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PART 5: BASIC SERVICE
5.3 Component Repair and Replacement
(Cont.)
5.3.13 Steam Booster Service
Refer to Fig. 6.16, Part 6, Replacement Parts, for a detailed drawing of the steam booster
assembly. The steam booster consists of three pieces as shown on the next page: the shell
casting into which the straight seamless copper tubes are fitted, the rear header, and the flow
header with two tappings for tank connections. Headers are bolted to the shell casting and sealed
against leaks by heavy gaskets. Where soft water or low percentage of mineral deposits is used,
it should only be necessary to clean the heater tubes annually. No acids are needed to clean the
heater tubes.
NOTE:
A single spiral, fine wire brush, 3/4" external diameter, (Champion P/N 112806),
or comparable is recommended for cleaning the booster heater tubes.
Annual Heater Tube Cleaning
Parts Required:
P/N 112357, Gasket (Return header)
P/N 112356, Gasket (Flow header)
Special Tools Required:
Torque wrench (30 ft/lbs needed)
To clean the heater tubes: Turn off all power,
steam, and water supplies to the booster and
dishwasher.
Refer to Fig. 6.16, Part 6, Replacement Parts.
Note (Item 1), thermostats.
Remove the thermostat covers, mark and discon-
nect the wires. Remove the conduit and fittings.
Mark the location of each thermostat before removal, then unscrew each thermostat from its
piping. Break the unions, (Item 12) and remove the piping assemblies from the booster header.
Remove the eight (8) bolts from each header. Remove the flow and return headers. Inspect the
exposed copper tubes and clean as necessary using the cleaning brush
(Champion P/N 112806). Clean the headers as required.
Install new header gaskets and reassemble in reverse order.
To torque the header bolts:
Refer to the torque sequence diagram to the right.
Torque each bolt in three steps:
1) handtight
2) 20 ft/lb
3) 30 ft/lb
Retorque each bolt to 30 ft/lb after 24 hours.
8 BOLTS
8
1
5
3
7
2 6
4
Bolts = 3/8-16
SA-449
Type 1
Flow header gasket
P/N 112356
Return header gasket
P/N 112357
Steam Booster