A heat exchanger for ventilating insulated dwellings with minimum internal heat loss, is disclosed. The heat exchanger is characterized by its very low manufacturing cost, its excellent efficiency and its minimum and easy maintenance. The heat exchanger consists of an elongated box-like casing forming two opposite end chambers interconnected by a plurality of longitudinally-extending, thin walled glass tubes. Warm stale and humid air is expelled through the glass tubes from one to the other cham...

An air to air heat exchanger including a core structure defining two air paths and a pair of fans for drawing air through the core in the paths is formed by a frame structure defined by interlocking tubular frame elements and panels closing the faces defined by those frame elements. The panels are of different types providing simple closing panels, baffles, inlet and outlet ducts, fan support panels and others all of which are basically square for positioning in a face defined by the frame eleme...

An air to air heat exchanger particularly for contaminated air from an animal barn or the like includes a core formed by a plurality of thin-walled flexible plastics tubes supported at respective ends in tube sheets. The tubes are held under tension and arranged vertically in parallel rows and columns so that cold fresh air enters parallel to the rows horizontally beneath the upper tube sheet and then moved downwardly along the outside of the tubes to escape horizontally parallel to the rows abo...

A device to increase the efficiency of a conventional, air-to-air heat pump in the heating mode when the outside temperature falls below a selected value comprising a solar evaporator coil in refrigerant flow communication with the refrigerant connecting lines of the heat pump between the indoor condenser and the compressor to supply the additional heating capacity. Means are provided for selectively directing refrigerant through the solar evaporator coil when the temperature of the air surround...

A heat exchanger (10) for transferring heat between intake air and exhaust air is disclosed. The heat exchanger (10) includes a plurality of ducts (11) having open first and second ends (11c and 11d). The ducts (11) are connected in a vertical space relationship to one another defining therewith two sets of channels. A first set of channels (11a) being inside the ducts (11) and a second set of channels (11b) being between the ducts (11). Intake air passes through the first set of channels (11a) ...

An air-to-air heat pump with improved efficiency of operation, and simplicity and economy of construction. Initiation and termination of defrost cycles during heating mode operation is controlled, in addition to the conventional clock timer, by a dual pressure switch responsive to pressure in the outdoor coil, thereby significantly reducing the length of defrost cycles with corresponding improvement in operating efficiency. The direction of refrigerant flow between the indoor and outdoor coils i...

An air conditioner equipped with an air cleaner. In the air conditioner, a dust collector is arranged in an air path located behind a heat exchanger. A dust collecting electrode of the dust collector is combined with a heater for self-cleaning. An opening, which communicates the air path located behind the heat exchanger with the outside, is provided above the dust collector. An open-and-close valve, which is closed during the air conditioning operation and opened in the case where the air clean...

A heat recouperator having a single rotary heat and moisture wheel exchanger uses a random matrix media comprising a plurality of small diameter heat-retentive fibrous material, which provides high thermal efficiency in exchanging heat and moisture between inlet and exhaust air streams.

An air supply system having a multi-cylinder, two-stage air compressor including a pair of low pressure cylinders and a high pressure cylinder. A first intercooler interconnected between the outlet of one of the pair of low pressure cylinders and the inlet of the high pressure cylinder and a second intercooler interconnected between the outlet of the other of the pair of low pressure cylinders. An aftercooler connected to the outlet of the high pressure cylinder for effectively reducing the temp...

An air cleaner and an air filter for removing charged ozone in the air includes an air filter having a carbon filter for adsorbing charged ozone in an air path of the air cleaner and converting ozone adsorbed in the carbon filter to oxygen and carbon dioxide by a chemical reaction. A positive voltage is applied to the carbon filter.