PA5 Unit standard 30550/ 30551 LPHWC's

Open Ended

Why is it important for professionals in the plumbing industry to understand regulatory requirements and safety standards when working with low pressure hot water supply systems?

Multiple Choice

Which of the following acts is most directly related to workplace safety in the plumbing industry?

• Building Act 2004

• Health Act 1956

• Health and Safety at Work Act 2015

• Plumbers, Gasfitters, and Drainlayers Act 2006

Multiple Choice

Which NZBC clause specifically deals with water supplies in buildings?

• NZBC Clause G10

• NZBC Clause G12

• NZBC Clause E2

• NZBC Clause B2

Open Ended

Summarize the main requirements of NZ Building Code clause G12 regarding water supply in buildings.

Multiple Choice

Which of the following acts is most directly related to the regulation of plumbers, gasfitters, and drainlayers in New Zealand?

• Building Act 2004

• Health Act 1956

• Plumbers, Gasfitters, and Drainlayers Act 2006

• Water Supplies Protection Regulations 1961

Multiple Select

Which of the following are types of low pressure hot water installations covered in NZBC Clause G12/AS1?

• Low pressure open vented storage water heated system - water tank supply

• Mains pressure sealed system

• Low Pressure Valve – Vented Storage Water Heater System – Pressure Relief Valve

• Free Outlet System (push through)

Open Ended

What factors should be considered when sizing a hot water cylinder for a household?

Multiple Choice

Which component in a low pressure open vented tank fed storage water heated system prevents the system from becoming over-pressurized?

• Overflow pipe

• Storage water heater

• Vent pipe

• Cold water supply

Open Ended

1. Describe the practical benefits of the pressure reducing valve in the low pressure system shown in Fig's 7 & 10 over the tank fed system in Fig 6 G12.

2. How does its placement affect the operation of the water heater system?

Multiple Choice

Where should insulation be applied in an open vented storage water heater system in climates subject to freezing, according to the diagram and text in G12 ?

• On the storage water heater only

• On the vent pipe above the standing water level

• On the cold water supply line

• On the hot water delivery pipe

Multiple Select

Which of the following are functions of a pressure reducing valve in a low pressure water heating system?

• Reduces incoming water pressure

• Prevents backflow

• Regulates water temperature

• Acts as a vacuum breaker

Fill in the Blank

The ___ relief valve is an important safety feature in a vented water heater system.

Open Ended

Q: Maintenance requirements for each valve

Fill in the Blank

The sacrificial anode in a hot water cylinder is typically made of ___.

Multiple Choice

Which component replaces the open vent in a low pressure vented storage water heater system?

• Pressure reducing valve

• Pressure relief valve

• Tempering valve

• Expansion valve

Open Ended

1) Why would you recommend this type of system ?

2) What are the reasons for installing a pressure relief valve in a free outlet system?

Open Ended

Compare the main differences between a low pressure tank feed open vent system and a free outlet system (push through) in terms of safety and maintenance.

Multiple Select

Which of the following are key requirements for header tank installation?

• Accessible for maintenance

• Cover fitted

• Chocked tight to tank

• Pipe work clipped within 100mm of tank

Multiple Choice

Which of the following can be used to supply cold water to a storage water heater according to G12/AS1?

• Water tank

• Pressure reducing valve

• Pressure limiting valve

• All of the above

Fill in the Blank

Storage water heaters supplied by other than a water tank shall include a ___ valve to prevent backflow into the cold-water supply.

-

Multiple Choice

Based on the diagram Fig 14 (G12), what is the purpose of the seismic restraint straps on storage water heaters?

• To prevent water leakage

• To support the heater against earthquake forces

• To increase water temperature

• To reduce water pressure

Multiple Choice

According to NZBC B1.3.2, what is the minimum clearance required between the fitting and the support structure when fittings and pipework are attached to the water heater through the supporting platform or floor?

• 25 mm

• 50 mm

• 75 mm

• 100 mm

Open Ended

Explain the concept of hydraulic gradient and its significance in plumbing systems.

Fill in the Blank

Hydraulic gradient is an imaginary line which determines the available pressure (head) at points above a main delivery pipe. Branch pipes and their outlets should be placed ___ the hydraulic gradient to prevent accumulation of air (air lock).

Multiple Choice

Which of the following design tips help to minimize friction loss and preserve water pressure in a plumbing system?

• Use smaller diameter pipes

• Place the cylinder lower than all outlets

• Minimize pipe bends and long runs

• Install more valves

Multiple Choice

If the head of water in a storage water heater is 7.6 meters, what is the corresponding pressure in kPa at the outlet?

• 7.6 kPa

• 76 kPa

• 0.76 kPa

• 760 kPa

Open Ended

Answer the following questions below related to a Low pressure wet-back system:

Reason for installing​

Open vent requirements​

Maintenance requirements​

Requirements when removing wet-back pipework ? ​