unit 228 powerpoint

Unit 204Scientific Principles

Understand and carry out site preparation and pipework fabrication

techniques for RAC systems

www.cardiffandvalecollege.ac.uk

Luke Gonzales TMInstR EngTech LCIBSE

Class Rules / Rheolau Dosbarth

Mobile Phones on silent – In Pockets

Appropriate Language

Questions throughout


Lesson Objectives / Amcanion Gwersi

Identify appropriate equipment for applying leak & strength tests to

RAC Pipework

State the procedure for completing a leak & strength test to RAC

pipework according to industry standards

Please note throughout the duration you will be

required to complete the worksheet


Why do we Leak & Strength Test?

The purpose of a pressure test is to ensure that the pipe work and system components can withstand

the pressures that they are likely to be subjected to once a system is charged with refrigerant.

• A strength test should comply with EU Standard EN378:2008

– Due to be revised September 2016


*Leak Test is also referred to as tightness testing**Pressure Testing includes both leak & strength testing*

Equipment for Leak & Strength Testing


Equipment

Oxygen Free Nitrogen

Oxygen Free Nitrogen Pressure Testing Regulator

Pressure Test Manifold & Metal Braided Hoses

NOT – Normal Refrigerant Lines or A Manifold with a Sight glass – Why?• Leak Spray


Offer

Leak & Strength Test ProcedureSystems need to be divided into high & low sides for pressure testing – Heat Pump?

This is required for manufactures test pressures to be applied – Shell & Tube Evaps / Condensers

Be mindful of system components – PRV, Pressure Switches, TEVs, Solenoid Valves.


Leak Test Calculation

Whilst carrying out a pressure test within the UK we use the Maximum Allowable Pressure outlined within EN378;• 32⁰C For The Low Side • 43 ⁰C For The High Side –

Water Cooled• 55 ⁰C For The High Side – Air

Cooled

Please Complete Example Activity 4 -

Worksheet


Strength Test CalculationCyfrifiad Prawf Cryfder

The Strength test pressure should be between 1.1 and 1.43 times the maximum allowable pressure of the system.Example:R410A system Air Cooled High side Pressure test55⁰C = …… Bar Gauge

….. x 1.43 = 47.44 Bar Gauge47.44 Bar is your Strength Test Pressure


Task 1 – WorksheetTaflen Waith

You have a total of 10 Minutes to complete the worksheet.*Key Points*

• 32⁰C For The Low Side • 43⁰C For The High Side – Water Cooled• 55⁰C For The High Side – Air Cooled• Use 1.43 to work out your Strength Test

Ask if you require any assistance


Worksheet Feedback

• Task 1: EN 378• Task 3: Manifold with sight glass & normal

gauge lines• Task 4: 33.18 Bar Gauge• Task 5: 47.44 Bar Gauge• Task 6: 9.99 Bar Gauge • Task 7: 14.28 Bar Gauge• Task 8: 23.73 Bar Gauge• Task 9: 33.93 Bar Gauge

Please swap your worksheet with your partner


Recap of Objectives

Have we achieved the following objectives?• Identify appropriate

equipment for applying leak & strength tests to RAC Pipework

• State the procedure for completing a leak & strength test to RAC pipework according to industry standards

Any questions?


Cwestiynau?

Please could you fill out the feedback form I have provided, Thank you.

Apps to DownloadAvailable for IOS & Android

Danfoss - Refrigerant Slider Bitzer – PT Reference


unit 228 powerpoint

Documents