The Selas AHP series of indirect air heat exchangers are designed for commercial air heating applications. The robust construction of the units makes them an ideal heat source for shopping centers and commercial premises. AHP heaters are usually fitted with a high temperature limit thermostat or thermocouple unit, in order to protect the heat exchanger from excessive overheat.
The standard AHP heaters consist of a heat exchanger module with combustion chamber, primary tube bank and a two pass economizer section. The heat exchanger section is generously rated for heat transfer surface area; a transfer rate of 12.62 kW. Per M3 has been used for the design. The combustion chamber and the tube banks are manufactured using high-grade stainless steels and both the chamber and tube bank assembly are independently mounted to cater for differential expansion. The outer casing of the AHP unit is manufactured from standard carbon steel and is of an uninsulated construction. The complete inner assembly can be withdrawn on the front plate for repair or servicing, and the tube banks are fitted with an end inspection cover.
Each AHP unit is supplied with a pre-packaged and pre-wired burner assembly which includes all of the necessary burner fuel safety valves, pressure switches and automatic ignition and flame safety equipment. Burners supplied are usually of the modulation type however burners built to application specifications and country of installation can be fitted. All Burner packages are fully tested and the operation of all components are checked before dispatch from the factory.
Burners can be fitted for operation with natural gas; LP gases or light fuel oils. All gas burners are sized to suit an inlet gas pressure of 17.5mbar (natural gas) or 30mbar (LP gases) unless otherwise specified. Burners can be supplied to suit other fuel types and supply pressures.
Direction of Air Flow
Standard AHP heaters are arranged to fire horizontal in the direction of airflow from left to right. (SF) Heater units can be supplied for firing into duct systems with vertical upward or downward flow. Airflow should be uniform across the air duct, both upstream and downstream of the heater.
The AHP units can be fitted with burners to suit almost all types of electrical supply, including all common industrial three phase (50 or 60Hz) power supplies and with 110/120v or 220/240v control circuits. Burners to suit other electrical voltages can be supplied for specific application requirements.