WorksheetsGreenies P2 practice
Total questions: 50
Worksheet time: 25mins
Which gas law predicts that as the pressure of gas in a sealed cylinder increases, at a constant temperature, its volume decreases?
Boyle’s law.
Charles’ law.
Fourier’s law.
Ohm’s law.
At what temperature does water boil at sea level, in kelvins?
100 K
273 K
293 K
373 K
What method of heat transfer is shown in Figure 1 to heat the hot water cylinder?
Radiation.
Conduction.
Expansion.
Convection.
What would happen when increasing the pipe diameter within a system with a constant water pressure supply?
A decrease in the system volume at the highest point.
A decrease in the velocity of water after the pipe diameter is increased.
An increase in the system volume at the lowest point.
An increase in the pressure of water after the pipe diameter is increased.
Where all systems have the same pipework lengths, which plumbing system would create the least resistance to the flow of water?
15 mm diameter pipe, with 1 elbow and 4 machine bends.
15 mm diameter pipe, with 2 elbows and 3 machine bends.
15 mm diameter pipe, with 3 elbows and 2 machine bends.
15 mm diameter pipe, with 4 elbows and 1 machine bend.
What is the electrical current in a 230V circuit with a resistance of 57.5 ohms?
0.25 amps.
4.0 amps.
13.25 amps.
16.0 amps.
Calculate the fuse for a 4.5kw water heater on 230v mains electricity.
16-amp fuse.
20-amp fuse.
32-amp fuse.
45-amp fuse.
Which fluid category is wholesome water supplied to domestic dwellings?
1
2
3
4
What is an advantage of installing an indirect cold water system in a domestic property?
It is the cheapest system for labour, material costs and maintenance.
A reserve of water in the cold water storage can be used as a backup.
It is the best system to achieve high pressure at all draw-off points.
Provides wholesome water to all draw-off points within the property.
What are the minimum pipe sizes used on an indirect cold-water system?
12 mm for the rising cold main pipe 22 mm for the cold distribution pipe.
15 mm for the rising cold main pipe 28 mm for the cold distribution pipe.
15 mm for the rising cold main pipe 22 mm for the cold distribution pipe.
18 mm for the rising cold main pipe 28 mm for the cold distribution pipe.
Where must a single impeller shower pump be installed on a shower mixing valve?
On the distribution cold supply to the shower mixer valve.
Between the shower mixer valve and the shower head.
On the mains cold supply to the shower mixer valve.
Between the cold-water storage cistern and the shower mixer valve.
What type of float-operated valve incorporates a flow restrictor to overcome issues of water hammer in a property with high water pressure?
Part 1
Part 2
Part 3
Part 4
What is the minimum clearance above a cold water storage cistern for maintenance and cleaning?
250 mm
300 mm
350 mm
400 mm
Why is it necessary to insulate pipework and cold water storage cisterns?
To prevent freezing and thermal expansion.
To prevent freezing and thermal transfer.
To prevent thermal transfer and expansion.
To prevent thermal transfer and corrosion.
Which Building Regulations include a water efficiency calculator?
Part G
Part H
Part L
Part P
Which statement correctly describes back siphonage in a cold water system?
The water flow in the opposite direction is due to higher pressure in the downstream system.
An incident causing water to be drawn from a plumbing system into the mains water supply.
Intermittent water flow due to air pockets in the plumbing system, causing water supply problems.
An increase in water pressure, causing leaks in the mains cold water system and flooding.
Which appliance must have an AUK1 air gap incorporated into the installation?
Shower head.
WC toilet.
Over-the-rim bidet.
Wash hand basin.
Under the Water Regulations, what component must be installed on a mixer tap that mixes the water in the tap body?
Double check valve.
Reduced pressure zone valve.
Single check valve.
Isolation valve.
What are the operating principles of a Single feed, indirect (primatic) hot water cylinder?
The cylinder has a coil separating the secondary water from the circulating primary water.
The cylinder uses an air entrapment to separate the primary and secondary water.
The cylinder has a coil separating the primary water from the circulating secondary water.
The cylinder uses the water circulating from the heat source to distribute to the taps.
According to Approved Document G3, what should be installed when fitting a new bath?
Anti-Legionella valve.
Temperature relief valve.
Pressure reducing valve.
Thermostatic mixing valve.
How does a negative head shower pump work?
The pump flow switch operates when water starts flowing from the storage cistern to the shower pump.
The pump operates once a wireless signal has been received from the shower which opens and closes the solenoid valve.
The pump pressure switch operates the pump once pressure is released through the opened shower mixer valve.
The pump has a suction device and operates through a specially designed shower mixer valve.
What type of pump must be installed on a secondary return on a hot water system?
Bronze centrifugal pump.
Bronze rotary pump.
Steel centrifugal pump.
Steel rotary pump.
What are the minimum requirements when constructing a platform made from marine plywood to support a cold water storage cistern that measures 1000 mm × 1000 mm?
The platform supporting the cistern must have a minimum thickness of 12 mm and dimensions of 1000 mm × 1000 mm.
The platform supporting the cistern must have a minimum thickness of 15 mm and dimensions of 1100 mm × 1100 mm.
The platform supporting the cistern must have a minimum thickness of 18 mm and dimensions of 1200 mm × 1200 mm.
The platform supporting the cistern must have a minimum thickness of 21 mm and dimensions of 1300 mm × 1300 mm.
In Figure 2, which letter identifies the position of the Pressure reducing valve?
A
C
D
E
Which Building Regulation document details the legal requirements for domestic hot water systems?
Approved Document F.
Approved Document G.
Approved Document H.
Approved Document M.
A customer has complained about lukewarm water coming from the cold tap. On close examination by an operative, it is clear that the hot water storage system is unvented. What is the cause of the problem and how would it be resolved?
Back pressure has occurred because the check valve has failed, allowing the hot water to expand in the pipe. The check valve will need to be replaced.
The expansion vessel is undersized, meaning that expansion must have taken place within the cold water system. A correctly sized expansion vessel will need to be installed.
Back siphonage has occurred; this happens when the tap is opened too quickly, causing negative pressure. An anti-vac valve will need to be installed.
The seating on the pressure release valve has become stuck, preventing pressure from leaving the system. The relief valve will need to be cleaned or replaced.
Which risk category permits only an air gap to act as protection against contaminating the mains water supply?
Category 2
Category 3
Category 4
Category 5
What backflow prevention should be used on a washbasin where the tap outlets are below the spillover level?
Single check valve.
Inline pipe interrupter.
Reduced pressure zone.
Double check valve.
What is a disadvantage of a gas-fired gravity hot water and pumped heating system?
The heating cannot be operated independently from the hot water.
The system requires a higher volume of water to operate hot water and heating efficiently.
The hot water cannot be operated independently from the heating.
The system lacks temperature controls which causes both hot water and heating to overheat.
What is the minimum size of pipework required on a pumped heating gravity hot water system?
15 mm heating primary flow and return with 22 mm pipework used for the gravity hot water cylinder.
22 mm heating primary flow and return with 22 mm pipework used for the gravity hot water cylinder.
22 mm heating primary flow and return with 28 mm pipework used for the gravity hot water cylinder.
28 mm heating primary flow and return with 22 mm pipework used for the gravity hot water cylinder.
What pipe sizes are used on a microbore system, including the size of the heating manifolds?
8 mm and 10 mm pipe connected to a 15 mm manifold.
10 mm and 15 mm pipe connected to a 15 mm manifold.
8 mm and 10 mm pipe connected to a 22 mm manifold.
10 mm and 15 mm pipe connected to a 22 mm manifold.
Which boiler incorporates a diverter valve and a plate heat exchanger?
Back boiler.
Combination boiler.
Heat only boiler.
System boiler.
Which component is included when installing a sealed central heating system?
Feed and expansion cistern.
Composite valve.
Expansion vessel.
Limiting valve.
What is the purpose of the component in Figure 3?
Assist circulation in the heating system.
Remove air from the heating system.
Remove iron oxide from the heating system.
Relieve pressure in the heating system.
A heating engineer is required to diagnose an issue with a fully pumped central heating system. The upstairs radiators and the hot water flow and return pipes to the upstairs hot water cylinder are lukewarm. The downstairs radiators are cold. What actions should be taken by the heating engineer, from start to end?
Check circulation, by examining the pump. If power is present at the pump control box but the impellers are not rotating, carry out safe isolation and change the pump.
Check the automatic bypass. If it fails to open to relieve pressure, drain the system and replace it. On completion, operate the system and carry out functional testing.
Check the programmer by operating the thermostats. If power is not present at the thermostat to operate the system, carry out safe isolation and change the programmer.
Check the water content in the system. If there's insufficient water in the system, safely isolate the water supply and repair or replace the feed and expansion system.
What allows the flow rate of water to be maintained through a multi boiler installation without disturbance from any other heating circuit?
Low loss header.
Manifold header.
Reverse return header.
High loss header.
A customer has heating but no hot water. The programmer is working correctly. The operative inspects the system and determines that power is present between the wiring centre and the cylinder thermostat. What work should be undertaken to repair the system and make it operational again?
Use tools and test equipment conforming to GS38 to test the orange wire. If 230v is present, carry out a safe isolation procedure and replace the pump.
Use tools and test equipment conforming to GS38 to test the grey wire. If 230v is not present, carry out a safe isolation procedure and replace the zone valve.
Use tools and test equipment conforming to GS38 to test the brown wire. If 230v is present, carry out a safe isolation procedure and replace the cylinder thermostat.
Use tools and test equipment conforming to GS38 to test the orange wire. If 230v is not present, carry out a safe isolation procedure and replace the valve head.
What is the purpose of the component in Figure 4?
To limit the flow rate when balancing a full central heating system.
To open and allow circulation when flow restriction occurs.
To divert heat at a given temperature, to ensure radiators are not too hot.
To ensure the system is automatically filled when the pressure drops.
According to the Building Regulations, what are the requirements for a floor area that exceeds 150m2 ?
Every radiator must have a thermostatic radiator valve and a wireless room thermostat.
Every room exceeding the 150 m^2 floor area must have programmable room thermostats.
A floor area exceeding 150 m^2 must have its own zone valve with a programmable thermostat.
A floor area exceeding 150 m^2 must be notified to building control during their visits to the site.
When positioning and fixing pipework below suspended timber floors, what requirement must be met?
Pipework is accessible for insulation when installation is complete.
Pipework is easily accessible, using removable access hatches.
Pipework is spaced 150mm apart for air circulation.
Pipework is mechanically protected below the floor.
Where are the maintenance requirements for a condensing combination boiler located?
Manufacturer’s brochure.
British Standards.
Manufacturer’s instructions.
Approved documents.
Which stack system accommodates multiple appliances at extended distances from the stack?
Primary ventilated stack system.
Vented Stub stack system.
Secondary ventilated stack system.
Ventilated branch discharge system.
What is the minimum requirement when installing a branch discharge pipe serving a bath in a domestic dwelling?
32 mm waste pipe no more than 3 m
40 mm waste pipe no more than 3 m
50 mm waste pipe no more than 4 m
65 mm waste pipe no more than 4 m
When installing a sanitary appliance, an operative realises the waste pipe will exceed the allowed distance from the soil stack. What would solve this problem?
Using a waterless trap.
Using a larger diameter trap.
Using a smaller waste pipe.
Using a larger waste fitting.
A customer has had building work done on a garage, which involved a new rainwater pipe connection to low-level guttering. Since the building work was carried out, the customer has noticed a foul smell in the area. What is the most likely cause of this issue and how would this be resolved?
The rainwater pipe has been accidentally connected to the combined drainage system. A trapped gully will need to be installed.
The rainwater pipe has damaged the below ground pipework. It needs to be excavated and a band seal adaptor should be installed.
The rainwater pipe has been accidentally connected to the combined drainage system. An external vent pipe will need to be installed.
The rainwater pipe has been accidentally connected to the surface water system without a rubber seal. A rubber seal adaptor will need to be installed.
What is the main method used for connecting soil and waste systems in domestic properties?
Snap lock.
Push-fit.
Silicone seal.
Press-fit.
Other than uPVC, what materials are commonly used for rainwater systems?
Copper and lead.
Lead and cast iron.
Copper and aluminium.
Cast iron and aluminium.
An operative has been tasked with replacing the front guttering on a mid-terrace house. The customer would like Ogee Profile guttering, but the properties on either side have half-round cast iron guttering. What should be done to carry out the work?
Use a specialist glue to bond materials whilst allowing for expansion.
Replace the gutter on both sides of the customer's house, because of the material difference.
Use specialist unions to connect the gutters on both sides of the customer's house.
Take moulds of the profiles for the gutters on each side of the customer's house to fabricate a section.
A customer has recently had new guttering installed. After a period of extremely hot weather, thunderstorms occurred, and water started pouring from a gutter union. On close examination, an operative determines that the guttering has detached from the gutter union. How should this problem be resolved?
The length of guttering needs to be shortened, as there is no allowance for expansion. The operative should refit and test.
The guttering must be replaced with a longer piece, as expansion could not take place. The operative should refit a new section and test.
The guttering has too many facia brackets which affects the expansion. The operative should reduce the fascia brackets, refit and test.
The guttering requires debris to be removed as this has prevented expansion. The operative should clean, refit and test.
Which Building Regulation document is required when undertaking work on rainwater systems?
Approved Document J.
Approved Document M.
Approved Document P.
Approved Document H.
