Replacing The Electronics On The Shift Load Storage Tank; Replacing The Electronics And The Display On The Combination Boiler - Vaillant ecoTEC plus 937 Instructions And Maintenance Instructions

9 Replacing components
Danger!
d
Before replacing components ensure that the
safety instructions from Section 9.1 are ob-
served.
• Isolate the unit from the mains as described in Sec-
tion 9.1.
• Close the gas isolator valve in the gas supply pipe.
• Close the stop valves in the hot water system and
drain the water out of the combi boiler and the shift
load storage tank.
• Remove the discharge pipe (1) of the heating pressure
relief.
• Separate the electrical wire of the aqua sensor from
the wiring harness by pulling off the plug from the
wiring harness.
• Release the fitting (2) and (3) on the elbows (4)
and (5).
• Turn the Aqua-Sensor slightly to the side and pull the
Aqua-Sensor downwards out of the chassis.
• Remove the pipe elbow from the Aqua-Sensor.
• Fit the pipe elbow onto the new Aqua-Sensor and use
new gaskets.
• Mount the new Aqua-Sensor in reverse order and re-
place the seals.
• Connect the line plug of the Aqua-Sensors with the
wiring harness.
• Re-fit the discharge pipe (1) and use new gaskets.
• Filling and vent the combi boiler and the shift load
storage tank.
• After completion of the work check the system for
water leaks and carry out a function test (see Sec-
tion 7.8).
9.9 Replacing the electronics on the shift load
storage tank
Fig. 9.10 Replacing electronics
d Danger!
Before replacing components ensure that the
safety instructions from Section 9.1 are ob-
served.
56
• Isolate the unit from the mains as described in Sec-
tion 9.1.
• Close the gas isolator valve in the gas supply pipe.
• Comply with the assembly and installation manuals
provided with the spare parts.
• Remove the screw on the top cover of the shift load
storage tank and remove the cover.
• Pull the electronics (1) out of the location slot.
• Pull off the plug connector from the wiring harness.
• Fit the new electronics in reverse order.
• Start up the appliance.
Check the correct setting of the unit variants (DSN) as
follows:
• Enter the 2nd diagnostic level of the combi boiler .
• Set the equipment-specific DSN value (parameter
"d.93") in accordance with Table 10.1.
Appliance type
ecoTEC plus 937
Table 9.1 DSN Setting Values
• Exit the diagnostic mode.
The combi boiler ecoTEC plus 937 is ready for operation.
9.10
d
• Comply with the assembly and installation manuals
provided with the spare parts.
Replacing the display or the electronics
If you are only replacing one of the two components the
1
parameter settings take place automatically. When
switching the unit on the new component automatically
takes the pre-set parameters from the components
which have not been changed.
Replacing the display or the electronics
When replacing both components, after being turned on,
the appliance goes to fault and displays the error mes-
sage F.70.
• In the second diagnostic level, under the diagnostic
point "d.93" enter the number of appliance variant
according to Table 9.1 (see Chapter 9.9).
The electronics is now set to the appliance type and the
parameters of all adjustable diagnostic points corre-
spond to the factory settings.
Installation and maintenance instructions ecoTEC plus 0020031552_03
Replacing the electronics and the display on
the combination boiler
Danger!
Before replacing components ensure that the
safety instructions from Section 9.1 are ob-
served.
DSN
8