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General Restrictions
a. The highest hot or cold water draw off point should not exceed 10m above the Pressure Reducing Valve.
b. An ascending spray type bidet or any other appliance with a Class 1 back-syphonage risk requiring a type A air gap should
not be used.
c. The Gabarrón Mattira combi boiler is only designed to be a self-contained unit powered by electric via the main incoming
terminal block and not by or in conjunction with any other system or source.
d. The Gabarrón Mattira combi boiler should not be used in a situation where maintenance is likely to be neglected.
e. If the supply to the mixer fittings (other than a dual outlet type) is not taken from the balanced supply the system will
become over pressurized and cause the pressure relief valve to discharge. Over time this could also cause the premature
failure of the appliance itself which will not be covered by the warranty.
f. In larger properties with a number of bathrooms/en-suites (not a recommended installation option) and/or long pipe runs,
we would recommend that the balance cold supply is provided with its own pressure reducing valve and is not taken from
the balanced cold connection on the combination valve. In this case, it will also be necessary to fit a small expansion vessel
on the balanced cold water system to accommodate the pressure rise caused by the increase in temperature of the
balanced cold water.
g. Check the performance requirements of the terminal fittings with regard to flow/pressure are suitable.
h. In relation to potable water systems, additional expansion vessels, if required, shall be installed in a vertical orientation and
located so that the length of the connecting pipe work is kept to a minimum.
Shower Fittings
Aerated taps are recommended to prevent splashing. Any type of shower mixing valve can be used as long as both the hot
and cold supplies are mains fed. However, all mains pressure systems are subject to dynamic changes particularly when other
hot and cold taps/showers are opened and closed, which will cause changes in the water temperature at mixed water outlets
such as showers. For this reason and because these are now no more expensive than a manual shower we strongly
recommend the use of thermostatic showers with this appliance. These must be used in 3 storey properties where the
impact on pressure/temperature of opening another tap in the system is greater than normal. The shower head provided
must also be suitable for mains pressure supplies and
not
of high flow rate design in excess of 15 L/min mixed flow rate.
Pipe Layout
In all mains pressure installations it is important to remember that the incoming cold supply must be shared between all
terminal fittings. It is important that a 22mm supply is brought to the appliance. A minimum of one metre of smaller diameter
pipework, or flow restrictors, should be provided on the final connection to all outlets so as to balance the water available. In
any event the distribution pipework should generally be in accordance with BS_EN806-1 to 5.
Plastic Pipework
This appliance is suitable for use with plastic pipework as long as the material is recommended for the purpose by the
manufacturer and is installed fully in accordance with their recommendations.
Note:
Cold supplies to single taps must be taken from the mains cold water system.
Cold supplies to mixer taps must be taken from the balanced cold water connection on the Group combination valve.
Hot Water Outlet
A ½“connection is provided for connection to 15mm pipe. To ensure economic operation the pipe run between the boiler
and taps should be in not more than15 mm dia. pipe and the distance as short as possible. The pipe-work should be insulated
to reduce heat loss.
The installation of the hot water outlet pipe should be in accordance with 4.7 TYPICAL INSTALLATION LAYOUT
