SPECIFICATIONS
Casing – Standard panels shall be 20 gauge galvanized steel, lined with ½ inch thick HT300 Armaflex high temperature insulation, rated +300°F where required. The housing shall be supported by a formed structural base that forms a pan to ensure weather tight construction. Lifting holes shall be provided at the unit base. The module shall have a weatherproof sheet metal roof. As an option, the exterior of the module shall be coated with an epoxy primer and a polyurethane enamel painting system for added protection. Painting system shall be rated to meet a 1500-hour salt spray test.
Access to components shall be provided through a large, tightly sealed and easily removable access panel. Access panels shall be constructed of the same materials as the unit casing and use SEMCO’s standard hardware. The roof of the unit shall also be removable for access to the heat exchanger.
The module is configured for down discharge only. The module is designed to mate to SEMCO model FV Preconditioner with Coil Module packages only.
Heat Exchanger and Burner – Gas Burner Module shall be furnished incorporating Gas-fired Duct Furnace Heat Module(s). The Duct Furnace module shall be indirect fired and comply with the current edition of ANSI Z83.8 Standard for Gas-Fired Duct Furnaces and be a Recognized Component by Intertek Testing Services (ITS / ETL). The Duct Furnace shall have a minimum combustion efficiency of 80%, designed for operation on the positive pressure side of the supply air blower. Gas-fired duct furnace(s) provided shall have a tubular heat exchanger constructed of 18 gauge Type 304L stainless tubes (.047 min. wall thickness) produced to ASTM A249 and (2.25” for sizes 250 to 400 mbh or 2.00” for sizes 125 to 200 mbh) in diameter. Duct Furnace heat exchanger tubes shall incorporate patented integral formed dimple restriction to eliminate noise associated with expansion and contraction of internal flueway baffles during heating cycles. Heat exchanger shall be designed to provide for unobstructed drainage of condensate that occurs in the tubes during cooling operation, where heat exchanger is located downstream of cooling section.
Burner assemblies shall employ patented inshot gas burners, constructed of aluminized steel body and sintered metal flame holder. Inshot burners shall have integral plenum carryovers for consistent crosslighting.
The module employs an integral combustion blower to draw in air for combustion and exhaust products of combustion. Furnace is configured with combustion blower so that combustion zone is under negative pressure.
Controls – Operating / Ignition controls shall provide for:
A pre-purge period sufficient to ensure at least ten (10) complete air changes of heat exchanger prior to a trial for ignition.
High-energy direct spark ignition source and flame proving via flame rod using flame rectification.
Up to three (3) successive ignition trials prior to a lockout with a minimum fifteen (15) second inter-purge time between trials.
Flame failure response time of 0.8 seconds
A post-purge of at least thirty (30) seconds at the end of every heating cycle.
An ignition sequence re-cycle after one (1) hour if thermostat is still calling for heat when a lockout occurs.
An alarm capable contact to allow for indication of a lockout condition.
Each gas manifold shall include a integral 1/8” NPT tapped test gauge connection for measuring gas pressure to the main burners and a union fitting upstream of the controls to facilitate installation and servicing of gas controls.
Gas controls shall include a combination gas valve with redundant valves and integral pressure regulator, High / Low operators for two stage operation with high and low regulator adjustment and a modulating control valve for modulating systems.
Gas Burner Module is available in either natural gas or L.P. (propane) fuel sources.
Control Options – The Gas Burner Module shall employ a two-stage control system capable of a proven low-fire ignition sequence that minimizes the noise associated with cold start conditions. On a call for first stage or first and second stage heat by the thermostat or controller, the burner control system shall initiate a low fire start sequence at 55% of its maximum input rating.
or
The Gas Burner Module may employ a full modulation system capable of continuous modulation over a range of 25% to 100% of full input. The modulation system shall employ the low fire start ignition sequence as noted above. 0 – 10VDC Analog input by others.
Sole and Exclusive Warranty – SEMCO warrants to Buyer that for a period of eighteen months from the date of shipment by SEMCO the goods to be delivered to Buyer will in all material respects be free from defects in material and workmanship when used in a proper and normal manner. Should any failure to conform to the above appear within eighteen months after the date of shipment by SEMCO (the “Limited Warranty Period”), SEMCO agrees upon prompt notification thereof during the Limited Warranty Period and confirmation to SEMCO’s satisfaction that the goods have been stored, installed, operated and maintained properly and in accordance with standard industry practice, to correct the non-conformity at SEMCO’s option either by repairing any defective part or parts or by making available at SEMCO’s plant a repaired or replacement part.
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