HEAT EXCHANGER REMOVAL
1.Shut water, gas and electricity off, close valves and relieve pressure, remove relief valve. Re- move side inspection panels.
2.Remove top holding screws.
3.Remove draft diverter, lift and remove top and flue collector on
4.Loosen bolts and disconnect flange nuts on inlet/ outlet header, loosen union(s) at gas pipe and slide boiler away from piping until studs clear the header.
5.Remove combustion chamber clips at the four corners of the heat exchanger.
6.Lift heat exchanger straight up using caution not to damage refractory.
7.Reverse above procedure to reinstall.
CONTROL IMMERSION WELL REPLACEMENT
1.Shut water off to heater and drain heat exchanger.
2.Remove jacket top panel.
3.Remove old control well with bushing and sleeve, with 7/8" wrench or socket.
4.Slip "O" ring gasket over control well and install in header.
"O" RING GASKET
WELL ASSEMBLY
Fig. # 8101.0
UNITHERM GOVERNOR (U.G.) REPLACEMENT
1.Shut water, gas and electricity off, close valves and relieve pressure.
2.Drain heat exchanger.
3.Remove retainer plug located under outlet pipe connection.
4.Remove spring and replace old U.G. with a new U.G.
5.Reverse above procedure to
GASKET
U.G.
RETAINER PLUG
SPRING
FIig. # 8071.0
To test the operation of the Unitherm Governor, place in hot water (over 110 °F) and watch for move- ment against spring. If there is no movement, replace unit.
TUBE CLEANING PROCEDURE (Typical)
Establish a regular inspection schedule, frequency depending on local water condition and severity of service. Do not let the tubes clog up solidly. Clean out deposits over 1/16" in thickness.
The heater must be cleaned from the rear as shown. It is preferable, however, to remove the heat exchanger and the in/out header for better visibility through the tubes and to be sure the
Note that you do not remove the top panel or the heat exchanger, generally.
After reaming, mount the wire brush in place of the auger and clean out debris remaining in the tubes.
Another method is to remove the heat exchanger, ream tubes and immerse heat exchanger in non- inhibited
Fig. # 8128.0
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