Baxi Potterton Gold HE A Range manual Appliance Operation, Frost Protection Mode, Pump Protection

Central Heating Circuit

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	3.0	Appliance Operation
3.1		Central Heating Mode (Fig. 2)
1. With a demand for heating, the pump circulates water
through the primary circuit.
2. Once main burner ignites the fan speed controls the gas
rate to maintain the heating temperature measured by the

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temperature sensor.

3. When the flow temperature exceeds the setting

temperature, a 3 minute delay occurs before the burner

relights automatically (anti-cycling). The pump continues to

run during this period.

4. When the demand is satisfied the burner is extinguished

and the pump continues to run for a period of 3 minutes

(Pump Overrun).

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3.2 Domestic Hot Water Mode (Fig. 3)

1. Priority is given to the domestic hot water supply. A

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	Fig. 2
Key
1	Primary Heat Exchanger			15 Domestic Hot Water Outlet
2	Burner
				16	Heating Flow
3	Ignition Electrodes
				17	Pressure Gauge
4	Flame Sensing Electrode
				18	Water Pressure Sensor
5	Gas Valve
				19 Automatic By-Pass
6	Pump
				20	Fan
7	Automatic Air Vent
				21	Diverter Valve Assembly
8	Plate Heat Exchanger
				22	Diverter Valve Motor
9	Flow Sensor with Filter & Regulator
				23 Domestic Hot Water Flow Temperature Sensor
10	Pressure Relief Valve
				24	Safety Thermostat
11	Boiler Drain Point
				25 Central Heating Temperature Sensor
12	Heating Return
				26	Expansion Vessel
13 Cold Water Inlet On/Off Valve and Filter
				27 Heat Exchanger Air Vent
14	Gas Inlet

demand at a tap or shower will override any central heating

requirement.

2. The flow of water will operate the Hall Effect Sensor

which requests the 3 way valve to change position. This will

allow the pump to circulate the primary water through the

DHW plate heat exchanger.

3. The burner will light automatically and the temperature of

the domestic hot water is controlled by the temperature

sensor.

4. When the domestic hot water demand ceases the burner

will extinguish and the diverter valve will remain in the

domestic hot water mode, unless there is a demand for

central heating.

Domestic Hot Water Circuit

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IMPORTANT: When the selector switch is in the ‘0’ (Off) position the electrical supply to the boiler is isolated. The boiler will not operate and the integral timer will require resetting once the selector switch is set to either Position (i) or Position (ii).

3.3	Frost Protection Mode
1. The frost protection mode is integral to the appliance and
functions only with the selector switch (see Section 2.1) in
the domestic hot water and central heating position. If the

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system temperature falls below 5° C then the boiler will fire
on its minimum setting until a flow temperature of 30° C is
reached.
3.4	Pump Protection

1.With the selector switch (see Section 2.1) in either the central heating or central heating and domestic hot water position, the pump will automatically operate for 1 minute in every 24 hours to prevent sticking.

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Fig. 3

© Baxi Heating UK Ltd 2008 9