Johnson Controls BQ 036, BQ 060 Electric Heat Limit Control Setting, Heat Anticipator Setpoints

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364985-XIM-B-0508

DEFROST MODE

As mentioned earlier, the defrost control (DC) utilizes a time/temperature defrost scheme. The following two conditions must be met before the DC will enter a defrost mode:

The defrost thermostat (SD) must be closed. This nor- mally open thermostat is mounted on the liquid line and is set to close at 28 ± 4°F.

Once the defrost thermostat closes, the defrost control starts a run timer that must be satisfied before defrost can begin. This is accumulated compressor run time. The selection pin is factory set at 60 minutes, but is field adjustable to 30, 60 or 90 minutes.

When the DC enters the defrost mode, it’s on-board defrost relay is powered. This energizes the reversing valve, de-energizes the condenser fan motor and ener- gizes the unit’s optional electric heater. The DC remains in defrost mode until either of the following two conditions is met:

1.The liquid line thermostat is open. It is set to open at 55 ± 4°F.

2.The maximum defrost run time of 10 minutes is met.

FORCED DEFROST

The processor on the defrost board is only energized when the defrost sensor (DS) is closed.

To create a forced defrost:

1.The DS must either be closed or a jumper must be placed across the DFS terminals on the board.

2.Place a jumper across the test pin terminals on the board.

Depending on the selected defrost minimum run time of 30, 60 or 90 minutes, the board will go into defrost in 7.5, 15 or 22.5 seconds.

The DC will remain in defrost until the jumpers across the DS and the test pin terminals are removed.

Once the jumpers are removed, the board then ter- minates defrost when the DS opens or a maximum of 10 minutes after the test pin jumper is removed, whichever comes first.

SAFETY CONTROLS

The control circuit includes the following safety con- trols:

1.Temperature Limit Switch (TLS) - This control is located inside the heater compartment and is set to open at the temperature indicated in the Electric Heat Limit Control Setting Table 30. It resets auto- matically. The limit switch operates when a high temperature condition, caused by inadequate sup- ply air flow occurs, thus shutting down the heater and energizing the blower.

TABLE 30: ELECTRIC HEAT LIMIT CONTROL SETTING

VOLTAGE

kW

TEMPERATURE LIMIT SWITCH

Open Temp ºF

 

 

 

 

 

5

1

140

 

7

1,3

140

 

 

 

 

 

10

1,2,3

140

230-1-60

15

2,4,6

140

 

 

 

 

 

20

1,2,3,4,5

140

 

6

150

 

 

 

 

 

 

 

30

1,2,3,4,5,6

150

 

5

1,2,3

140

 

7

1,2,3

140

 

10

1,2,3

150

230-3-60

15

2,4,6

140

 

 

 

 

 

20

1,2,3,4,5,6

150

 

30

1,3,5

160

 

 

 

 

2,4,6

150

 

 

 

 

 

 

 

7

2,4,6

140

 

 

 

 

 

10

2,4,6

140

460-3-60

15

2,4,6

140

 

 

 

 

 

20

3

160

 

30

3

150

 

10

2,4,6

140

575-3-60

15

2,4,6

140

 

 

 

20

5

160

 

 

30

5

150

HEAT ANTICIPATOR SETPOINTS

It is important that the anticipator setpoint be correct. Too high of a setting will result in longer heat cycles and a greater temperature swing in the conditioned space. Reducing the value below the correct setpoint will give shorter “ON” cycles and may result in the low- ering of the temperature within the conditioned space.

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Contents Installation Table of Contents List of Figures List of TablesInspection Safety ConsiderationsGeneral ReferenceProduct Nomenclature Ton Sunline Simplicity Model Number NomenclatureLimitations InstallationInstallation Safety Information Unit Application Data BQDuctwork Rigging and HandlingClearances Condensate DrainCompressors Service AccessFilters Typical Power Wiring OPTIONS/ACCESSORIES Power and Control WiringControl Wire Sizes ThermostatElectric Heater CFM Limitations Minimum Position Adjustment Enthalpy Setpoint Adjustment BQ 4 Point Loads Weight Distribution BQ 6 Point Loads Weight DistributionOperating Weights LBS Physical DataMCA Pwr Max Size Motors Fuse XIM-B-0508 Pwr Max MCA1 Electric Heat Correction Factors Voltage LIMITATIONS1Unit with Economizer Rainhood Unit Dimensions Rear View Minimum ClearancesRPM BHP BHP RPM BHP Belt Drive Blower Motor and Drive Data Belt Drive RPM SelectionStatic Resistances Drive Selection Factor Supply AIR Blowers PhasingChecking Supply AIR CFM Sequence of Operations Overview OperationCooling Sequence of Operation Cooling Operation Errors Compressor Protection Safety ControlsReset Flash CodesElectric Heat Limit Control Setting Heat Anticipator SetpointsTroubleshooting START-UP CoolingXIM-B-0508 Unit Flash Codes Unit Control Board Flash CodesMotors MaintenanceNormal Maintenance Outdoor CoilXIM-B-0508 Johnson Controls Unitary Products Johnson Controls Unitary Products York Drive Norman, OK

BQ 048, BQ 036, BQ 060 specifications

Johnson Controls has established itself as a leading player in the HVAC and building management industries, and its BQ series of chillers - including the BQ 060, BQ 036, and BQ 048 - reflects this commitment to innovation and efficiency. These models are designed to provide advanced cooling solutions suitable for a variety of commercial applications.

The BQ 060 is particularly notable for its high-performance capabilities. With a cooling capacity of 60 tons, it utilizes variable-speed compressors, allowing it to adjust its performance based on the cooling demand. This flexibility not only enhances energy efficiency but also reduces operational costs. The unit incorporates advanced microprocessor controls that facilitate seamless integration with building management systems, enabling real-time monitoring and adjustments.

Moving on to the BQ 036, this model is engineered for facilities that require a smaller footprint but still demand reliability and efficiency. With a cooling capacity of 36 tons, it features a compact design without compromising on performance. The BQ 036 also employs environmentally friendly refrigerants, aligning with Johnson Controls' commitment to sustainability. Enhanced insulation and sound-dampening technologies make it an ideal choice for noise-sensitive environments, ensuring comfort without sacrificing efficiency.

The BQ 048 lies in between the two, with a capacity of 48 tons, making it versatile for medium-sized commercial buildings. Its design incorporates a modular approach, allowing for easy scalability in future expansions. This model also features energy recovery options that can utilize excess heat to improve overall efficiency, further solidifying its role in sustainable building practices. Its user-friendly interface enhances operability, simplifying management for building operators.

All three models of the BQ series share key characteristics, such as robust construction to withstand diverse environmental conditions, and low maintenance requirements thanks to their durable components. They utilize advanced technologies for temperature control and energy efficiency, including an intelligent controller that automates more routine tasks. Together, the BQ 060, BQ 036, and BQ 048 offer comprehensive solutions that cater to the growing demands of energy efficiency, sustainability, and reliability in modern building operations. With these chillers, Johnson Controls continues to lead the way in shaping the future of HVAC solutions.
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