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Fox & Co install all makes of showers from a simple installation of
an electric unit to the complete erection of a tiled shower enclosure with
lighting and steam extraction facilities. All shower repairs are also
undertaken by Fox & Co
See also Shower Types
Click below for further information
Before
choosing a shower, it is important that you understand the way the hot water is
already heated in your house. Some showers cannot be used with some heating
systems. Our project on
domestic hot water
will help you identify your system. Once you have done that, you can choose your
shower.
ELECTRIC SHOWERS:
Electric showers can be used within
any domestic water system. They, in most cases, are connected to the mains cold
water and an element within the shower heats the water as it passes through the
unit. If you can arrange a clearance of 10 metres from your shower spray to the
underside of the cold water tank, you can fit an electric shower to this. In
this situation the shower must have an independent cold supply from the tank.
The water at your
mains entry must have a running pressure of min 1 bar, must flow at a rate of 8
liters per minute and have a maximum static pressure of 10 bar. Most electric
showers will be configured for these water bye law stipulations but it is as
well to check with the manufactures instructions.
Your shower
must be connected to the mains via a 15mm water pipe and it is just as well to
install an isolation valve in this run. The valve can be turned off if and when
maintenance is required to the shower and this removes the need for water to be
turned off at the mains, disrupting all other water uses. A description and
installation of isolating valves can be found in our
bathroom project
page.
The electrical
connections to an electric shower are covered by many regulations. An electric
shower must be installed on its own circuit and not spurred from any other
connections or appliance. First you must check that your fuse board is capable
of providing the current necessary and must be rated above 60 amps. An RCD
(residual current device) must be installed as, either part of your existing
fuse board, or separately, interrupting the circuit to the shower. Connection to
the fuse board should be by means of a MCB (miniature circuit breaker). Fuse,
switch and cable ratings are also vital and we would suggest that 10mm cable is
used for all installations. This makes upgrading your shower much easier in the
future.
Showers up to 7kw
may carry a 6mm cable as long as the shower unit is within 18 metres of the
fuseboard. Fuses and switches should be rated at 32 amps.
Showers up to
8.5kw may carry a 6mm cable as long as the shower unit is within 18 meters of
the fuse board. Fuses and switches should be rated at 40 amps.
Showers up to
9.5kw carry a 10mm cable to units within 35 metres of the fuse board. Fuses and
switches should be rated at 45amp
Showers up to
12.5kw should carry a 10mm cable to units within 35 metres of the fuse board.
Fuses and switches should be rated at 50 amps.
In all cases the
circuit should be interrupted by a double pole pull cord switch with a neon
on/off indicator and a mechanical indicator should the neon fail.
It is essential,
in all cases, that the shower supply pipes are independently cross bonded to
earth.
MIXER SHOWERS:
Mixer showers are so called because
they will mix the existing hot and cold water, in a special valve, before it is
available at the shower head. They are suitable for either low or high pressure
(check with your supplier that the mixer valve you buy is suitable for the
system you have). They are available as surface mounted fixtures, where the
pipe work is easily installed on the top of your existing surface, or flush
mounted, where the valve is seen, but the pipe work is hidden behind the surface.
They are then ideal to install in a new shower cubicle construction where the
pipes can be built into a wall.
To operate
correctly both the hot and the cold water need to come from a source operating
at the same pressure. Both can come from a mains fed system, (combi boiler or
multi point water heater and cold mains) or both can come from tank fed water
(immersion and cold storage tank). If one supply must come from high pressure
and one from low pressure, a pressure balanced mixer valve can be
installed.
A mixer shower
will not increase the flow of water to your system. If your water flows from
your taps at a poor rate, this is the rate it will feed the shower.
A drawback to
installing a mixer shower is the fact that it will usually be connected to pipes
which supply water to other points. When the other points are used (taps, toilet
cistern etc) the flow rate to the shower will be affected. This in turn will
affect the temperature of the water coming out of the shower and, in the case of
the cold being drawn off elsewhere, could lead to scalding. This can be
overcome, with a low pressure system, by laying separate pipes to the valve from
both hot and cold supplies and making the shower water independent. You may need
to contact a plumber for this as it will mean installing a special flange in the
top of your hot water cylinder. In the case of a mains fed mixer a thermostatic
valve is recommended. Mixer showers cannot be pumped from a mains pressure
system (combination boilers, multi point heaters) but they can from low pressure
systems. There are mixer shower valves especially designed for combination
boilers, (pressure balanced mixer shower) please see your local plumbing
retailer for details.
THERMOSTATIC MIXER SHOWERS:
A thermostatic mixer shower
incorporates a pre-set thermostat that will sense a dramatic change in
temperature and rectify the situation. Some advanced thermostatic mixers will
even cut the water off when a failure in flow is detected. Most thermostatic
mixers also a have a temperature limiting device to stop very high temperatures
being selected by the user.
POWER SHOWERS:
Power showers are mixer showers with
integral pumps which increase the rate of flow from the shower head. They can
only be installed on low pressure, tank fed systems. The cold water tank should
be no less than 50 gallons if supplies many outlets, a 25 gallon cold tank is
acceptable for the shower alone. A dedicated hot and cold supply is necessary.
The water supply must always be above the unit to ensure that the pump is always
primed and does not have to suck any air.
SHOWER PUMPS:
There are two types of shower pump.
The first is a single impeller pump, with one driving blade which pumps the
water, as it is mixed, to the shower head. This means of course it must go
between the mixer valve and the head. The easiest place therefore to install the
single pump is in the loft as it must be above the mixer valve. This can lead to
problems with the cold temperatures in the loft freezing the water and it cannot
be insulated because it needs a free air flow. For this reason a twin impeller
pump was introduced. This is connected to both the hot and cold water before
they reach the mixer valve and can be sited, ideally, in the airing cupboard.
Most pump manufacturers will specify that the pump must be within 4 metres of
the hot water cylinder and at least 30mm below the cold tank. Pumps, as with
power showers, must have a dedicated water supply that serves no other outlets.
They must also be connected to the hot supply with an anti aeration flange such
as an Essex or Warix...In general a Surrey flange should not be used as it can
restrict flow to the pump inlet. An electrical connection is needed and should
be taken from a switched, fused spur on a ring main outside the bathroom. It
will be rated at 5 amps.
DRAINAGE:
Drainage for the shower water can be
provided by an existing bath or shower tray waste, but must be via a 40mm
diameter waste pipe and discharge into a foul water drain. This pipe, in this
diameter, must travel no further than 3 metres before entering the soil stack or
discharge gulley. It cannot be mixed with the rain (surface) water drainage.
Above the ground floor, to comply with building regulations, a deep trap (75mm)
needs to be installed. Below that a shallow trap of 38mm may be used. This is to
stop the water in the trap being siphoned out by water running quickly through
another section of the waste pipe. This drainage detail applies to all makes of
shower.
Article care of DIY Doctor
www.diydoctor.org.uk
Click here for more information
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