WorksheetsHot water system | Quiz
Total questions: 20
Worksheet time: 10mins
What is the minimum recommended distribution temperature of hot water supplied by a storage cylinder?
48°C
55°C
60°C
65°C
Which Building Regulation relates to the hot water delivery systems in dwellings?
Part F
Part G
Part P
Part L
Which of the following is classed as a localised hot water system?
Under-sink single point heater
Thermal store
Combination boiler
Open vented
Within an open vented hot water system, which of the following are the correct connection methods for the open vent pipe off the draw-off pipe?
Open vent a minimum of 15mm diameter connected within 450mm of the draw-off connection from the cylinder
Open vent a minimum of 15mm diameter connected within at least 450mm of the draw-off point from the cylinder
Open vent a minimum of 22mm diameter connected within 450mm of the draw-off connection from the cylinder
Open vent a minimum of 22mm diameter connected within at least 450mm of the draw-off point from the cylinder
The safety devices within an unvented hot water cylinder are designed to prevent the water from exceeding which of the following temperatures?
60°C
65°C
95°C
100°C
Where should a secondary return be connected within a hot water storage cylinder?
A quarter of the way down
Halfway down
Two-thirds of the way from the bottom
A quarter of the way up
Identify the components in the unvented hot water system.
1, Strainer
2, Isolation valve
3, Expansion relief valve
4, Check valve
1, Isolation valve
2, Strainer
3, Check valve
4, Expansion relief valve
1, Pressure reducing valve
2, Isolation valve
3, Check valve
4, Strainer
1, Isolation valve
2, Strainer
3, Pressure reducing valve
4, Check valve
What temperature should the temperature relief valve fitted to an unvented hot water storage vessel be set to discharge at
60°C
72°C
90°C
95°C
An unvented cylinder can only be installed by whom?
The customer
IPHE registered plumber
Any person who follows the manufacturer's instructions
A competent person
What material must a secondary circulation pump be made from?
Bronze
Pressed steel
Zinc
Cast iron
What does the 450mm leg from the hot water outlet to the base of the open vent prevent
One pipe circulation
Back flow
Back siphonage
One pipe pull
What is the most likely cause of warm water coming out of the cold water tap when it is first opened up?
The cold feed has been incorrectly installed
The hot and cold pipes are touching
The wrong pipe is insulated
The hot distribution is wrongly sized
What can system noise can be caused by?
Flow of water
Water hammer
Thermal expansion
All of the above
What component is installed inside showers to prevent backflow?
Drain-off valve
Double check valve
Stop valve
Single check valve
If a hot water cylinder does not have a heat exchanger coil and the water is being heated by an immersion heater, what type of cylinder is installed in the system?
Indirect
Radiated
Instananeous
Direct
Where is the expansion in a hot water cylinder taken up?
Cold feed from the cold water storage cistern
Primary flow from the boiler
Hot distribution to the outlets
Primary return to the boiler
A hot water cylinder contains 100 litres of cold water. When heated the water will expand. Approximately how much will the water expand by when heated?
10 L
2 L
4 L
12 L
Where on a domestic hot water cylinder should the cylinder thermostat be located?
Top quarter of the cylinder
Middle of the cylinder
1/3 of the way up the cylinder
Bottom of the cylinder
What does the term "heat recovery" refer to?
The time taken for the boiler to get to temperature
The time taken for a cylinder thermostat to activate the boiler
The time taken for a cylinder of water to get to temperature
The time taken for the primary waters to start heating the heat exchanger coil
On an unvented system, what safety item will be activated if the expansion vessel fails?
Pressure relief valve
Temperature/pressure relief valve
Over heat button
High limit cut out valve
