3A Cold Water Storage Cisterns Quiz

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What materials can be used as suitable insulation for a cistern?

Straw boarding or sawdust (correct)

Plastic film or cardboard

Fibreglass or polystyrene slabs (correct)

Wood or metal sheets

What is the primary purpose of a warning pipe in a cistern?

To provide ventilation

To inform the customer of a problem (correct)

To regulate water flow

To act as an overflow pipe

Which method should be avoided when drilling a flexible cistern?

Applying jointing materials

Heating copper pipe (correct)

Using a hole saw

Using a hole cutter

When linking two or more cisterns, where should the float operated valve and warning pipe be located?

In the same cistern Signup and view all the answers

What is a common consequence of incorrect installation of a cistern?

Stagnation of water Signup and view all the answers

What does the float operated valve in a cistern do?

Shuts off the water supply at a specific level Signup and view all the answers

Which practice can help avoid stagnation in a single cistern?

Place the primary outlet opposite to the float operated valve Signup and view all the answers

What type of overflow system do cisterns under 1,000 litres require?

Only a warning pipe Signup and view all the answers

What is the main purpose of the measures required for a cold water storage cistern?

To supply wholesome water Signup and view all the answers

Which of the following is NOT a protective measure required for a cold water storage cistern?

Transparent cover to promote algae growth Signup and view all the answers

What is the minimum height above the top access for maintenance of cold water storage cisterns?

350mm Signup and view all the answers

What is the minimum size for a cold feed supplying cold water to the hot water cylinder?

22mm Signup and view all the answers

Why is the cold feed installed 25mm higher than the cold distribution?

To meet safety requirements Signup and view all the answers

Which material is NOT commonly used for cold water storage cisterns?

Concrete Signup and view all the answers

What is the function of a screened warning/overflow pipe in a cold water storage cistern?

To allow excess water to escape safely Signup and view all the answers

How should the service valve be installed in relation to the float operated valve?

Before the float operated valve Signup and view all the answers

Which type of tap is specifically designed for equal pressure systems?

Mixer tap Signup and view all the answers

What is the primary function of packing gland in a rising spindle tap?

To create a watertight seal Signup and view all the answers

What distinguishes a bi-flow mixer tap from a true mixer tap?

Water does not mix until it exits the tap Signup and view all the answers

Which tap type uses two ceramic disc plates for operation?

Quarter turn tap Signup and view all the answers

What is commonly required to disassemble a non-rising spindle tap?

Circlip pliers and adjustable spanner Signup and view all the answers

What type of taps are specifically noted for being used on baths, basins, and bidets?

Pillar taps Signup and view all the answers

Which valve type is used to maintain control of water pressure and flow?

Isolation valve Signup and view all the answers

What additional feature does a high neck pillar tap provide?

Offers a larger air gap Signup and view all the answers

What is a legal requirement for plumbers in the UK when working with water systems?

Using approved materials, fittings, and appliances Signup and view all the answers

Which valve is specifically designed for use on high-pressure systems?

Screw down stop valve Signup and view all the answers

What function does the drain off valve serve in a plumbing system?

To allow water to be drained out at every low point Signup and view all the answers

Where should a service valve (slotted) be fitted in relation to a float operated valve?

Before the float operated valve Signup and view all the answers

Which isolation valve can be operated remotely using air/water pressure?

Surestop remote stopcock Signup and view all the answers

What is required for the installation of washing machine valves?

They must be fitted prior to the washing machine hose Signup and view all the answers

What typically distinguishes a fullway gate valve from other valves?

Can only be used on low pressure systems Signup and view all the answers

What feature does a screw down stop valve provide in a plumbing system?

Direction of flow controls Signup and view all the answers

What distinguishes a float operated valve of type BS1212 Part 1 from other types?

It operates by a piston action. Signup and view all the answers

Which type of float operated valve allows for water discharge from the top?

Type 2 Signup and view all the answers

What is a key characteristic of the diaphragm operated valve in BS1212 Part 4?

Balances water pressure on both sides. Signup and view all the answers

What is a common cause of water hammer when using float operated valves?

Loose jumper in a stopcock. Signup and view all the answers

What is the purpose of using pressure and flow restrictors in float operated valves?

To aid in slow shutdown and prevent water hammer. Signup and view all the answers

Which float operated valve is referred to as a Portsmouth valve?

BS1212 Part 1 Signup and view all the answers

What material can be used for the float operated valve in BS1212 Part 4?

Brass or plastic. Signup and view all the answers

How can ball murmur caused by float operated valves be minimized?

Reduce the incoming flow at the service valve. Signup and view all the answers

Study Notes

Components Used in Domestic Cold Water

Lesson Intent: Learners will identify components, describe isolation valve locations, write paragraphs on various taps, list cistern parts, and differentiate float-operated valves.

Legal Requirements for Plumbers

UK plumbers must use approved materials, fittings, and appliances.
This is a legal requirement.
Approved products are essential to prevent water regulations issues such as backflow contamination and corrosion.

Isolation Valves

Screw Down Stop Valve: Used on incoming mains, high-pressure only, unidirectional flow.
Service Valve (Slotted): Can be high or low pressure, fitted before a float-operated valve (on specific appliances), unidirectional flow.
Washing Machine Valves: Fitted before the washing machine hose.
Lever Arm Spherical Plug Valve: Can be high or low pressure, unidirectional flow.
Fullway Gate Valve: Only for low-pressure systems. Can have a lock shield.

Activity 1: Labeling Valves

Matching valves to their correct names (Washing machine valve, Tap connector isolation valve, Lever valve, Fullway gate valve are examples).

Surestop Mains Isolation

Surestop is a modern mains isolation method using an air/water pressure system.
Used in the event of a water leak.
Often wired into a control system with a manual valve.

Brass Stopcocks and Surestop Remote Stopcock

Brass stopcocks are often hard to access.
Remote stopcocks provide a simple way to turn off water up to 2 meters away.
The valve works via differential water pressure.

Drain Off Valves

Drain off valves are essential at all low points in a system, positioned directly above the incoming stop valve.
These valves allow water draining out when necessary.

Screw Down and Fullway Valves

Screw down valves are for high pressure systems
Fullway gate valves are for low pressure systems.

Isolation Valves (continued)

Diagram of isolation valves: The diagram shows different types of valves with their components labeled.

Cold Water Storage Cistern Parts

Materials: Plastic, Fibreglass, Asbestos, Galvanized Steel.
Water Regulations: CWSC supplying cold water to appliances, must be capable of supplying wholesome water. Specific protective measures must be included to prevent contamination.

Cold Water Storage Cistern Specifics

Installation:
- Effective inlet control to ensure correct water levels
- Maintenance valves for servicing
- Screened warning or overflow pipes
- Insulated for freezing/warmin
- Protection against contamination
- Must circulate water to prevent stagnation
- Accessible for maintenance and cleaning
Location and Dimensions: Cisterns should be placed with a top access point at least 350mm upwards from the roofline for maintenance.
Outlets: Side outlets 25mm away and bottom outlets 25mm away from the pipework to prevent debris entry.
Pipes: Use of 22mm sized cold feed and distribution pipes is recommended for a low pressure system using a Fullway Gate valve; 25mm dimension for height difference.

Tap Types

Pillar Taps: Bathing/basin/bidet fixtures; 3/4" for baths using 22mm pipe size, 1/2" for basins/bidets with 15mm pipe size.
High Neck Pillar Taps: Kitchen sinks with a long neck to facilitate a larger air gap. ½" tail with 15mm pipe connection.
Bi-Flow Mixer Tap: Single spout taps with split flow for hot/cold.
True Mixer Tap: Allows hot and cold water mixing within the tap body. Only suitable for equal pressure systems.
Bib Taps: Wall mounted taps that often use a back plate elbow, and may be for cleaner sinks or outside taps.

Tap Components

Tap Washer: Used for a waterproof seal on rising spindle taps.
Packing Gland: A part of non-rising spindle to seal water
Ceramic Disc Cartridge: Used in quarter turn taps for efficient turns.
O Ring: Used in tap components to provide a seal/watertight seal.

Key details of the Water Regulations for Cisterns: The Water Regulations specify that a cold water storage cistern supplying cold water to appliances / hot water systems should supply wholesome water. Specific protective measures should be included to avoid contamination.

Cistern Drilling and Materials

Flexible cisterns should use hole saws for drilling, avoiding copper pipe heating that can melt the plastic components and cause leaks later on.
Avoid oil-based materials in jointing.
Rigid cisterns can be cut with hole saws or cutters, ensuring swarf is removed afterward.

Tank Positioning

When cisterns are coupled, the float-operated valve and warning pipe system should be situated in one single tank.
A connecting pipe will be needed in this instance.

Water Stagnation and Installation Placement

Stagnant water is a problem. Install the primary outlet opposite the float-operated valve on a single cistern to reduce water stagnation.

Incorrect and Correct Cistern Installations

Pictures illustrating the consequences (incorrect installation) and example of a correctly positioned cistern.

Float Operated Valves

A float valve in a cistern controls the water supply by stopping at a set water level, utilizing a lever action.
Four types of float valves (with their corresponding materials) were outlined.
Different float valves' designs can have variations in water discharge locations.
Water hammer and ball murmur, and means of preventing these issues in cistern pipework were also outlined.

Maintaining the System

Correct choice and placement of valves are crucial for efficient system operation.
Maintaining valves is critical to assuring the correct water levels and flow regulation.

Test Your Knowledge Questions

Series of questions relating to Sure Stop valve function, drain off valve locations, valve pressure requirements, tap types, tap components, mixer tap function, and the meaning of CWCS.

Learning Assessment

A traffic light system for self-assessment, asking the learner for a brief written summary of their understanding in red (I need help), amber (I need clarification), and green (I understand).

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge on cold water storage cisterns with this quiz. It covers important aspects like insulation materials, float operated valves, and installation practices. Perfect for those studying plumbing and water management systems.