Raypak 260-401 manual Repair Section, Heatexchangerremoval

REPAIR SECTION

TUBE CLEANING PROCEDURE (TYPICAL) Establish a regular inspection schedule, the fre-

quency depending on the 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 may be cleaned from the side opposite the water connections, without breaking pipe connec- tions. 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.

Note that you do not remove the top pan or the heat exchanger generally.

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 non-inhibited de-scale solvent.

HEATEXCHANGERREMOVAL

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 inspection 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 corners 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 O-rings should be replaced with new ones.

2.Install inlet-outlet 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 cutoff 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 strain- ers 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 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.

COMBUSTION CHAMBER REMOVAL

To remove combustion chamber you must first have removed the heat exchanger. Unbolt metal combustion chamberretainerfromtopandremovecombustioncham- ber panels individually.

REFRACTORY PANELS TOP VIEW

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