Service, Maintenance, and Inspection
What you must know
Routine servicing: isolate, inspect, clean, test, reassemble, and re-commission. Check burners, injectors, heat exchangers, flues, seals, ventilation, and safety devices. Know the difference between a service (maintenance) and a safety inspection/check (assessment of current safety). Understand flue flow and spillage testing, CO/CO₂ ratio checks, and when to condemn versus repair. Recognise wear indicators: sooting, corrosion, deteriorated seals, blocked condensate traps. Records and user advice are part of the job.
Traps in questions
- Treating a safety check as a full service, or vice versa.
- Assuming a clean-looking appliance needs no testing.
- Forgetting to re-check flue flow and combustion after reassembly.
- Overlooking condensate traps on condensing appliances - a dry or blocked trap can cause unsafe operation.
Worked example / rule of thumb
Rule of thumb: Service = restore to safe working order; inspection = judge current safety. If a stem asks what to do on finding a deteriorated flue seal during a service, the answer is to make safe and repair/replace before returning to service - not just note it.
Key exam behaviours
Match the task named in the stem (service vs inspection) to the correct scope. Choose "make safe and record" over "monitor" for defects affecting safety.