Descaling The Heat Exchanger; Checking The Burner; Cleaning The Condensate Duct - Vaillant ecoTEC plus VU GB 656/4-5 A Installation And Maintenance Instructions Manual

2. Use vinegar (max. 5% acid) to clean the heating coils
(2) on the heat exchanger (1).
3. After a reaction time of 20 minutes, use a sharp jet of
water or a plastic brush to rinse the loosened dirt. Do
not point the water jet directly at the burner insulation
on the back of the heat exchanger.
◁
The water flows out of the heat exchanger through
the condensate trap.
8.5

Descaling the heat exchanger

1. Drain the product. (→ Page 28)
2. Remove the automatic air vent from the air separator.
3. Fill the product with descaler (ET 990098) via the open
connection on the automatic air vent.
4. Fill the product with clean water up to the nominal pres-
sure.
5. Set the pump to "Continuous".
6. Use the chimney sweep button to heat up the product.
7. Leave the descaler to work in maximum output opera-
tion for approx. 30 minutes.
8. Then thoroughly rinse out the product with clean water.
9. Set the pump back to its starting condition.
10. Open the service valves and, if required, fill the heating
installation.
0020214491_01 ecoTEC plus Installation and maintenance instructions
Inspection and maintenance 8
8.6

Checking the burner

1
2
1. Check the surface of the burner for damage. If you see
any damage, replace the burner.
2. Replace the silicone seal (1) and the silicate cord (2).
3. Check the burner insulation (3) on the burner flange
and, if required, replace the burner insulation.
8.7

Cleaning the condensate duct

1
2
1. Observe the installation manual for the condensate
trap's cartridge.
2. Remove the condensate trap's cartridge from below the
product.
3. Pull out the clamp from below the heat exchanger.
4. Remove the elbow connector.
5. Remove the condensate trap (2) and the corrugated
pipe (1). In doing so, note the position of the latching
lugs.
6. Clean the condensate trap, the corrugated pipe and the
condensate trap's cartridge.
7. Fill the condensate trap's cartridge with water.
8. Install the components with new seals and six new, self-
locking nuts.
1 2
1
2
3
27