations to gain valuable insights into their operations.

In summary, Sunlife Enterprises’ DM240, DM300, and DM180 models stand out for their unique features designed to meet the evolving needs of businesses. With a focus on user experience, performance, and security, these devices are poised to help organizations enhance productivity and drive innovation in the digital management landscape.
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