WorksheetsHot water supply systems and the associated safety features
Total questions: 26
Worksheet time: 13mins
What is the purpose of a sacrificial anode in a hot water cylinder?
To cool down the water
To act as a safety discharge point
To protect the steel lining of the cylinder
To filter the water
Why is an open-vented system considered very safe if installed correctly?
Because it uses cold water
Because it is under atmospheric pressure
Because it has a filter
Because it is very cheap
By how much does a typical heated hot water system expand?
2%
4%
6%
8%
At what temperature does the temperature relief valve begin to discharge?
70-75°C
80-85°C
90-95°C
100-105°C
What is the purpose of the temperature relief valve in a cylinder?
To increase the temperature
To discharge water when the temperature is too high
To decrease the pressure
To add more water to the cylinder
The temperature relief valve is the third tier of safety in the event of what failures?
Cylinder thermostat and energy cut-off failure
Pressure gauge and water pump failure
Water heater and pipe failure
Thermometer and valve failure
What is the primary function of a line strainer in plumbing?
To increase water pressure
To prevent particles from entering and damaging the pipework
To heat the water
To reduce water flow
What can happen if a line strainer becomes blocked with debris?
It can increase the water temperature
It can cause the pipe to burst
It can affect the flow rate of the system
It can change the color of the water
What does the pressure reducing valve control?
The temperature of the system
The working pressure of the system
The flow rate of the system
The electrical current of the system
Where is the pressure identified on the pressure control valve?
On the system
On the component
On the manual
On the pipe
What is the purpose of a single check valve in plumbing?
To increase water pressure
To prevent backflow into the mains supply
To filter impurities from water
To regulate water temperature
What is the function of an expansion relief valve?
To increase the pressure in the system
To relieve excess pressure in the system
To decrease the temperature in the system
To control the flow of water in the system
When does the expansion relief valve open?
When the temperature of the system is too high
When the design pressure of the system is exceeded
When the system is turned off
When the system is empty
What is the purpose of the expansion valve and the temperature-relief valve in relation to the tundish?
To increase water pressure
To discharge water through the tundish if a fault develops
To heat the water
To filter the water
How must the tundish be installed?
Horizontally within 300mm of the safety valves in a different location from the unvented cylinder
Vertically within 500mm of the safety valves and in the same location as the unvented cylinder
At an angle and behind the water heater
Upside down and away from the unvented cylinder
What components make up a combination valve?
Line strainer, pressure reducing valve, expansion relief valve, non-return/check valve, isolation valve
Line strainer, pressure increasing valve, expansion relief valve, non-return/check valve, isolation valve
Line strainer, pressure reducing valve, expansion relief valve, return valve, isolation valve
Line strainer, pressure reducing valve, expansion relief valve, non-return/check valve, control valve
What is one of the benefits of a combination valve?
They are cheaper than other valves.
They are assembled by the manufacturer and often arrive ready to fit with an appliance.
They are more durable than other valves.
They are easier to clean.
What is the primary purpose of an expansion vessel?
To accommodate the thermal expansion of water and protect the system from excessive pressures
To store water for daily use
To filter impurities from water
To heat water for household use
Where should an expansion vessel be installed?
Securely into a masonry wall using Hex bolts and as close to the storage vessel as possible
At low level from the storage vessel and loosely fitted for maintenance
At the same level as the storage vessel
Below the storage vessel
What is the primary purpose of discharge pipework on unvented hot water systems?
To heat the water
To remove the discharged water safely
To store the water
To filter the water
Why is it important for discharge pipework to terminate in a safe location?
To prevent water contamination
To ensure the water is clean
To avoid damage to the building
To reduce water pressure
What material is recommended for discharge pipework?
Plastic
Copper
Aluminum
Steel
At what temperature is water distributed from the hot water storage system?
60°C
50°C
55°C
45°C
What is the temperature range at which water is delivered to the hot water outlets to ensure user safety?
30°C to 40°C
35°C to 46°C
40°C to 50°C
45°C to 55°C
What device is used to efficiently manage the temperature of water in a hot water storage system?
Isolation valve
Pressure valve
Thermostatic mixing valve
Flow control valve
What are the 3 states of water?
0° Ice
10° Tepid
100° + Gas
0° - 100° Liquid
