Post on 12-Apr-2017
Unit 204Scientific Principles
Understand and carry out site preparation and pipework fabrication
techniques for RAC systems
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Luke Gonzales TMInstR EngTech LCIBSE
Class Rules / Rheolau Dosbarth
Mobile Phones on silent – In Pockets
Appropriate Language
Questions throughout
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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
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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
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*Leak Test is also referred to as tightness testing**Pressure Testing includes both leak & strength testing*
Equipment for Leak & Strength Testing
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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
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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.
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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
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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
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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
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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
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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?
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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
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