Installation Instructions Gas Conversion Kit For models: 250 SX, 250 SXO, GWH 2400 E, GWH 2400 EO, GWH 635 ES, GWH 635 ESO, GWH 715ES, GWH 2700 ES, GWH 2400 ES, Evolution 500, 830ES, 940ES, 940ESO Part. no 8 719 002 176 6 720 607 679 (2009/05) US Warning: This kit shall be installed by a qualified service agency in accordance with these instructions and all applicable codes and requirements of the authorities having jurisdiction.
Gas Type Conversion 1 Gas Type Conversion For models: 250SX, 250SXO, GWH 635 ES, GWH 635 ESO, GWH 2400 E, GWH 2400 EO only LP AND NG ARE EXTEMELY FLAMMABLE SO TAKE EXTRA PRECAUTIONS WHEN PERFORMING ANY WORK TO THE HEATER. i PROCEDURE MUST BE PERFORMED BY A LICENSED GAS TECHNICIAN. Fig. 2 A. Preparation B 7. Remove yellow painted # 40 Torx cover from the front of the gas valve revealing a plastic #40 Torx screw (Fig. 3). B 1.
Gas Type Conversion B. Converting from LPG to NG B 1. Add jumper to location JP6 on the control board (Fig. 4). 6720607679-11.1AL Fig. 4 B 2. Turn slotted brass screw 3.5 turns counter clockwise (Fig. 2). B 3. Turn #40 plastic torx screw 1 tooth clockwise (Fig. 3). B 4. Adjust CO2 (see chapter 2). C. Converting from NG to LPG B 1. remove jumper from location JP6 on the control board (Fig. 4). B 2. Turn slotted brass screw 3.5 turns clockwise (Fig. 2). B 3.
Measuring and adjusting CO2 levels 2 Measuring and adjusting CO2 levels The CO2 can only be adjusted by a certified gas technician with a calibrated CO2 analyzer. Caution: One factor that may affect CO2 levels is improper gas pressure. Please see Chapter 2.12 of manual for the procedure to measure gas pressure and record your findings below: Static Gas Pressure: " WC P1 Operating Pressure: " WC The P1 minimum operating pressure is 5" WC for Natural Gas and 11"WC for Propane.
Measuring and adjusting CO2 levels D. Returning to Service: 1. Return slotted cover to original position. 2. Reinstall Torx cover. 3. Remove CO2 analyzer probe and reinstall flathead screw with gasket in exhaust collar. 4. Turn ON/OFF switch to the OFF (O) position and then back to the ON (I) position. 5. Heater is ready for normal operation. Without Front Cover With Front Cover Nat. Gas Nat. Gas max. input P1 9.1 ± 0.1 % 9.7 ± 0.1 % min. input P2 9.4 ± 0.1 % 9.7 ± 0.1 % LP Gas LP Gas max.
Gas Type Conversion 3 Gas Type Conversion B. Converting from LPG to NG For models: GWH 2400 ES, GWH 2700 ES, GWH 715 ES, Evolution 500, 830ES, 940ES, 940ESO only. B 1. Add jumper to location JP6 on the control board (Fig. 11). LP AND NG ARE EXTREMELY FLAMMABLE. TAKE EXTRA PRECAUTIONS WHEN PERFORMING ANY WORK TO THE HEATER. i PROCEDURE MUST BE PERFORMED BY A LICENSED GAS TECHNICIAN. A. Preparation 6720607679-06.1AL Fig. 11 LPG to NG B 1.
Gas Type Conversion Operating Gas Pressure Test Model B Press ON/OFF button to turn off the appliance. B Press and hold "Program" (P) button and press ON/ OFF button to turn appliance ON. Fig. 13 B As soon as '188' is displayed, release "Program" , button and the display should read P2.
Gas Type Conversion A. Once Gas Pressure is adequate B Press ON/OFF button to turn off the heater. B Record the CO2 reading in P1 below. (Analyzer reading may take several minutes to stabilize). B Remove brass flat head screw on the exhaust collar as seen in Fig. 5. B Press the ‘ ’ button until P2 appears. Unit will ramp down to low fire and the flow should decrease. B Insert CO2 analyzer probe into the measuring port. The tip of the probe should be in the center of the flue pipe (approx 1.
Gas Type Conversion C. Adjusting CO2: 2. If P2 CO2 level is off: Note: P1 adjustment will change the P2 reading. Confirm the P1 value BEFORE adjusting the P2 level. B Remove yellow painted #40 Torx cover from the front of the gas valve. (Fig. 18, pos.1) A plastic #40 Torx screw will be revealed. 1. If P1 CO2 level is off: B Loosen yellow painted philips screw (1) and cover should rotate down (2) revealing a recessed brass slotted screw. Fig. 17.
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Replacement Parts available from: BOSCH THERMOTECHNOLOGY CORP. 50 Wentworth Avenue Londonderry, NH 03053 Tel. 866-330-2730 www.boschpro.com Recycled paper Bosch Termotecnologia SA Estrada de Cacia 3800 - 533 Cacia - PORTUGAL © 2010 Bosch Thermotechnology Corp.
