Lennox KGC Series Unit Information page 22

D-GAS HEAT COMPONENTS
KGC units are available in 130,000 BTUH (38.1 kW),
180,000 BTUH (52.7 Kw) or 240,000 BTUH (70.3 kW)
heat sizes.
1-Heat Exchanger (FIGURE 11)
The KGC units use aluminized steel inshot burners with
matching tubular aluminized steel heat exchangers and
two-stage redundant gas valves. Units use two six tube/
burners for standard heat, two nine tube/burners for
medium heat and two eleven tube/burners for high heat.
Burners in all units use a burner venturi to mix gas and
air for proper combustion. Combustion takes place at
each tube entrance. As hot combustion gases are drawn
upward through each tube by the combustion air inducer,
exhaust gases are drawn out the top and fresh air/gas
mixture is drawn in at the bottom. Heat is transferred to
the air stream from all surfaces of the heat exchanger
tubes. The supply air blowers force air across all surfaces
of the tubes to extract the heat of combustion. The shape
of the tubes ensures maximum heat exchange.
The gas valves accomplish staging by allowing more or
less gas to the burners as called for by heating demand.
HEAT HEAT
EXCHANGER EXCHANGER
TUBE TUBE
COMBUSTION COMBUSTION
AIR INDUCER AIR INDUCER
GAS VALVE GAS VALVE
BURNER BURNER
FIGURE 11
HEAT EXCHANGER HEAT EXCHANGER
(one heat section shown) (one heat section shown)
VENT VENT
CONNECTOR CONNECTOR
2-Burner Box Assembly (FIGURE 12)
The burner assembly consists of a spark electrode,
flame sensing electrode and gas valve. Ignition board A3
controls all functions of the assembly.
Burners
All units use inshot burners. Burners are factory set and
do not require adjustment. A peep hole with cover is
furnished in the heating access panel for flame viewing.
Always operate the unit with the access panel in place.
Burners can be removed individually for service. Burner
maintenance and service is detailed in the SERVICE
CHECKS section of this manual.
Orifice
Each burner uses an orifice which is precisely matched
to the burner input. The orifice is threaded into the burner
manifold. The burner is supported by the orifice and will
easily slide off for service.
NOTE - Do not use thread sealing compound on the orific-
es. Using thread sealing compound may plug the orifices.
Each orifice and burner are sized specifically to the unit.
Refer to Product Zone @ www.davenet.com for correct
sizing information.
BURNER BOX ASSEMBLY
GAS
VALVE
(GV1), GV3)
SPARK
ELECTRODE
GAS MANIFOLD
Page 22
FLAME
ROLLOUT
LIMIT
(S47), (S69)
BURNERS
FLAME
SENSOR
FIGURE 12