Page 111 - 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

to 240°C and is suitable for making end feed capillary joints on all domestic
plumbing, heating and gas systems.

The use of leaded solder is permitted for use on gas and central heating installations,
but there is always a risk that this solder will be used on the wrong system and, if
this occurs, the plumber risks a hefty fine and a criminal record if prosecuted.

Fluxes are used to clean oxides from the surface of the copper and to help with
the flow of solder into the fitting. There are two basic forms of flux available:

1 Active fluxes: otherwise known as ‘self-cleaning’ flux because it cleans the
copper tube and the fitting during the soldering process. Cleaning of the
tube and fittings beforehand is not necessary. Some types of active flux
are known to contain hydrochloric acid, which can be harmful if not used
correctly and can promote corrosion in copper tubes if excess flux is not
removed after soldering has been completed. They are, however, potable in
water, which means they dissolve in contact with water and are flushed out
when initial flushing of the system takes place.
2 Traditional flux paste: usually made from zinc chloride and/or zinc ammonium
chlorides. Some fluxes contain other active ingredients such as amines. Cleaning
of the tube and fitting is required with this type of flux and it is not potable. It
will remain in the pipe after the soldering process has been completed and will
not flush out during commissioning, so it should be used sparingly.

Compression fittings to BS EN 1254:1998

Compression-type fittings are mechanical fittings that require tightening with a
spanner to make a watertight joint. There are two different types:

1 type A – non-manipulative compression fittings
2 type B – manipulative compression fittings.

Fitting type A: non-manipulative compression fittings, step by step
This type of fitting consists of three main parts: the fitting body, a metal ‘O’
ring called an olive, and the back nut. It is called ‘non-manipulative’ simply
because neither the tube nor the fitting need working, or ‘manipulating’, to
make the joint. When the nut is tightened, the olive is slightly compressed onto
the copper tube. To make a type A fitting, follow these steps:

STEP 1 Cut and de-burr the tube. STEP 2 Take apart the fitting, and slip STEP 3 Assemble the fitting and tighten
the nut and olive over the tube. by hand. Then, using an adjustable
spanner, turn the nut clockwise 1.5 to 2
turns to fully tighten the joint.
p Figure 2.22 Making a type A fitting

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