Vaillant ecoTEC plus VUI Series User Manual

56 Installation and maintenance instructions 0020308121_04
10. Insert the new heat exchanger into the grooves on the
back panel.
11. Screw in a new screw tightly on the underside of the
heat exchanger.
12. If you have removed an existing front retainer, use two
screws each to screw the retainer in tightly.
13. Secure the condensate discharge hose on the heat
exchanger.
14. Insert the flow/return pipes into the heat exchanger as
far as they will go. When doing so, replace all of the
seals.
15. Secure the clips to the flow/return pipe.
16. Install the compact thermal module. (→ Section 12.7.2)
17. Install the side casing. (→ Section 13.7.20)
18. Install the connector for the air/flue pipe.
(→ Section 7.2.6.2)
19. Fill the heating installation. (→ Section 9.9)
20. Purge the heating installation. (→ Section 9.10)
13.7.9 Replacing the expansion vessel
1
4
2
3
1. Undo the nut (3).
2. Undo the screw (1) on the support plate (4) and re-
move the support plate.
3. Pull out the expansion vessel (2) to the side.
4. Insert the new expansion vessel into the product.
5. Screw in the nuts below the expansion vessel tightly.
Use a new seal for this.
6. Use the screw to secure the support plate.
7. Fill the heating installation. (→ Section 9.9)
8. Purge the heating installation. (→ Section 9.10)
13.7.10 Replacing the expansion vessel on the shift-
load cylinder
1. Close the cold-water isolation valve.
2. Open a hot water tap to depressurise the water circuit.
Close the hot water tap.
3
2
1
3. Unscrew the screw (1) from the cover (2) of the shift-
load cylinder.
4. Remove the cover.
5. Undo the nut (3) on the expansion vessel.
6. Detach the expansion vessel from the screwed pipe
and remove it from the EPS insulation.
7. Insert the new expansion vessel into the EPS insula-
tion.
8. Connect the new expansion vessel. Use a new seal for
this.
9. Check the filling pressure of the expansion vessel
(minimum pressure is 0.4 MPa (4 bar)).
10. Fill and purge the heat generator and the shift-load
cylinder.
13.7.11 Replacing the cylinder charging pump on
the shift-load cylinder
1. Close the domestic hot water system isolation valves
and drain the heat generator and shift-load cylinder on
the domestic hot water side.
1
6
5
4
2
3
2. Remove the drain pipe (1) from the expansion relief
valve on the heat generator.
3. Hinge the heat generator's electronics box forward.
4. Open the electronics box.

Vaillant ecoTEC plus VUI Series Specifications

General

Brand	Vaillant
Model	ecoTEC plus VUI Series
Category	Boiler
Language	English