Hotel Service Unit 4 Watch Responsibilities Q1 – Answer

  1. Describe the method of testing EACH of the following:
    (a) a bilge high level alarm switch;(3)
    (b) a diesel engine cooling water high temperature alarm probe;(3)
    (c) an oil mist detector.(4)

a) Testing a bilge high-level alarm switch (3 marks)

  1. Manually lift the float (or use a test lever if fitted) in the bilge well to simulate high liquid level.
  2. Confirm that the alarm signal is activated at the control panel.
  3. After test, ensure the float returns freely and the alarm resets correctly.

(b) Testing a diesel engine cooling water high-temperature alarm probe (3 marks)

  1. Remove the sensor/probe from the engine (or isolate for testing if in situ).
  2. Immerse the probe in heated water or an oil bath while monitoring the temperature with a calibrated thermometer.
  3. Confirm the alarm operates at the set point (e.g. 85–95 °C depending on manufacturer’s specification) and resets as temperature falls.

(c) Testing an oil mist detector (4 marks)

  1. Use the manufacturer’s built-in test function or insert a calibrated test cell/smoke generator to simulate oil mist.
  2. Check that the detector responds correctly and that alarm signals are transmitted to the control panel.
  3. Confirm the scanning system (if fitted) cycles through all crankcase sampling points.
  4. Record results in the logbook, ensuring any filters, light sources, or sensors are cleaned and maintained as per manufacturer’s instructions.