1. How many times do I pull the handle on the smoke pump tester?
2. What smoke number is considered acceptable?
3. Why doesn't my MZF draft gauge zero out?
4. Can I use the MZF draft gauge to measure positive draft pressures?

You should take 10 slow pulls on the smoke pump tester.

On a newer style flame retention oil fired burner, you should see a zero smoke as long as the O₂ is within acceptable ranges - typically a 5% to 7% O₂ or a 10.5% to 11.5% CO₂ (PMI).

On an older burner, a trace to number 1 smoke is considered acceptable, again as long as the O₂/CO₂ readings are within the manufacturers specifications.

Make sure the bobbie pin which holds the pointer in place during shipping has been removed.

No.  While this instrument has a small scale on the positive (left hand) side of the zero, it was primarily designed to measure negative draft pressures (on the right hand side of zero). 

Back to the Training Room