Baxi Potterton 24 Eco HE manual Making The Electrical Connections, Preliminary Electrical Checks

8.0INSTALLATION

8.8Making The Electrical Connections

To connect the mains input cable proceed as follows:-

1.	Slacken the facia panel securing screws and lift the
outercase panel so that its securing tabs are clear of
the facia. Remove the panel.
2.	Completely undo the screws securing the facia
panel and hinge it down (Fig. 29).
3.	Remove the control box cover securing screws.
Disengage the barbs on the control box from the
cover. Remove the cover (Fig. 30).
4.	Slacken the cable clamp on the LH side of the
boiler chassis (Fig. 31). Insert the cable through the
clamp and route it to the terminal block.
5.	Slacken the screws in the terminal block, connect
the input cable, and tighten the screws.
6.	If an external control is to be connected it can be
done at this point. Run the input cable from the

Fig. 30

Control Box Cover

Fig. 29

Fig. 31	Facia Panel
Cable Clamp

external control through the second cable clamp on

the boiler chassis. Refer to the instructions supplied

with the control.

7. To connect external control(s) remove the link

between terminals 1 & 2. The 230V supply at

terminal 1 can be connected to the external

control as shown. The switched output from the

external control must be connected to terminal 2.

(Figs. 32).

NOTE: If the room thermostat being used incorporates an anticipator it MUST be wired as shown in Fig. 32.

	Fuse
Fused supply 3A	Always fit fast
230V ~ 50Hz	blow 2A fuse

Live (brown) br

Neutral (blue) b

Earth (green/yellow) g/y

230V 1 bk

2 bk

Terminal Block

Fig. 32

Frost Thermostat
	L	br
L	N	b
N
External Clock		g/y
	1	bk
	230 V
N	2	bk
	SL
Room Thermostat

IMPORTANT: If an integral timer is fitted to the boiler an external frost thermostat wired as shown will not operate correctly. Only external timers may be used in such installations, as in the diagram.

IMPORTANT: The external control MUST be suitable for 230V switching.

Functional Flow Diagram

8.Ensure that both mains input and, where fitted,

external control input cables have sufficient slack to allow the control box to drop down. Tighten the cable clamp(s) on the boiler chassis.

9.If an optional integral timer is to be used it should be fitted at this point. Refer to the instructions supplied with the timer. NOTE: An external frost thermostat cannot be used with the integral timer.

External Controls

L

230 V

br

b

bk

bk

br

Selector /

Reset Switch

b

r

	br
	br
	b
	b
	r
	r
PCB	bk

	Pump
					N
			b
				Pressure Switch
b
br
		Fan
					N
			b

Flue Thermostat

Safety Overheat Thermostat

NTC Sensor

8.9	Preliminary Electrical Checks		Key to Wiring
			b	- blue
1. Prior to commissioning the boiler preliminary			br - brown
electrical system checks should be carried out.			bk - black
		Fig. 33	r	- red
			g	- green
2. These should be performed using a suitable meter,
			w	- white
and include checks for Ground Continuity,

Resistance to Ground, Short Circuit and Polarity.

bk

b

br

bk

r

r

g

g

Gas Valve Modulator

Spark Electrode

Gas Valve

Condensate Trap

Flame Sensing Electrode

Hydraulic Differential Pressure Switch

DHW Flow Priority Microswitch

Publication No. 5111811 23