IDEAL he15, Installation And Servicing

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11 mexico HE -
Installation & Servicing
General
Non-return
valve
Automatic
air vent
Hose unions
Additional
stop valve
Hosepipe
(disconnect
after filling)
Double check valve
assembly
( note direction of flow)
Temporary hose
(disconnect
after filling)
cla7650
Hose
connector
Note.
The pump manufacturers’ minimum requirements must be complied with.
5 LOW hEAD AND LARgE sysTEMs WITh ExTENsIVE pIpE RUNs - OpEN VENT
All dimensions in mm (in.).
NB. Imperial dimensions are approximate
Flow Return
cla7649
6 sEALED sysTEM REqUIREMENTs
This arrangement is useful for large systems where
radiators at the extremities are difficult to vent. This can
lead to pumping over with conventional feed and vent
arrangements.
The following conditions MUST be observed:
1. The top of the automatic air vent must be below the
cold water level.
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 22mm cold feed
pipe should be used in order to reduce the effective
volume of hot system water expanding into the feed/
expansion cistern to a minimum.
a. A non-adjustable preset lift pressure not exceeding 3bar
(45lb/in
2
).
b. A manual testing device.
c. Provision for connection of a discharge pipe.
The valve or discharge pipe should be positioned so
that the discharge of water or steam cannot create
a hazard to the occupants of the premises or cause
damage to electrical components and wiring.
3. pressure gauge
A pressure gauge covering at least the range 0-4 bar
(0-60 lb/in
2
) must be fitted to the system. The gauge
should be easily seen from the filling point and should
preferably be connected at the same point as the
expansion vessel.
Notes.
a. The method of filling, refilling, topping up or flushing
sealed primary hot water circuit from the mains
via a temporary hose connection is only allowed
if acceptable to the local water
authority.
b. When installing the filling device,
it must be connected as shown
to fully comply with the water
regulations. This may involve
the fitting of an additional WRAS
approval isolator valve to the mains
supply.
1. general
a. The installation must comply with the
requirements of BS. 6798 and BS. 5449.
b. The installation should be designed to work with
flow temperatures of up to 82
o
C.
c. All components of the system, including the heat
exchanger of the indirect cylinder, must be suitable
for a working pressure of 3 bar (45lb/in
2
) and
temperature of 110
o
C. Care should be taken in
making all connections so that the risk of leakage
is minimised.
2. safety Valve
A spring loaded safety valve complying with the
relevant requirements of BS. 6759 must be fitted in the
flow pipe as close to the boiler as possible and with no
intervening valve or restriction. The valve should have
the following features: