andrews COMBIflo 100/300, Installation, Operation And Maintenance Manual

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ANDREWS COMBIfl o 25 GB
A Secondary Return circuit may be fi tted to the 1” nipple at the top of the appliance . In all cases, for
serviceability, the recirculation pipe must be fi tted with a stop valve immediately before the connection point.
4.9 CONDENSATE DISPOSAL
Condensation is formed in the normal operation of the appliance and this must be continuously discharged into
a drain. Given the acidity level of condense discharge (pH 3.5 - 4.5) only plastic material can be used for the
discharge pipe work.
40mm pipe with a drop of at least 45 mm for every metre of horizontal pipework should be used. Two traps
are supplied on a 100/300 model and three traps on a 150/300 model. These traps should be connected into a
drain via a tundish or air break.
External routed pipework should be avoided, but if not possible any outside pipework should be run in a mini-
mum of 40mm diameter and be insulated to a minimum of 13mm protection against frost and freezing tempera-
tures. Insulation must be waterproof and UV resistant
CAUTION
The condensate traps must be fi lled with water before operating the appliance.
It is important that the condensate fl ow must be maintained, even in freezing conditions. In the
event that the condensate becomes blocked, the appliance will shutdown completely, and will not
operate again until the fl ow has been restored.
4.8 SECONDARY RETURN DESIGN (DHW CIRCULATION PUMP)