Control apparatus for a two-speed heat pump
AssigneeCarrier Corporation
InventorMichael E. Smorol
Life of this patent
Estimating the term…
Abstract
Apparatus and a method for controlling the operation of a multiple speed heat pump air conditioning system. Circuitry is provided to regulate the heat pump compressor motor for multiple speed compressor operation in both the cooling and heating modes of operation. Additional electric resistance heaters are controlled by the circuitry to supply heating needs unsatisfied by heat pump operation.
Claims12
A control circuit for air conditioning apparatus for providing heating and cooling to an area to be conditioned including a refrigeration system having indoor and outdoor heat exchangers, a compressor powered by a multispeed motor, and expansion means connected to form a refrigerant flow control circuit which comprises:
- means for energizing the compressor motor at low speed,
- means for energizing the compressor motor at high speed,
- means for switching between the cooling mode of operation and the heating mode of operation,
- a first temperature sensitive means in communication with the air in the enclosure, said first temperature sensitive means being connected in both the cooling mode and the heating mode to the means for energizing the compressor motor at low speed upon the temperature of the enclosure varying a first predetermined amount and to the means for energizing the compressor motor at high speed upon the temperature in the enclosure varying a second predetermined amount;
- a second temperature sensitive means in communication with outdoor ambient air responsive only in the heating mode for energizing the means for actuating the compressor motor at high speed regardless of whether or not the temperature in the enclosure varied the second predetermined amount when the ambient air temperature is below a first predetermined level;
- and
- defrost means for operating the refrigeration system in the cooling mode when a defrost need is sensed.
A method of controlling air conditioning apparatus supplying conditioned air to an enclosure, including a refrigeration system capable of being operated to provide either heating or cooling having a compressor powered by a multi-speed motor, an indoor heat exchanger, an outdoor heat exchanger, and expansion means which comprises the steps of:
- sensing the temperature of the air in the enclosure;
- energizing the compressor motor to provide heating in the first speed of operation when the temperature of the enclosure air falls below a first level;
- energizing the compressor motor to provide heating at a second speed of operation when the temperature of the enclosure air falls below a second level;
- sensing the temperature level of the outdoor ambient air;
- and
- energizing the compressor motor to provide heating in a second speed of operation regardless of whether the indoor air has reached the second level when the outdoor air is below a first predetermined level.
A reversible vapor compression refrigeration system for supplying heating and cooling to an enclosure having an indoor heat exchanger, an outdoor heat exchanger, a reversing means, an expansion means and a compressor capable of multi-speed operation connected to a multi-speed motor which comprises:
- means for energizing the motor in a first speed of operation;
- means for energizing the motor at a second speed of operation;
- a first temperature sensitive device connected to actuating the means for energizing the motor at the first speed of operation when the temperature of the enclosure falls below the first level;
- a second temperature sensitive device connected to actuate the means for energizing the motor at a high speed of operation when the temperature of the enclosure falls below a second predetermined level;
- a third temperature sensitive device connected to actuate the means for energizing the motor at a low speed of operation if the temperature of the enclosure rises above a third predetermined level;
- a fourth temperature sensitive device connected to actuate means for energizing the motor at a high speed of operation if the temperature of the enclosure rises above a fourth predetermined level;
- means for energizing the reversing means when the unit is in the cooling mode of operation;
- and
- a fifth temperature sensitive device in communication with the outdoor ambient air for energizing the means for energizing the motor at a second speed of operation when the unit is in the heating mode of operation and the outdoor ambient air temperature falls below a fifth predetermined level.
Dependencies are inferred from the claim text.