Page 19
3- Disconnect supply gas piping.
4- Remove screws holding burner box damper in place
and remove burner box damper assembly and dampĆ
er prove switch cover.
5- Remove screws securing removable burner box top.
6- Remove screws holding gas manifold in place and
pull burners from heat exchanger.
7- Remove baffles inside top opening of heat exchanger by
twisting tabs too align with slots in baffles.
8- Insert a 2 ft. (600 mm) steel rod that has a 20 in. (508
mm) length of chain attached to one end into top
opening of heat exchanger. See figure 28.
CLEANING HEAT EXCHANGER
Connect chain to rod and drop chain
down through top of heat exchanger.
Connect at bottom to another rod.
Move rods up and down, back and
forth to clean heat exchanger.
FIGURE 28
9- Shake rod to drop chain through the clamshell into
burner cavity in bottom of heat exchanger.
10- Attach bottom of chain to another 2 ft. (600 mm) rod.
11-Push and pull the rods back and forth and up and
down with a vigorous motion. The chain will dislodge
the soot and scale deposits inside the heat exchangĆ
er. Repeat for each clamshell.
12-With a shop vacuum or rags, clean out soot and scale
deposits from bottom of heat exchanger.
To clean burners:
NOTE-FOR UNITS WITH FLAME RODS, remove two
springs and withdraw rods from back of burner. Clean
flame rods with wire brush. Continue with items 13
through 15 below and reinstall flame rods and springs.
13-Clean top of burner ports with a wire brush. See figĆ
ure 29.
14- Clean burner ports by inserting a cleaning tool (made
from a piece of sheet metal cut to fit the burner ports) and
work in and out of each port. See figure 30.
15-Clean inside of each burner with a bottle cleaning
brush. See figure 31.
CLEANING TOP
FIGURE 29
CLEANING PORTS
FIGURE 30
CLEANING INSIDE
FIGURE 31
16-Replace burners making sure to fully engage in rear
receiving slot in heat exchanger. Resecure gas manĆ
ifold and supply piping.
17-Reinstall baffles inside top opening of heat exchanger
twisting tabs to secure baffles.
18-Resecure damper assembly, damper prove switch
cover and burner box top. Carefully open damper by
hand to ensure that the damper spring closes damper
correctly and that the damper prove switch is enĆ
gaged when damper is open.
CAUTION
Use extreme care when opening damper door to
prevent permanent damage to the damper motor.
19- Before replacing draft hood, flue pipe and access panels,
inspect draft hood gasket. Replace gasket if necessary.
20-Carefully check all piping connections (factory and
field) for gas leaks. Use a leak detecting solution or
other preferred means.
CAUTION
Some soaps used for leak detection are corrosive
to certain metals. Carefully rinse piping thoroughly
after leak test has been completed. Do not use
matches, candles, flame or other sources of igniĆ
tion to check for gas leaks.
21-Turn on gas and electrical supply.
