Vaillant ecoTEC plus VU 446/5-5 (H-GB) Installation And Maintenance Instructions Manual page 50

Condition: Gas valve assembly
–
Carry out a leak-tightness check, check the CO2 con-
tent and adjust this, if required.
Condition: Venturi
–
Check the CO₂ content and adjust this, if required.
Condition: Fan
–
Check the CO₂ content and adjust this, if required.
13.9.5 Replacing the heat exchanger
1. Remove the adapter for the flue system.
2. Remove the compact thermal module. (→ Page 44)
5
6
1
4
3. Remove the clips (1).
4. Loosen the flow (2) and return pipe (3).
5. Remove the condensate discharge hose (4) from the
heat exchanger.
6. Remove the rainwater drain hose (6) from the heat
exchanger.
7. Remove the plug (5).
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2
3
4
2
1
8. Remove the screws (1) and (3).
9. Remove the retainer for the heat exchanger (2) and
(4).
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.
Caution.
Risk of poisoning due to escaping flue
gas.
Mineral-oil-based greases can damage the
seals.
▶
Instead of grease, use only water or com-
mercially available soft soap to aid install-
ation.
12. Replace the seals.
13. Insert the flow and return pipes into the heat exchanger
as far as they will go.
14. Ensure that the clips on the flow and return connection
have been attached correctly.
15. Install the compact thermal module. (→ Page 45)
16. Fill and purge the product and, if necessary, the heat-
ing installation.
Installation and maintenance instructions ecoTEC plus 0020261389_03
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