Bosch GWH C 920 ES Instruction Manual page 43

specifications in Section 3.4, page 20 Combustion
Air Requirements.
4. Cross contamination. Ensure that intake and exhaust
terminations maintain required clearances as stated
in chapter 3.3, page 9. Cross contamination
between intake and exhaust may cause unstable
burner flames and noise.
5. Lack of gas pressure. Inadequate gas pressure will
cause the fuel-to-air mixture (CO
adjustment. This will result in unstable burner flames
and noise. Ensure gas pressure is in accordance with
specifications in Section 3.13, page 29 Measuring
Gas Pressure. A gas pressure reading is needed to
proceed further. Contact your original installer or a
local certified gas technician to obtain this reading.
6. Verify proper CO readings per chapter 6.5, page
2
36. CO adjustments must be done by a certified
2
gas technician with a calibrated combustion gas
analyzer.
6 720 608 836
) to be out of
2
Troubleshooting
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