0 introduction – Baxi Potterton BAXI COMBI INSTANT 105 HE User Manual
Page 5
2.0 Introduction
5
2.1
Introduction
1. Your Baxi Combi Instant 80 HE or 105 HE is a gas
fired, room sealed, powered flue condensing combination
boiler, providing central heating for your home and mains
fed domestic hot water to taps and shower. It is fully
automatic and does not have a pilot light.
2. Priority is given to the hot water mode - when a hot
water tap is turned on the supply of heat to the central
heating circuit is interrupted.
3. Due to the high efficiency and resultant low flue gas
temperature when in condensing mode a white plume of
condensate will be emitted from the terminal. This will be
particularly evident during periods of low outside
temperature.
2.2
Instant Domestic Hot Water
1. The boiler expansion vessel incorporates a small
volume of stored primary hot water.
2. When the boiler has been off and there is then a
demand for domestic hot water the stored primary hot
water ensures that domestic hot water is supplied
instantly at temperature.
3. The stored hot water is part of the primary circuit. This
is not supplied as domestic hot water, which is fresh
mains water heated by a heat exchanger within the boiler.
4. The stored primary hot water temperature is
maintained whilst the boiler is in operation. During a
period when there is no demand for heating or hot water
the temperature of the stored primary hot water will
eventually fall. The boiler will operate occasionally in
order to maintain the temperature. This is indicated by
the domestic hot water mode neon flashing (item 13 of
Fig. 3).
2.3
Facia Panel
1. The facia panel is behind the hinged lower door panel.
As well as the on/off/reset selector switch, central heating
temperature control knob, pre-heat control and pressure
gauge, the facia incorporates ten neon indicator lights.
2. Neons 12 to 15 indicate the operational status of the
boiler. Neons 6 to 11 have a dual function, indicating the
temperature of the central heating water when constantly
illuminated. If a fault develops the appropriate neon will
begin to flash. Refer to Sections 3.3 to 3.7.
30
o
40
o
50
o
60
o
70
o
80
o
2
1
0
4
3
bar
Reset
OFF
ON
PREHEAT
Fig. 3
30
o
40
o
50
o
60
o
70
o
80
o
1.On/Off/Reset Selector Switch
2.Central Heating Temperature Control
3.Pre-Heat Control
4.Central Heating System Pressure Gauge
5.Optional Integral Timer Position
Neon Indicators
6.Flame Failure or Blocked Condensate Drain
7.Safety Thermostat Activated (Boiler or Flue)
8.Fault on Fan or Flue
9.Fault on Pump or Low System Pressure
10.Fault on Hot Water Sensor
11.Fault on Central Heating Sensor
12.Power On
13.Domestic Hot Water Mode
14.Central Heating Mode
15.Burner On
3
2
1
4
5
6
7
8
9
10
11
12
13
14
15
KEY TO FACIA PANEL (Fig. 3)
When neons 6 to 11 are
constantly illuminated, they
indicate the temperature of the
central heating water.
Hinged Lower
Door Panel
Facia Panel