Raypak 206A, 406A, 407A, 337A, 336A, 207A Heat Exchanger Reversal Procedure Standard Models, Fig. #4

HEAT EXCHANGER REVERSAL PROCEDURE - STANDARD MODELS

1.Remove right and left side access panels (Figure 1).

2.Disconnect wires at high limit, AGS (automatic gas shut-off), and pressure switch on the in/out header (Figure 2).

3.Digital Models: Remove the thermostat tempera- ture sensor by loosening the compression fitting nut (Figure 3). Re-route the sensor to the left side of the heater.

4. Millivolt Models: Remove the temperature sen- sor bulb and retainer clip from the sensor well (Figure 4). Re-route the sensor bulb to the left side of the heater.

5.Remove (12) bolts holding the inlet/outlet and return headers to the tube sheets. Clean off tube sheet area where the gasket seats. Also clean off the header and the gasket. Apply a non-petrole- um-based lubricant to the gasket such as AquaLube. Re-attach the headers to the opposite sides, making sure they are installed in an upright position (Figure 5). Do not over tighten. Torque should not exceed 7 ft/lb.

6.Reconnect high limit, AGS, and pressure switch wires.

7.Digital Models: Insert the tempera-ture sensor in the compression fitting and tighten 1/2 turn past hand-tight.

8.Millivolt Models: Insert sensor bulb and retainer clip into sensor well.

9.Allow for water flow through the heater and check for leaks.

10.Re-attach access panels to the opposite sides.

For ASME Models call your factory representative.

Fig. #4

Fig. #1

Fig. #2

Fig. #3

Fig. #5

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