Open Vented System Requirements; Sealed System Requirements - Keston HEAT 2 45 Installation & Servicing

1.14 OPEN VENTED SYSTEM REQUIREMENTS

Detail reference should be made to the appropriate standards
listed on page 8.
The information and guidance given below is not intended
to override any requirements of the above publications or the
requirements of the local authority, gas or water undertakings.
The vertical distance between the pump and feed/expansion
cistern MUST comply with the pump manufacturer's 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 Keston Heating. The
isolation valves should be fitted as close to the pump as possible.
The boiler is fitted with an automatic air vent, located in the left
top side of the interior. This air vent must never be shut off, as
this could result in dry firing of the boiler and subsequent damage
to the heat exchanger.

1.15 SEALED SYSTEM REQUIREMENTS

Note. The method of filling, refilling, topping up or flushing sealed primary hot water circuit from the mains for a non-domestic
property is shown below.
1. General
a. Detail reference should be made to the appropriate
standards listed on page 8. The information and guidance
given below is not intended to override any requirements of
these publications or the requirements of the local authority,
gas or water undertakings.
b. The installation should be capable of working with flow
temperatures of up to 90
up to 35 o C at minimum rate only.
c. All components of the system, including the heat exchanger
of the indirect cylinder, must be suitable for a working
pressure of 6 bar (87lbf/in
should be taken in making all connections so that the risk of
leakage is minimised.
d. The boiler is fitted with an automatic air vent, located in
the left top side of the interior. This air vent must never be
shut off, as this could result in dry firing of the boiler and
subsequent damage to the heat exchanger.
e. Suitable isolation valves and drain points
must be provided by the installer.
2. Safety Valve
A spring loaded safety valve complying with
the relevant requirements of BS. 6759 Pt. 1
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:
a. A non-adjustable preset lift pressure not
exceeding 6 bar (87lbf/in
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 is visible, but will not cause
hazard to user or plant.
Installation & Servicing
SECTION 1 - GENERAL
o C and a temperature differential of
2 ) and temperature of 110 o C. Care
2
).
CV = Control Valve
DT = Drain Tap
Feed/expansion
cistern
Water
level
(cold)
Open vent
System
return
Connections
to boiler
3. Pressure Gauge
A pressure gauge covering at least the range 0-6 bar 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.
IMPORTANT NOTE: If the boilers are installed on to an Ideal
frame & header kit and operated in excess of 3 bar then all
safety relief valves will require upgrading. The boiler has a
maximum operating pressure of 6 bar.
4. Expansion Vessel
Expansion vessels used must comply with BS. EN 13831.
Connection to the system must not incorporate an isolating
valve.
primary flow
and return
Type BA backflow
prevention device
(RPZ valve assembly)
CV
Air
gap
DT
500mm
minimum
3000mm
Cold
minimum
Feed
System
flow to
pump
Inverted cold
feed entry
ima5351
Strainer
CV
Resillient
seat control
valves
Tundish
Supply
pipe
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