Raypak NH, 0133-4001 WH Heat Exchanger RE-ASSEMBLY, Control Well Replacement, Tube Replacement

HEAT EXCHANGER RE-ASSEMBLY COMBUSTION CHAMBER REMOVAL

1.Heat exchanger water header O-rings should be replaced with new ones.

2.Install in/out and return water headers and install header retainer nuts and torque nuts evenly.

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 cut-off devices (if so equipped).

7.Open water supply and return shut-off valves. Fill heater and water piping system with water. Check heater and piping system for leaks at full line pres- sure. Run system circulating pump for a minimum of 1/2 hour with heater shut-off.

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 panels. Install top holding screws. Install draft diverter and vent piping if so equipped.

10.If gas piping was disconnected, reconnect gas piping 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 operates immediately on the call for heat. The system is ready for operation.

12.Within two (2) days of start-up, recheck all air vents and expansion tank levels.

Fig# 9337

TYPICAL HEAT EXCHANGER CONFIGURATION

To remove combustion chamber you must first have removed the heat exchanger. Unbolt metal combustion chamber retainer from top and remove combustion chamber panels individually.

REFRACTORY PANELS TOP VIEW

CONTROL WELL REPLACEMENT

Remove top, sensing bulb and clip. Collapse well tube at the open and with a chisel, push through into header and remove the well through header. Insert a new well and roll into place. If a roller is not available, solder the well in place with silver solder.

TUBE REPLACEMENT

1.Remove heat exchanger from heater following instructions outlined under HEAT EXCHANGER REMOVAL above.

2.Remove in/out and return headers. Remove "V" baffle from damaged tube.

3.Remove damaged tube by cutting with a hack saw or shearing with a chisel adjacent to each tube sheet.

4.Collapse stub ends in tube sheets using a chisel or screwdriver. DO NOT cut into tube sheet or mar surface in tube hole in any way.

5.Insert replacement tube by inserting the end with the most fins removed in the opening of one tube sheet. Slide tube until the opposite end clears the other tube sheet and fit the tube into the hole.

6.Insert the tube roller into tube opening up to stop, making certain that 1/8" of tube projects beyond the tube sheet.

7.Attach drill to tube roller, holding it straight and level.

Note: Use a 3/8" heavy duty, reversible, electric drill or larger. Proceed to expand tube until tool starts to grab. Approximately 1/2 to 1" of the tool shank will be visible.

8.Reverse drill motor and withdraw tube roller, If necessary wrench out by hand.

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