Nortec Industries GSTC Outdoor, GSTC Indoor Principle Of Operation, A.Combustion System, 10-00

1.PRINCIPLE OF OPERATION

A.Combustion System

(1)The combustion system is based on a fully modulating forced draft combustion air blower, a negative pressure regulated gas valve, and a 100% premix burner. On a call for humidity, the combustion air blower starts and creates a negative pressure across an orifice located at the air inlet.

(2)The blower is energized to purge the system, then the hot surface igniter is activated. During this time the electronic ignition module does a diagnostic check of safety systems including the air-proving switch, which senses the negative pressure at the air inlet orifice. After the function of the safety systems has been verified, the gas valve will open and the gas/air mixture is ignited by the hot surface igniter.

(3)If a flame is sensed by the flame sensor, the gas valve remains open and combustion continues. If a flame is not sensed, the above sequence is repeated to a maximum of three times after which the ignition module will lock out. The gas valve maintains a constant ratio air to gas independent of blower speed or external conditions. This air and fuel is thoroughly mixed in the blower and then forced through the burner ports where ignition occurs.

(4)Hot products of combustion are forced through a baffle inside the heat exchanger and then vented outside. The heat exchanger has a large flat surface to minimize scale build-up and promote scale shedding to the bottom of the tank. This self- cleaning action helps to maintain the efficiency of the heat exchanger while the smooth surfaces allow for easy cleaning when necessary.

(5)The GS 100 has a single removable combustion chamber/heat exchanger. The combustion system is duplicated on larger units with multiple chambers inside a common tank.

Table 1. Technical Data

			UNIT TYPE
SPECIFICATION	GS 100	GS 200	GS 300	GS 400	GS 500	GS 600
Rated Capacity: lbs/hr*	25-105	25-210	25-315	25-420	25-525	25-630
Rated Capacity: kg/hr*	11-48	11-95	11-143	11-191	11-238	11-286
Input BTU/hr max	140,000	280,000	420,000	560,000	700,000	840,000
Input kJ/hr max	41	82	124	165	206	247
Flue Emissions	Low CO (< 10 ppm) and Low (NOx <40 ppm)
GSTC/GSP Rated Amps	1.1	1.9	2.7	3.5	4.3	5.2
Voltage/Phase			208-240/1 Standard
GSTC Outdoor Rated Amps	3.2	4.0	6.9	7.7	10.6	11.5
Voltage/Phase			208-240/1 Standard
GSTC/GSP Rated Amps	2.1	3.7	5.3	6.8	8.4	10
Voltage/Phase			120/1 Standard
GSTC Outdoor Rated Amps	6.3	7.4	13.7	15.2	21.0	22.6
Voltage/Phase			120/1 Standard

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