MODEL 200-AO
COIL REPLACEMENT PROCEDURE
SEE FIGURES VI & XXVIII
Replacing the coil is a major repair procedure and should not be attempted in other than regular shop facilities
It is further recommended that the following insulation also be replaced during this procedure.
Part No.
Description
Item:
1.
1014-2-05
Insulation, Strip, 3" x 54" x 1"
2.
1014-3-05
Insulation, End, 16" Dia. x 1/2"
1014-4-05
3.
Insulation, Strip, 6" x 54" x 1"
Before attempting this repair, make certain all service (Electric & Water) has been
secured and the system relieved of all pressure. FAILURE TO DO SO COULD RESULT IN
SEVERE OR POSSIBLE FATAL INJURY TO PERSONNEL.
1.
Removal of End Bell Housing:
a)
"Match" mark Bell Housing prior to removal to assure proper alignment when replacing. Remove
the three (3) #8 x 1/2" Hex Head-Slotted Self-Tapping Screws equally spaced around periphery of
Coil Shell.
b)
With suitable mallet inserted through Heater Shell vent opening, tap around the periphery of
of the Bell Housing being careful not to dent nor bend the Insulation Retainer Assembly. When
removed, set aside.
2.
Removal of Coil Inlet Manifold:
Remove Front Panel, item 10 . Loosen clamp and remove hose, water pump to coil inlet assembly,
a)
at Coil Inlet Assembly, item 6 . Disconnect 1/4" Copper Tubing to Inlet Pressure Gauge at Pressure
Gauge Dampening Valve, item 4 .
b)
In sequence, remove the following: Inlet Pressure Gauge Dampening Valve, item 4 ; Airdome
Drain Valve, item 3 ; Airdome, item 2 ; 1/2" Side Outlet Tee along with the 1/2" x 2" connecting
pipe nipple.
..
c)
From the opposite side, in sequence, remove the bonnet of the Blowdown Valve, item 5 ; and as
a single assembly remove the hose spud, valve body and 1/2" x 4" connecting pipe nipple. The re-
maining 1/2" tee along with its coil connecting 1/2" nipple can now be removed from the Coil Assembly.
3.
Removal of the Coil Outlet Manifold:
a)
Remove the Steam Hose from Steam Hose Outlet Port, item 9 ; loosen pipe mounting clamp and
remove 1/2" x 5-1/2" pipe nipple; from the same Side Outlet Tee remove both the Primary Safety
Relief Valve, item 8 , and Overheat Safety Switch, item 7 , being careful not to damage the switch's
lead wires. Next, remove the Side Outlet Tee along with its 1/2" Dropleg Nipple.
b)
Disconnect the 1/4" and 3/8" Copper Tubes and remove Outlet Pressure Gauge Dampening Valve,
item 11 , and remaining Side Outlet Tee. From the opposite side remove Blowdown Port Assembly with
its connecting 1/2" x 2" nipple. The Coil Discharge Tee l long with its connecting 1/2" nipple can
now be removed from the Coil Assembly.
4.
Pulling the Coil:
a)
If old insulation is to be re-used, gently work 6" Insulation Strip, Part #1014-4-05 from coil
and shell assembly and set aside. Remove Rear Panel, item 12 .
b)
Before coil can be removed, three 1/4-20 x 1/2" Hex Head Self-Tapping Coil Alignment
bolts must be removed; two are located on either side of the heater shell (burner side) slightly
below the horizontal centerline, the third bolt is located at the bottom of the vent end and can be
reached through rear opening between Water Supply Tank, item 13, and Heater Shell.
