QUESTION 12
The following six items relate to a mains pressure valve vented electric hot water system.
Explain the purpose of each item and how it functions.
(a) Pressure limiting or pressure reducing valve.
 Purpose:
 How it functions:
(2 marks)

(b)  Filter.
 Purpose:
 How it functions:
(2 marks)

(c) Thermostat.
 Purpose:
 How it functions:
(2 marks)

(d)  Energy cut out device.
 Purpose:
 How it functions:
(2 marks)

(e) Cold water expansion valve.
 Purpose:
 How it functions:
(2 marks)

(f) Temperature and pressure relief valve.
 Purpose:
 How it functions:
(2 marks)
Total 12 marks

Linkback: https://www.plumbers.nz/plumbing-exam-june-2008/22/question-12/111/