Crown Boiler BWF061, BWF095, BWF128, BWF162, BWF195, BWF229 TABLE 9: MINIMUM. VACUUM SWITCH READINGS (in. W.C.)

42

3) Vacuum Switch – This boiler is equipped with a vacuum switch that is designed to prevent burner operation if the

combustion fan does not operate properly or there is a blockage in the vent system. This switch “makes” (permits

burner operation) as the vacuum increases. Figure 40 shows the correct method of reading the switch vacuum. The

vacuums in Table 9 are the minimums required for reliable operation. After the boiler fires, the vacuum will drop for

several minutes before stabilizing. The vacuum shown under “Burners On” in Table 9 is the minimum reading which

should be observed after the vacuum has stabilized. The Table 9 readings correspond to sea level vacuum switch

settings. Consult your Crown representative for possible variations in settings at altitudes over 2000ft.

MODELS BURNERS ON

BWF061, BWF095 -0.57 -0.51

BWF128, BWF162 -0.96 -0.89

BWF195, BWF229 -1.21 -1.14

TABLE 9: MINIMUM. VACUUM SWITCH READINGS (in. W.C.)

DURING

PREPURGE

Contents

Main BWF Series Gas-Fired Fan Assisted Hot Water Boilers INSTALLATION INSTRUCTIONS Boiler Co Models: CROWN Table of Contents I Product Description II Specifications III Before Installing IV Locating the Boiler Page V Air for Combustion and Ventilation For Buildings of Other than Unusually Tight Construction For Buildings of Unusually Tight Construction Page Page VI Venting WARNING TABLE 3: SUMMARY OF VENTING OPTIONS Horizontal Vent System Design TABLE 4: VENT SYSTEM ELBOW EQUIVALENT LENGTHS Page TABLE 5: WALL THIMBLES Page Vertical Vent System Design TABLE 6: CAPS FOR VERTICAL VENT SYSTEMS Page Page Removing an Existing Boiler From a Common Chimney TABLE 7: FIRESTOPS FOR VERTICAL VENT SYSTEMS Vent System Assembly Page Page Page Page Page Page VII Gas Piping VIII System Piping Standard Piping Piping for Special Situations Page Page Page IX Wiring Single Zone Wiring Wiring Variations Page BWF Control System Sequence of Operation Page IX Start-up and Checkout NOTE OPERATING INSTRUCTIONS TO TURN OFF GAS TO APPLIANCE FOR YOUR SAFETY READ BEFORE LIGHTING Page Page X Service and Maintenance Heat Exchanger Cleaning Procedure Service Notes TABLE 8: TYPICAL AND MAXIMUM A CCEPTABLE CO2 AND CO READINGS IN FLUE GAS MODELS BURNERS ON BWF061, BWF095 -0.57 -0.51 BWF128, BWF162 -0.96 -0.89 BWF195, BWF229 -1.21 -1.14 TABLE 9: MINIMUM. VACUUM SWITCH READINGS (in. W.C.) DURING PREPURGE XII Troubleshooting 44 Caution: Read page 43 before attempting to use this chart BWF Troubleshooting Chart BWF Troubleshooting Chart (contd.) Page XI PARTS Page 50MM BURNER COMPONENTS - USED ON INSTALLATIONS ABOVE 2000ft: