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US 11,768,022 B2Granted
Liquid transfer pump cycle
AssigneeLennox Industries Inc.
InventorsCarl T. Crawford, Robert B. Uselton
Life of this patent
Estimating the term…
Abstract
A method of initiating a low-energy cooling mode using a controller of an HVAC system includes measuring a temperature of ambient air proximal to a condenser coil and determining whether the temperature of the ambient air proximal the condenser coil is less than a temperature threshold. If the temperature of the ambient air is less than the temperature threshold, the HVAC system is configured to operate in a low-energy cooling mode. In the low-energy cooling mode, the controller opens a first bypass valve to allow a refrigerant to bypass a compressor and the compressor is powered off. The HVAC system is operated until a cooling demand has been met.
Claims20
An HVAC system configured to provide low-energy cooling, the HVAC system comprising:
- an evaporator coil comprising an evaporator coil inlet and an evaporator coil outlet;
- a condenser coil comprising a condenser coil inlet and a condenser coil outlet, the condenser coil outlet being coupled to the evaporator coil inlet, the condenser coil comprising:
- a primary cooling path coupled to a first collector, wherein the primary cooling path comprises a first cooling path having a first cooling-path inlet and a first cooling-path outlet;
- a secondary cooling path coupled to a secondary cooling path inlet;
- and
- the first cooling-path outlet is coupled to the secondary cooling path inlet via a first collection tube to direct a refrigerant to the secondary cooling path from the first collector of the primary cooling path, wherein the first collection tube bypasses a second primary cooling path inlet and a second primary cooling path outlet;
- a first bypass valve comprising a first bypass valve inlet coupled to the evaporator coil outlet and a first bypass valve outlet coupled to the condenser coil inlet;
- a second bypass valve disposed in parallel with a thermal expansion valve between a liquid pump and the evaporator coil inlet;
- and
- an HVAC controller configured to:
- measure, using a temperature sensor, a temperature of ambient air proximal to the condenser coil;
- determine whether the temperature of the ambient air proximal to the condenser coil is less than a temperature threshold specified by the HVAC system;
- and
- responsive to a determination that the temperature of the ambient air is not less than the temperature threshold specified by the HVAC system, configure the HVAC system to operate by closing the first bypass valve, powering on a compressor, and powering off the liquid pump.
11 more elements
An HVAC system configured to provide low-energy cooling, the HVAC system comprising:
- an evaporator coil comprising an evaporator coil inlet and an evaporator coil outlet;
- a condenser coil comprising a condenser coil inlet and a condenser coil outlet, the condenser coil outlet being coupled to the evaporator coil inlet, the condenser coil comprising:
- a primary cooling path coupled to a first collector, wherein the primary cooling path comprises a first cooling path having a first cooling-path inlet and a first cooling-path outlet;
- a secondary cooling path coupled to a secondary cooling path inlet;
- and
- the first cooling-path outlet is coupled to the secondary cooling path inlet via a first collection tube to direct a refrigerant to the secondary cooling path from the first collector of the primary cooling path, wherein the first collection tube bypasses a second primary cooling path inlet and a second primary cooling path outlet;
- a first bypass valve comprising a first bypass valve inlet coupled to the evaporator coil outlet and a first bypass valve outlet coupled to the condenser coil inlet;
- and
- an HVAC controller configured to:
- measure, using a temperature sensor, a temperature of ambient air proximal to the condenser coil;
- determine whether the temperature of the ambient air proximal the condenser coil is less than a temperature threshold specified by the HVAC system;
- responsive to a determination that the temperature of the ambient air is less than the temperature threshold specified by the HVAC system, configure the HVAC system to operate in a low-energy cooling mode.
9 more elements
An HVAC system configured to provide low-energy cooling, the HVAC system comprising:
- an evaporator coil comprising an evaporator coil inlet and an evaporator coil outlet;
- a condenser coil comprising a condenser coil inlet and a condenser coil outlet, the condenser coil outlet being coupled to the evaporator coil inlet, the condenser coil comprising:
- a primary cooling path coupled to a first collector;
- a secondary cooling path coupled to a secondary cooling path inlet;
- and
- a first cooling-path outlet coupled to the secondary cooling path inlet via a first collection tube to direct a refrigerant to the secondary cooling path from the first collector of the primary cooling path, wherein the first collection tube bypasses a second primary cooling path inlet and a second primary cooling path outlet;
- a first bypass valve comprising a first bypass valve inlet coupled to the evaporator coil outlet and a first bypass valve outlet coupled to the condenser coil inlet;
- and
- an HVAC controller configured to:
- measure, using a temperature sensor, a temperature of ambient air proximal to the condenser coil;
- determine whether the temperature of the ambient air proximal the condenser coil is less than a temperature threshold specified by the HVAC system;
- responsive to a determination that the temperature of the ambient air is less than the temperature threshold specified by the HVAC system, configure the HVAC system to operate in a low-energy cooling mode by opening a first bypass valve, powering off a compressor, powering on a liquid pump, closing a check valve, and opening a second bypass valve.
9 more elements
Dependencies are inferred from the claim text.