Abstract: Apparatus and a method for providing heated replacement air to a paint spray booth or other commercial process which requires heated make-up air to replace exhausted air. A blower draws outside air through a filter and an injection chamber prior to delivering the air to the process. Hot gases from a burner are injected into the injection chamber and mixed with the replacement air to adjust the temperature of the replacement air. The burner uses combustion air which is separate from the replacement air. The flow rate of the exhaust air and the replacement air can be adjusted to meet changing needs of the process. The BTU output from the burner is adjusted to maintain a desired replacement air temperature.

Abstract: Apparatus and a method for providing heated replacement air to a paint spray booth or other commercial process which requires heated make-up air to replace exhausted air. A blower draws outside air through a filter and an injection chamber prior to delivering the air to the process. Hot gases from a burner are injected into the injection chamber and mixed with the replacement air to adjust the temperature of the replacement air. The burner uses combustion air which is separate from the replacement air. The flow rate of the exhaust air and the replacement air can be adjusted to meet changing needs of the process. The BTU output from the burner is adjusted to maintain a desired replacement air temperature.

Abstract: Apparatus and a method for providing heated replacement air to a paint spray booth or other commercial process which requires heated make-up air to replace exhausted air. A blower draws outside air through a filter and an injection chamber prior to delivering the air to the process. Hot gases from a burner are injected into the injection chamber and mixed with the replacement air to adjust the temperature of the replacement air. The burner uses combustion air which is separate from the replacement air. The flow rate of the exhaust air and the replacement air can be adjusted to meet changing needs of the process. The BTU output from the burner is adjusted to maintain a desired replacement air temperature.

Abstract: A self-adjusting damper device is provided for installation into an air-conveying duct to prevent the development of damaging low pressure within the duct. The device utilizes a panel adapted to occlude an aperture in the duct. Springs hold the panel in a position which normally occludes the aperture. The panel travels toward the interior of the duct in response to low pressure within the duct. The extent of travel of the panel is limited by a retaining member.