Vaillant ecoTEC pro 24 Installation And Maintenance Instructions Manual

Also see for ecoTEC pro 24: Instructions for use Instructions for installation and servicing Instructions for installation and servicing Instructions for installation and servicing

9 Troubleshooting26 Installation and maintenance instructions ecoTEC pro 0020244995_029.6.2 Replacing the fan or gas valve678314521. Remove the air intake pipe.2. Remove the plug from the gas valve (7).3. Remove the plug from the fan motor (6) by pushing inthe latching lug.4. Unscrew either the cap nut (2) on the gas valve or thecap nut (8) between the gas pipes. Secure the gas pipeagainst twisting.5. Unscrew the three screws (2)-(4) between the mixturepipe (1) and the fan flange.126. Remove the entire fan/gas valve unit from the product.7. If you want to replace the gas valve, unscrew the capnut (2) if the gas pipe is still secured to the gas valve.8. Unscrew both fixing screws (1) on the gas valve andremove the fan from the gas valve.9. Replace the defective fan or the defective gas valve.10. Install the gas valve and the fan in the same position asbefore. Use new seals.11. Screw the fan to the gas valve.12. If you had removed the gas pipe, screw the cap nutof the gas pipe (2) only loosely to the gas valve. Onlytighten the cap nut on the gas valve after the installa-tion work has been completed.13. Refit the entire fan/gas valve unit in reverse order. Youmust use a new seal (5) for this.14. Ensure that the order in which the three screws arescrewed in between the fan and the mixture pipe cor-responds to the numbering (3), (2) and (4).15. Tighten the cap nut (2) on the gas valve and the capnut (8) between the gas pipes. In the process, securethe gas pipe against twisting. Use new seals.16. After you have completed this work, carry out a leak-tightness test (function check). (→ Page 22)17. If you have installed a new gas valve, adjust the gasratio setting. (→ Page 20)9.6.3 Replacing the heat exchanger1. Drain the product. (→ Page 30)2. Remove the compact thermal module. (→ Page 28)3. Detach the condensate drain hose from the heat ex-changer.1234. Remove the clamps (2) and (3) from the flow connec-tion and the return connection.5. Detach the flow connection.6. Detach the return connection.7. Remove two screws (1) on each of the two retainers.128. Remove the lower three screws (2) on the rear sectionof the retainer.9. Swing the retainer to the side around the top screw (1).10. Pull the heat exchanger downwards and to the right,and remove it from the product.11. Install the new heat exchanger in reverse order.12. Replace the seals.