WorksheetsDomestic Gas Combustion Workbook
Total questions: 11
Worksheet time: 6mins
The only way for an engineer to confirm if burner combustion is producing excessive amounts of Carbon Monoxide is to?
Make contact with the manufacturer's technical department.
Analyse the products of combustion.
Return the following day and complete a visual check.
Interrogate the customer on the appliance history.
What is the most common cause of incomplete combustion of an open flued appliance?
The primary air ports become blocked due to a build-up of lint, fibres, etc.
The secondary air ports become blocked due to a build-up of lint, fibres, etc.
The burner injector becomes enlarged.
The burner is damaged due to corrosion or heat stress.
An obvious sign of incomplete combustion on an open flue, central heating boiler is?
Explosive ignition.
Yellow flames at the burner.
Carbon monoxide alarm activating.
Signs of spillage at the draught diverter.
The process of stoichiometric combustion is shown in which of the following chemical equations?
CH4 + 2O2 → CO2 + 2H2O.
2CH4 + 3O2 → 2CO + 4H2O.
CH4 + O2 → C + 2H2O.
2CH4 + 5O2 → 2CO2 + 4H2O + O2.
Air is generally taken to consist of?
20 % nitrogen and 80 % oxygen.
20.9 % oxygen and 79.1 % nitrogen.
20.9 % nitrogen and 79.1 % oxygen.
20 % oxygen and 80 % nitrogen.
Battery and mains powered carbon monoxide detectors are now manufactured to?
BS EN 50291.
BS 7860.
BS 5440 -1.
BS 5440 -2.
If CO poisoning is suspected, any person affected must be?
Given medical advice over the phone from NHS direct.
Removed from any room containing a gas appliance and relocated to another room.
Advised that gas appliances should be serviced as soon as possible.
Removed from the contaminated area and relocated to the open air immediately.
What level of CO should cause a carbon monoxide detector to alarm within 3 minutes?
35 ppm.
50 ppm.
100 ppm.
300 ppm.
What type of sensor(s) is/are fitted within a typical portable, flue gas analyser?
Carbon dioxide and oxygen.
Carbon monoxide.
Oxygen.
Carbon monoxide and oxygen.
Carbon monoxide detectors can be affected by temperatures?
Below 4.4 °C or above than 37.8 °C.
Below 37.8 °C or above than 40 °C.
Below 4.4 °C or above than 100 °C.
Below 4.4 °F or above than 37.8 °F.
Which of the following is a likely cause of vitiation of a room sealed, balanced, fanned draught, combi boiler?
Room air supply is contaminated.
Incorrectly assembled flue.
Partially blocked injector/s.
Fan failure.
