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P99 LOW PRESSURE BOILERS EXAM
2025 BRAND NEW ACTUAL EXAM
WITH ANSWERS.
1. A back pressure relief valve is provided for safety if the -
correct answer -Pressure becomes too great
2. Carbon and hydrogen are - correct answer -Two principal
elements of fuel oil
3. Oil is a liquid fuel and as such - correct answer -Will not burn
4. A red smoky flame is an indication of - correct answer -A lack
of air
5. The manual reset pressuretrol is a control that will shut down
the a steam burner boiler if the - correct answer -Pressure
continues to rise above the operating control settings
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6. The safety or pop off valve is a device used to - correct answer
-Relieve excessive steam pressure
7. The boiler steam pressure gauge shows the steam pressure -
correct answer -Inside the steam boiler
8. The stack switch is the - correct answer -Primary control
9. The aquastat - correct answer -Operates the oil burner for
domestic hot water needs
10. The photoelectric cell is a - correct answer -Flame detection
control
11. The vaporstat is - correct answer -A low pressure; pressure
control mounted on the fan housing and will shut down the
burner if no air for combustion exists
P99 LOW PRESSURE BOILERS EXAM
2025 BRAND NEW ACTUAL EXAM
WITH ANSWERS.
1. A back pressure relief valve is provided for safety if the -
correct answer -Pressure becomes too great
2. Carbon and hydrogen are - correct answer -Two principal
elements of fuel oil
3. Oil is a liquid fuel and as such - correct answer -Will not burn
4. A red smoky flame is an indication of - correct answer -A lack
of air
5. The manual reset pressuretrol is a control that will shut down
the a steam burner boiler if the - correct answer -Pressure
continues to rise above the operating control settings
, Page | 2
6. The safety or pop off valve is a device used to - correct answer
-Relieve excessive steam pressure
7. The boiler steam pressure gauge shows the steam pressure -
correct answer -Inside the steam boiler
8. The stack switch is the - correct answer -Primary control
9. The aquastat - correct answer -Operates the oil burner for
domestic hot water needs
10. The photoelectric cell is a - correct answer -Flame detection
control
11. The vaporstat is - correct answer -A low pressure; pressure
control mounted on the fan housing and will shut down the
burner if no air for combustion exists