8
Classic
FF
-
Installation & Servicing
GENERAL
Minimum Requirements
Note.
The pump manufacturers minimum
requirements must be complied with.
System
return
Connections
to boiler
Inverted cold
feed entry
System
flow to
pump
150 (6")
Max
15mm
Cold
feed
450 (18")
Mimimum
450 (18")
Mimimum
22mm
Open vent
Feed / expansion
cistern
Water
level
(cold)
Surge
arrester
75 (3)
Min.
450
(18)
Min.
200
(8)
Min.
Highest
point of
flow or
return
150
(6)
Max
Max. practical
length
To pump
Cold
water
level
Feed / expansion
cistern
75 (3) Min.
Flow
Return
22 (3/4)
Open vent
All dimensions in mm (in.). N.B.
Imperial dimensions are approximate
4
LOW HEAD INSTALLATIONS
The system should be vented directly off the boiler flow pipe, as
close to the boiler as possible. The cold feed entry should be
inverted and MUST be positioned between the pump and the vent,
and not more than 150mm (6") away from the vent connection.
There should be a minimum height - 450mm (18") - of open vent
above cistern water level. If this is impossible refer below.
The vertical distance between the highest point of the system and
the feed/expansion cistern water level MUST not be less than
450mm (18").
The pump MUST be fitted on the flow side of the boiler.
A suitable pump is a domestic circulator capable of providing an
11°C (20°F) temperature differential (e.g. Grundfos UPS 15/50 or
equivalent). The vertical distance between the pump and feed/
expansion cistern MUST comply with the pump manufacturers
minimum requirements to avoid cavitation. Should these
conditions not apply, either lower the pump position or raise the
cistern above the minimum requirement specified by Caradon
Ideal Limited.
Note.
A cold water feed must be available back to the boiler, when
all automatic valves are in the closed position (refer to BS. 6798)
and when close coupled the feed must not be in a vertical leg.
The Classic range of boilers can be installed in
low head situations by fitting a 'surge arrester' in
the expansion pipe as shown.
The following conditions MUST be observed:
1. The surge arrester must be at least 42mm in
diameter x 150mm long, thus ensuring a
MINIMUM air gap and a MINIMUM depth of
water below the static water level (cold) of
75mm.
2. The static water level (cold) must be at least
200mm above the top of the horizontal flow
pipe, fitted as shown. The vent connection
MUST NOT be made immediately off the top of
the boiler, as venting is made less efficient.
3. The maximum practical length of 15mm cold
feed pipe should be used in order to reduce
the effective volume of system water
expanding into the feed/expansion cistern to a
minimum.
3
OPEN VENT SYSTEM REQUIREMENTS - FULLY PUMPED
ELECTRICAL SUPPLY
WARNING. The appliance MUST be efficiently earthed.
Wiring external to the appliance MUST be in accordance with the
current I.E.E. (BS.7671) Wiring Regulations and any local
regulations which apply. For Ireland reference should be made
to the current ETCI rules for electrical installations.
The point of connection to the mains should be readily accessible
and adjacent to the boiler, except that for bathroom installations;
the point of connection to the mains MUST be situated outside of
the bathroom.
Note.
Where a room sealed appliance is installed in a room containing a
bath or shower then the appliance and any electrical switch or
appliance control utilising mains electricity should be so situated
that it cannot be touched by a person using the bath or shower.
See Frame 38 for details.
