Bailey Unicorn - Central Heating; Circulation Pump; Bleeding Air

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HEATINGSYSTEMS
objectsintothesystem.
Alde recommends using the Alde 1900-811
or 839 twin-motor service pump to ll the
system.
To ll the system by hand, unscrew the
expansion tank cap (Fig.2 [R]), and lift the
circulationpump(Fig.2[S])outofthetank(if
applicable). Carefully pour the HTF into the
tank,andrepeatuntiltheuidlevelisabout1
cmabovetheMINmarkwhencold.
Fig.2
Central Heating
Theboilerissettoanupperlimittemperature
of 85°C, i.e., the temperature of the heat
transferuid(HTF)asitcirculatesaroundthe
pipes,radiators,convectors,etc.
Toensurethebestperformancefromhydronic
heating, air must be able to circulate freely
around the back of the furniture (Fig.3). Air
vents, cut into the top and bottom of the
furniture, must be unobstructed by carpets,
cushions,orstowage,etc.
The full length of a convector should be
ventilatedforbestperformance.
i
Usegasandelectricheating
simultaneouslyforthebest
performance.Theboilerwillonlyuse
asmuchenergyasisneeded,andis93%
efcientonaSEDBUK(seasonalefciencyof
domesticboilersintheUK)basedtest.
Fig3
Circulation Pump
A pump is used to circulate the HTF around
the central heating system. There are three
modelsofAldecirculationpump.
•12v expansion tank circulation pump.
This light duty pump is ideally suited for
holiday-makers,orasanoff-gridoptionfor
the230vinlinecirculationpump.
•12v inline circulation pump. This heavy
duty, variablespeed pumpisdesignedfor
allyearroundmotorcamping.
•230v inline circulation pump. This heavy
duty pump is powered directly by mains
electric,suitablefornon-touringvehicles.
Bleeding Air
The HTF will contain some air. This is
unavoidable. Air bubbles can also be
introducedwhenthesystemislled.
In a newly lled central heating system, you
will need to bleed air from the bleed points