The heater may be cleaned from the side opposite the water connections, without breaking pipe connections. It is preferable, however, to remove both headers for better visibility through the tubes and to be sure the residue does not get into the system. Generally, you do not remove the top pan or the heat exchanger .
After reaming with the auger, mount the wire brush and clean out the debris remaining in the tubes. Another method is to remove the heat exchanger, ream tubes and immerse heat exchanger in
Heat Exchanger Removal
1.Shut water, gas and electricity off, close valves and relieve pressure, remove relief valve. Remove side inspection panels.
2.Remove top holding screws.
3.Remove draft diverter, lift and remove top and flue collector on stack type models. Remove inspec- tion panels.
4.Loosen bolts and disconnect flange nuts on inlet- outlet header, loosen union(s) at gas pipe, and slide heater away from piping until studs clear the heater.
5.Remove heat exchanger corner brackets.
6.Remove combustion chamber clips at the four cor- ners of the heat exchanger.
7.Lift heat exchanger straight up using caution not to damage refractory.
Heat Exchanger Re-assembly
1.Heat exchanger water header
2.Install
3.Install the four (4) corner clips between tube sheets and refractory. Replace "V" baffles.
4.Install thermostat sensing bulbs in header wells and replace bulb retaining clips.
5.Install inlet and return pipes in water headers using pipe thread sealant.
6.Install water pressure relief valve, flow switch, and low water cutoff devices if so equipped.
7.Open water supply and return
8.Shut down entire system and vent all radiation units and high points in system piping. Check all strainers for debris. Expansion tank water level
should be at the 1/4 mark and the balance of the tank filled with air.
9.Install flue collector, jacket top and inspection pan- els. Install top holding screws. Install draft diverter and vent piping if so equipped.
10.If gas piping was disconnected, reconnect gas pip- ing system and check for leakage using a soap solution.
11.Check for correct water pressure and water level in the system. Make sure that system pump oper- ates immediately on the call for heat. The system is ready for operation.
12.Within two (2) days of
Combustion Chamber Removal
To remove combustion chamber you must first have removed the heat exchanger. Unbolt metal combus- tion chamber retainer from top and remove combustion chamber panels individually.
Fig. 33: Refractory Panels—Top View
29