Gas heat · GUIDE 06
Combustion-analyzer buying guide
For gas heat, the instrument is only useful when sensors, sampling, calibration and interpretation are trustworthy.01
REAL-WORLD SHORTLIST
Good, better, best picks
Typical U.S. street-price ranges are planning estimates, not quotes. Verify the exact model, ratings, included accessories and current price before buying.
Good$650–$900
Bacharach
BTU900 Combustion Analyzer
Best forResidential heating techs entering electronic analysis.
PROS
- O2 and CO measurement
- Residential workflow
- Established manufacturer
DRAWBACKS
- Calibration and sensors are recurring costs
Better$950–$1,350
Testo
testo 310 II
Best forResidential furnace and boiler techs needing documentation.
PROS
- O2, CO, temperature, draft and pressure
- Fast startup
- Service support
DRAWBACKS
- Meaningful annual ownership cost
Best$1,300–$1,700
Fieldpiece
CAT85 Combustion Analyzer
Best forHigh-volume heating professionals using connected reports.
PROS
- Live draft pressure
- Job Link reports
- Field-oriented design
DRAWBACKS
- Premium price and recurring sensor care
02
BUY FOR THE JOB
What to look for
- ✓Measured gases, ranges and resolution suitable for residential and light-commercial work
- ✓A clear fresh-air zeroing and calibration schedule
- ✓Replaceable sensors, filters, water traps, probes and hoses
- ✓Data logging or printing if your company documents commissioning
- ✓Service turnaround and calibration support you can actually access
03
BEFORE YOU TRUST IT
Field-use checks
- 01Inspect the probe, hose, filter and water trap before every test.
- 02Zero in clean outdoor air as the manufacturer directs.
- 03Test only at approved sampling locations and interpret results with the appliance procedure.
- 04Treat unsafe CO, spillage, rollout or draft conditions as stop-and-correct issues.
04
RED FLAGS
What to avoid
- Consumer indoor-air monitors used as combustion analyzers
- Instruments with unavailable calibration or replacement sensors
- Diagnosing from one number without appliance input, draft, temperature rise and venting context
PRIMARY REFERENCE