Time Delays

The unit time delays include:

SFive minute time delay to start cooling or heating operation when there is a call from the thermostat or user interface. To bypass this feature, momentarily short and release Forced Defrost pins.

SFive minute compressor re-cycle delay on return from a brown-out condition.

STwo minute time delay to return to standby operation from last valid communication (with Evolution only).

SOne minute time delay of outdoor fan at termination of cooling mode when outdoor ambient is greater than or equal to 100_F.

SFifteen second delay at termination of defrost before the auxiliary heat (W1) is de-energized.

STwenty second delay at termination of defrost before the outdoor fan is energized.

SThirty second compressor delay when quiet shift enabled.

SOn 226A, 266A, 286A models there is a 1 minute time delay between staging from low to high and from high to low capacity. On 288A models there is no delay; the compressor will change from low to high and from high to low capacity “on the fly” to meet the demand.

Pressure Switches

The Puronr two-stage air conditioner contains two pressure switches to prevent system operation if the pressures get excessively high or low. The air conditioner low pressure switch in the suction line opens at 50 PSI and closes at 95 PSI. The high pressure switch opens at 670 PSI and closes at 470 PSI. Both pressure switch settings are considerably higher than on comparably sized R-22 units. The high and low pressure switches can be identified by their pink stripe on the switch’s electrical wires.

The Puronr two-stage heat pump contains a loss of charge switch in the suction line on 286BNA and 288ANA, and liquid line on 226A and 266A which opens at 23 PSI and closes at 55 PSI. See troubleshooting section for sequence when a pressure switch trip occurs.

Muffler, Accumulator, Reversing Valve (RVS)

The Puronr two-stage air conditioners and heat pumps have a compressor discharge line muffler, to dampen sound pressure pulsations.

The Puronr two-stage heat pumps have a specifically designed reversing valve, for Puronr application and an accumulator for storing excess liquid refrigerant during the heating mode to prevent damaging flood-back.

Thermistors

Outdoor Ambient Thermistor

The Puronr two-speed air conditioner and heat pump units have an outdoor ambient air thermistor. The control board must know the outdoor air temperature so it can activate various functions. These functions include:

SActivating the compressor crankcase heater when ever the outdoor unit is in the off cycle.

SThe fan motor speed changes for both air conditioner and heat pump on the ECM equipped units.

Outdoor Coil Thermistor(OCT)

The coil or defrost thermistor is the same thermistor used to monitor outdoor air temperature. The control board must know the coil temperature so it can activate various functions. These functions include:

SFrost sensing on heat pumps

SCoil-vs-Ambient temperature relationship

SLow ambient cooling operation

Thermistor Curve

The resistance vs. temperature chart enables the service technicians to check thermistor resistance, regardless of the temperature.

For example, at a 60_F temperature, thermistor resistance should be around 16,000 Ohms. (See Fig. 34.)

We will talk about the thermistor in more detail when we review the control board fault codes.

THERMISTOR CURVE

 

90

(KOHMS)

80

70

 

 

60

RESISTANCE

50

20

 

40

 

30

 

10

 

0

0

20

40

60

80

100

120

(-17.77)

(-6.67)

(4.44)

(15.56)

(26.67)

(37.78)

(48.89)

 

 

TEMPERATURE °F (°C)

 

 

A08054

Fig. 34 – Resistance Values Versus Temperature

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Image 49
Bryant R-22 service manual Time Delays, Muffler, Accumulator, Reversing Valve RVS, Thermistors

R-22 specifications

The Bryant R-22 stands out in the landscape of residential heating and cooling systems with its combination of efficiency, durability, and modern technology. Designed primarily for homeowners seeking comfortable climate control solutions, the R-22 model delivers consistent performance throughout varying seasonal extremes.

One of the main features of the Bryant R-22 is its high energy efficiency. Rated with a SEER (Seasonal Energy Efficiency Ratio) that meets or exceeds industry standards, this air conditioning unit is designed to reduce energy consumption while providing optimal cooling. This not only helps in lowering monthly utility bills but also promotes environmentally responsible usage.

Another notable characteristic is the unit's durability. Constructed with a robust cabinet and high-quality components, the R-22 is built to withstand the rigors of daily use, with protective features that enhance its longevity. The cabinet comes with a powder-coated finish that resists corrosion and harsh weather conditions, ensuring that the unit stays functional and aesthetically pleasing for years.

The Bryant R-22 also incorporates advanced technology to improve user experience. One such innovation is the SmartSet technology, which allows homeowners to program their unit to optimize comfort levels according to their specific needs. This programmable capability enhances energy savings and ensures that the home remains at the desired temperature when residents are present.

Moreover, the unit features a Quiet Operating System that significantly reduces noise levels, making it suitable for residential areas where noise might be a concern. The design minimizes vibrations and optimizes airflow, creating a comfortable environment without disruptive sounds.

For added convenience, the Bryant R-22 is compatible with various thermostat options, including Wi-Fi-enabled models. This allows users to control their home's climate from anywhere using a smartphone app, facilitating effortless adjustments and monitoring of energy usage.

Finally, the Bryant R-22 is backed by a solid warranty, providing peace of mind for homeowners. This commitment to quality and customer satisfaction is a testament to Bryant’s dedication to producing reliable and efficient HVAC solutions. Overall, the Bryant R-22 is an exemplary choice for those looking to enhance their home comfort with the latest in HVAC technology.