Page 350 - The City and Guilds Textbook: Plumbing Book 1 for the Level 3 Apprenticeship (9189), Level 2 Technical Certificate (8202) and Level 2 Diploma (6035)

The City & Guilds Textbook: Plumbing Book 1

● Remove the old tap and clean the hole.
● Take off the locking nut to the new tap and make sure that the rubber grab
washer is in place on the tap.
● Insert the tap into the appliance and wind up the new locking nut clockwise
by hand, then finally tighten with the tap spanner.
● Replace the fibre sealing washer on the tap connector and wind the tap
connector onto the tap. Tighten the tap connector.
● Turn on the water, check for leaks and test the tap.

When replacing old BS 1010 taps, the threaded tap-connecting tail is longer
than more modern taps. This means that a tap extender fitting is used to
lengthen the thread to the correct length for it to fit the existing pipework.
Tap extender fittings are available from most good plumbers’ merchants.

Repairing a BS 1212 Part 1 float-operated valve (Portsmouth type)
Portsmouth-type float-operated valves are allowed to be fitted on new
installations only if some form of backflow prevention device is installed
before the float-operated valve; usually this would be a double check valve.
However, if a Portsmouth valve is part of an existing installation, then repair
is permissible. To repair a Portsmouth valve, follow the steps listed below.

1 Turn off the water supply at the isolation valve to the float-operated valve.
2 Remove the float-operated valve from the cistern by unscrewing the union
nut.
3 Remove the end cap on the valve body.
4 Remove the cotter (split) pin holding the float arm to the valve body and
remove the float arm.
5 Remove the piston from the valve body.
6 The piston is generally made from one of two materials. It can either be brass
or nylon.
7 For brass pistons, the float-operated valve washer is held in the end of the
piston by a retaining cap, which will need to be unscrewed to allow the
washer to be removed. To remove the retaining cap:
● place a flat-blade screwdriver in the slot for the float arm and unscrew
the retaining cap using a pair of pliers
● remove the washer and replace with a like-for-like washer
● replace the retaining cap and tighten
● check the piston for any signs of scale and remove these with a cleaning
pad.
8 For nylon pistons, simply push the washer out of the gap in the side of the
washer housing and replace the washer.
9 Remove the orifice from the float-operated valve body and check to ensure
that there are no cracks or splits visible. Replace as necessary.
10 Reassemble the valve, making sure that the washer is towards the spindle.
11 Replace the cotter pin and open to ensure that it does not fall out.
12 Re-install the valve into the cistern, making sure the fibre sealing washer is
in place.
13 Re-tighten the union and turn on the water.
14 Check the operation of the valve, adjusting the water level as necessary.

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