Page 151 - The City and Guilds Textbook: Plumbing Book 1 for the Level 3 Apprenticeship (9189), Level 2 Technical Certificate (8202) and Level 2 Diploma (6035)

Chapter 2 Common processes and techniques

Correctly used, these techniques will help to contain fire in the room where it
started, reducing damage.

Testing and commissioning procedures

Testing of installations is the first time we see whether the installation is
watertight. For pressure systems and sanitary systems, testing procedures are
set out in the relevant British Standards and Regulations.

Pre-testing checks
Before commissioning takes place:

● walk around the installation; check that you are happy that the installation is
correct and meets installations standards
● check that all open ends are capped off and all valves isolated
● check that all capillary joints are soldered and that all compression joints are
fully tightened
● check that sufficient pipe clips, supports and brackets are installed, and that
all pipework is secure.
INDUSTRY TIP
Testing procedures
You can access the Building
Testing procedures differ depending on the type of pipework installed. The Regulations 2010 Approved
process involves filling the system with water to a specific pressure, letting Document H: Drainage and
it stand for a period of time to temperature stabilise and then checking it for waste disposal at: www.gov.
pressure loss. Here, we will look at those different testing procedures. uk/government/uploads/
system/uploads/attachment_
Hot and cold water systems testing is detailed in BS 6700; central heating data/file/442889/BR_PDF_
systems testing is detailed in BS 5449; above-ground sanitation systems should AD_H_2015.pdf
be tested in accordance with Document H of the Building Regulations.
● Copper tubes and low carbon steel pipes: systems installed in copper
tube and low carbon steel pipes should be tested to 1.5 times normal
operating pressure. They should be left for a period of 30 minutes to allow
for temperature stabilisation and then left for a period of one hour with no
visible pressure loss.
● Plastic (polybutylene) pressure pipe systems: these are tested rather
differently to rigid pipes. There are two tests that can be carried out. These
are known as test type A and test type B and are detailed in BS 6700:
● Test type A: slowly fill the system with water and raise the pressure to
1 bar (100 kPa). Check and re-pump the pressure to 1 bar if the pressure
drops during this period, provided there are no leaks. Check for leaks.
After 45 minutes, increase the pressure to 1.5 times normal operating
pressure and let the system stand for 15 minutes. Now release the
pressure in the system to one-third of the previous pressure and let it
stand for a further 45 minutes. The test is successful if there are no leaks.

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