4 heating system – Glow-worm EnergySaverCombi 100 User Manual
Page 11
![background image](/manuals/736767/11/background.png)
11
221854B
4.1 General
The boiler is for use only with sealed central heating systems.
The safety valve is an integral part of the boiler and it cannot be
adjusted.
A pressure gauge is incorporated on the boiler control panel to
indicate the system pressure.
The circulation pump is integral with the boiler. The Combi 2-
80 is fitted with a UPS 25-50 pump and the Combi 2-100 is fitted
with a UPS 25-60 pump. Performance curves for both pumps
are shown in diagram 4.1.
4.2 Expansion Vessel
The boiler has an integral expansion vessel with a capacity of
7 litres (1.54 gallons), with a charge pressure of 0.5bar.
The maximum heating system water content using the fitted
expansion vessel is 130 litres at an average temperature of
75
O
C, and charge pressure of 1.0bar.
4.3 Flow Rate
The minimum flow rate through the boiler is 1053 litres/hr for
ES80 and 1230 litres/hr for ES100. This is equal to 20
O
C
differential at maximum heat input.
The system can be fitted with a lockable balancing valve if
necessary in the main flow or return pipes shown as valve "A"
in diagram 4.2.
Diagram 4.1
9078
4.4 Bypass
The boiler is fitted with a manual bypass, see diagram 4.3. This
valve may be adjusted by the installer if necessary to ensure at
least 1053 litres/hr for ES80 and 1230 litres/hr for ES100 flow
through the boiler. The boiler is supplied with the bypass open
by approximately half a turn and is closed by turning the white
screw clockwise. However for systems completely fitted with
thermostatic radiator valves or systems of high pressure loss an
additional bypass valve must be fitted to the heating circuit to
ensure that under no circumstances does the flow rate drop
below this level.
An additional bypass valve “B” is shown in diagram 4.2.
4.5 Filling Sealed Systems
Provision for filling the system at a low level must be made. Two
methods of filling are shown in diagram 4.4. There must be no
permanent connection to the mains water supply, even through
a non-return valve.
4 Heating System