Bosch 715ES Quick Start Manual page 2

18 | G3-23 | 715ES, C800ES, C920ES, C920ESC, 2400ES, 2700ES
4. Remove two 8mm nuts from ignition group. (Fig. 3, pos. 1).
5. Remove ignition group and gasket from the water heater. Leave
the observation window in place.
Cleaning ignition group
1. If the ignition group gasket is discolored or torn, replace with a
new gasket. (Fig. 4)
2. Using steel wool, gently polish all metal surfaces of the flame
sensor and the ignition electrodes. (Fig. 4)
Flame
sensor
Data subject to change without notice | Printed in the USA | BTC710002310 A | 01.2009
Figure 3
|
Figure 4
Gasket
Ignition
electrodes
Replacing ignition group
1. Gently place ignition group gasket over left bolt stud for 8mm
nut. The stud will hold the gasket in place.
(Fig. 3, pos. 1)
2. Carefully feed tips of ignition group into heat exchanger ensuring
that the flame sensor rod is on the far left.
3. Ensure a proper seal between the heat exchanger and ignition
group.
4. Replace and tighten two 8mm retaining nuts. (Fig. 3, pos. 1).
5. Reconnect two large ignition wires to the right and center igniter
terminals. (Fig. 2, pos. 2).
6. Reconnect small black flame sensor wire to the left terminal.
(Fig. 2, pos. 3).
7. Ensure that all three wire connections fit securely on the
terminals.
8. Replace combustion cover and front cover. (Fig. 1).
9. Plug in water heater's power cord and press On/Off button to
"ON". Reset any error that is displayed.
10. Open manual gas shutoff valve.
11. Return water heater to service.
!
WARNING
FAILURE TO PROPERLY SEAL THE
IGNITION GROUP WITH GASKET MAY
CREATE A HAZARDOUS CONDITION
CAUSING SEVERE PERSONAL INJURY
OR DEATH.
Service bulletin
Bosch Thermotechnology Corp.
50 Wentworth Avenue
Londonderry, NH 03053
Tel: 1-866-642-3198
Fax: 1-603-584-1681
www.boschhotwater.com
Bosch Thermotechnology Corp.