Warmhaus EWA 2525C Installation & Service Manual Download

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5.8. FLOW & RETURN TEMPERATURE SENSOR

Replacement

CAUTION

Please follow the steps listed in replacement of components FIRST STAGE
1. Disconnect the sensor lead from the flow or return thermistor unit.
2. Unclip and remove the flow or return thermistor from the pipe work and

withdraw the sensor from the boiler.

3. Re-fit the thermistor to the pipe work and ensure it is securely clipped

and in good contact with the pipe work and located into the locator tab.

4. Re-connect the thermistor lead to the thermistor.
Please follow the step listed in replacement of components FINAL STAGE.

5.9. Main PCB Replacement

CAUTION

Please follow the steps listed in replacement of components – FIRST STAGE
1.  Carefully remove the 8 retaining clips and remove the control box cover.
2.  Remove the 2 screws that secure the PCB.
3.  Gently  spread  the  two  side  retaining  clips  and  lift  the  PCB  upwards

ensuring it clears the four corner locating posts.

4. Unplug all electrical connections from the PCB and make a note of where

each connection is located (wiring diagram can be used in reference for

connection locations)

5. If the EEPROM on the existing PCB is in good working order it maybe

be transferred to the new PCB, however the following checks must be

carried out to ensure they match the default settings in the parameter

list.

6.  Check P15 value on the parameter list
7.  Check P22 value on the parameter list
8.  Check P44 value on the parameter list
9.  Check P46 value on the parameter list
10. If you wish to use the new EEPROM supplied with the new PCB then the

above checks must also be carried out.

11. Re-connect all electrical connections to the PCB ensuring they are

connected correctly.

12. Install the PCB in reverse order as the above instructions 3,2,1.
13. When power is restored to the boiler and a new EEPROM has been used

the boiler LCD will display E62 error code.

14. To clear the error code you must run Auto Calibration.
Please follow the step listed in replacement of components FINAL STAGE.

5.10. 3-Way Inner Kit Replacement - TOP

CAUTION

Please follow the steps listed in replacement of components – FIRST STAGE
1.  Refer to the Draining the Boiler CH circuit section
2.  Remove the diverter valve actuator and place safely within the boiler.
3.  Unscrew the top brass connection nut and withdraw the 3 way valve

inner cartridge upwards and out of the boiler.

4. Ensure the brass manifold is clean.
5. Screw the new 3 way valve inner cartridge into the brass manifold

ensuring the spindle connects and fits into the bottom O-ring, tighten

the cartridge.

6. Re-pressurize the boiler and bleed all excess air.
7. Re-connect the diverter valve actuator.
Please follow the step listed in replacement of components FINAL STAGE.

5.11. Pump Head Replacement

CAUTION

Please follow the steps listed in replacement of components – FIRST STAGE
1.  Refer to the Draining the Boiler CH circuit section.
2.  Disconnect the electrical connector plugs from the pump.
3.  Remove the 4 x screws securing the pump head.
4.  Remove the pump head and ensure the pump head housing is clean.
5.  Install  the  new  pump  head  and  secure  the  4  x  pump  head  securing

screws.

6. Reconnect the electrical connector plugs to the pump.
7. Re-pressurize the boiler and bleed all excess air.
Please follow the step listed in replacement of components FINAL STAGE.

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