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BEFORE FITTING A COMBI BOILER
THE INSTALLER MUST CHECK:
. What the maximum hot water demand is likely to be placed on the
boiler. Not every installation is suitable for a Combi boiler. Systems
requiring very high hot water flow rates may be better suited with an
unvented cylinder.
2. That the mains are capable of supplying up to 24 litre/min with a
minimum dynamic pressure of .8 bar at the boiler. This is to ensure
that the boiler can achieve its maximum output. To prevent excessive
flow rates ie greater than 24 litre/min it is recommended that a pressure
reducing valve is fitted to the incoming mains water supply, set at 2 bar.
3. Where the mains water pressure is supplied via a borehole pump and
accumulator the pressure variation must not affect the thermostatic
mixer valve. (Contact Warmflow for further details).
4. The hardness of the mains water supply. Systems with hard water must
be fitted with a suitable chemical scale preventer (eg Fernox Quantomat
or Combimate alternatively contact Warmflow for further details).
5. That the flow from any one hot water outlet does not exceed the
maximum recommended. This applies particularly to baths which are
usually fitted with larger taps and larger bore supply pipes. It may be
necessary to restrict the flow to these taps by reducing the bore of the
supply pipework (eg 5mm) or by fitting a restrictor into the pipework.
6. That any outlet when opened does not starve all the other outlets of hot
water. If more than one outlet is open at the same time then the total
flow from all the outlets should not exceed the maximum flow rate of
the boiler.
7. That any showers being supplied with hot water by the boiler are
compatible with this type of appliance (contact Warmflow for further
details).
It should be noted that the boiler has been factory fitted with an
8 litre/min flow restrictor.
The manufacturers guarantees are void if the appliance is not installed
and commissioned in accordance with the recommendations made
herein.
