820results about How to "Avoid frost" patented technology

Airflow rates within a ventilation system are controlled using motor speed or torque and motor electric current or pressure. Fan speed or torque may be varied to compensate for differing restriction in ductwork, and may provide a constant airflow rate over a range of varying airflow restriction. Air handlers or air conditioning units may be mass produced in common configurations, and installed in different buildings or structures with different ductwork configurations. Methods operate a fan motor at a present speed or torque, sample speed or torque, sample current of the fan motor or pressure within the ventilation system, calculate a present airflow rate within the ventilation system, calculate a new input setting using the present airflow rate and a target airflow rate, change the speed or torque to the new input setting, and repeat these steps to converge on the target airflow rate, often avoiding overshoot.

A heat pump system is operable in winter mode and/or summer mode, and may be selectively operated in a defrost mode or cycle. The system includes an energy recovery module that receives and conditions air in a regeneration air channel. A pre-processing module is positioned downstream of the energy recovery module. The pre-processing module receives and heats air from the energy recovery module. A regeneration air heat exchanger is positioned downstream of the pre-processing module. The regeneration air heat exchanger receives and conditions air from the pre-processing module. The pre-processing module heats the air from the energy recovery module to increase efficiency of the regeneration air heat exchanger. During the defrost mode, a loop of regeneration air may be recirculated between the supply air channel and the regeneration air channel in order to defrost the regeneration air heat exchanger.

Air conditioning systems that cool and dehumidify spaces within enclosures, buildings having such systems, and methods of controlling humidity within a space. Embodiments adjust speed of a blower or fan motor based on inputs from sensors within the system, using automated processes, to reduce airflow rates to provide for lower temperatures of the cooling coil and to increase the ratio of latent to sensible heat transfer. Fan speeds may be increased as appropriate to avoid frost formation on the cooling coil, to give priority to cooling when temperatures within the space are high, or periodically to provide for mixing within the space.

The invention discloses an air-cooled heat pump air conditioner which comprises a compressor, an outdoor coil, a heat exchanger, a main liquid line and supercooling devices, wherein the supercooling devices comprise two or three of a supercooling coil, an economizer and a liquid-vapor separator with a supercooling function, the supercooling devices are arranged on the main liquid line, and liquid state refrigerants which circulate in the main liquid line can achieve repeatedly the supercooling through the supercooling devices. According to the air-cooled heat pump air conditioner, the performance of cooling/heating circulation of the air-cooled heat pump air conditioner is effectively improved, so that the air-cooled heat pump air conditioner is stable and reliable in operation and energy saving in a low-temperature environment.

A method for controlling a heat pump system is provided with air conditioning means connected to a controller and including a plurality of valves and expansion valves connected to each other through a refrigerant line and a bypass line, a compressor, an accumulator, an evaporator, an exterior condenser, an interior condenser, and an HVAC module having a PTC heater and a door at a warming mode, a cooling mode, a dehumidification mode, a dehumidification/defrosting mode, or an extremely low temperature dehumidification/defrosting mode according to selection of a driver.

A vertically operating door includes a flexible panel comprising two pliable sheets of material with a layer of thermal insulation between the two. The door includes means for preventing or relieving undesirable air pressure conditions inside the panel. In some cases, a hose from a suction inlet of a blower extends into the space between the two sheets so that when the door is closed with the bottom of the panel resting upon the floor, the blower draws out excess air that happens to leak into the hollow interior of the panel. In other cases, air passageways are created to release or redistribute the excess air inside the panel. The door includes an inflatable seal that helps prevent frost from forming on the door panel's vertical guide tracks, thus the door is particularly suited for refrigerated cold storage rooms.

The present invention provides a configuration of a vehicle heat exchanger. The configuration of the vehicle heat exchanger comprises an outdoor heat exchanger of a heat pump system of a vehicle air conditioning device and a low water temperature radiator used for cooling the low temperature heating elements, including a vehicle driving motor, and is characterized in that relative to the outdoor heat exchanger, the low water temperature radiator is arranged at the upstream side of a cooling airflow direction.

The invention discloses an efficient and compact pre-cooling heat exchanger for a pre-cooling gas sucking type engine. The efficient and compact pre-cooling heat exchanger for the pre-cooling gas sucking type engine comprises a pre-cooling heat exchanger body in the shape of a similar cylinder; the cross section of the similar cylinder is in the shape of a ring different in diameter; the longitudinal section of the similar cylinder is formed by two symmetrically arranged arc segments; the center angle of each arc segment is 45 degrees; the pre-cooling heat exchanger body comprises a cold flow outlet pipe, a cold flow inlet pipe and a plurality of heat exchanging pipes; each heat exchanging pipe is in the shape of an arc; the arc-shaped center angle of each heat exchanging pipe is 45 degrees; and the heat exchanging pipes are distributed into the similar cylinder in a crossed manner. The efficient and compact pre-cooling heat exchanger for the pre-cooling gas sucking type engine can have the engineer realizability on the premise that the heat exchanging effect is guaranteed, so that air incoming flow in front of a gas compressor can be pre-cooled, the high temperature over-running problem of gas compressor blades is solved, the engine thrust is increased, the flight envelop is extended, the welding difficulty is effectively reduced, the frosting blockage problem is effectively solved, the engineer realizability is achieved under the current technology, and after the efficient and compact pre-cooling heat exchanger for the pre-cooling gas sucking type engine is applied to the pre-cooling gas sucking type engine, the engine performance can be substantially improved.

A refrigeration cycle device includes: a first expansion valve that decompresses a refrigerant flowing out of a high-pressure side heat exchanger; an exterior heat exchanger that exchanges heat between the refrigerant flowing out of the first expansion valve and outside air; a second expansion valve that decompresses the refrigerant flowing out of the exterior heat exchanger; a low-pressure side heat exchanger arranged in series with the exterior heat exchanger; a cooler core that exchanges heat between the heat medium cooled by the low-pressure side heat exchanger and air to be blown into a vehicle interior to cool the air; and a controller configured to switch between a heat absorption mode and a heat dissipation mode by adjusting an amount of decompression in each of the first expansion valve and the second expansion valve.

The invention discloses a frostless air handling unit and a proportion-integration-differential control method of the frostless air handling unit. The frostless air handling unit comprises a circulating working return circuit and a controllable silicon power adjuster, wherein the circulating working return circuit is composed of a compressor assembly, a condenser, an electronic expansion valve and an evaporator assembly, the compressor assembly, the condenser, the electronic expansion valve and the evaporator assembly are sequentially connected along the refrigerating fluid flowing direction. When a calculation controller receives an outdoor temperature parameter transmitted by a temperature-humidity sensor and the temperature parameter is lower than 0 DEG C, the calculation controller carries out calculation according to received air temperature and humidity parameters, an air pressure parameter and an evaporator surface temperature parameter, controls the opening degree of the electronic expansion valve according to the calculation results, and adjusts evaporator surface temperature through increase or reduction of the opening degree of the electronic expansion valve. Meanwhile, the controllable silicon power adjuster judges an air suction superheat degree of a compressor through received compressor air suction temperature and air suction pressure, adjusts increase or reduction of electric heater power, and maintains the air suction superheat degree of the compressor to be kept in a preset value range. According to the frostless air handling unit and the proportion-integration- differential control method of the frostless air handling unit, the aim of maintaining safe and high-efficiency operation of the system is achieved.

The invention relates to an outdoor unit of a heat pump type air conditioner. The outdoor unit comprises a shell and a compressor, a heat exchanger and a fan system arranged in the shell. The shell is provided with a first air inlet and an air outlet, the air outlet is corresponding to the fan system, the first air inlet is corresponding to the heat exchanger. The invention is characterized in that: the outdoor unit also comprises a compressor waste heat collection device, the shell is also provided with a second air inlet on the position corresponding to the waste heat collection device; when the outdoor unit works, the waste heat collection device preheats the air which enters through the second air inlet and conveys the preheated air to a plenum box which covers outside the heat exchanger through a heating pipeline, so that the mixed air of the outside air from the first air inlet and the preheated air from the heating pipeline enters into an inner cavity of the plenum box. Compared with the prior art, the outdoor unit improves the air temperature of the heat exchanger so as to avoid frosting of the heat exchanger and overcome the defect that the prior air conditioner needs to close down twice to defrost the heat exchanger to affect the heating effect.

A cogeneration system is disclosed which includes a waste heat recovering heat exchanger for recovering waste heat generated from a drive source when the drive source operates to drive a generator, heating heat exchangers for heating indoor air, and a heat transfer unit for transferring heat from the waste heat recovering heat exchanger to the heating heat exchangers. The waste heat of the drive source can be used to heat indoor air present in an indoor space. Accordingly, it is possible to maximize the efficiency of the cogeneration system, and to heat indoor heat without driving a compressor.