Vaillant ecoTEC plus VU 446/5-5 (H-GB) Installation And Maintenance Instructions Manual page 14

5 Installation
▶
Connect the external pump for the decoupled heating
circuit to the plug X16 for the main PCB.
▶
Connect the pump for the decoupled domestic hot water
circuit to the plug X13 for the main PCB.
▶
Connect the temperature sensor for the low loss header
to plug X41 on the main PCB. Observe the instructions
for the low loss header.
▶
In order to control the cylinder's post-heating, connect
a VR 10 temperature sensor or a thermostat to the plug
that is connected to the main PCB.
Wiring diagram (→ Page 50)
▶
Set diagnostics code D.026 to 2.
Overview of diagnostics codes (Applicability: VU 446/5-
5 (H-GB) OR VU 606/5-5 (H-GB)) (→ Page 42)
5.1.4 Basic system diagram type 4: Cascade
with two boilers plus one cylinder that is
connected to the boiler
1 Wall-hung boiler with
internal pump
2 Prioritising diverter
valve
3 Low loss header or
plate heat exchanger
The product can control a cascade system.
Number for Control
the basic system
diagram
0020259032 VRC 700
system
control
VR 70 multi-
functional
module
The settings for the internal pump are made at the factory.
▶
Ensure that there is sufficient dimensioning for the
connections and the domestic hot water cylinder.
(→ Page 15)
▶
Connect the domestic hot water circulation pump to the
plug X16 on the main PCB.
▶
Connect the external prioritising diverter valve to the plug
X13 on the main PCB.
▶
Connect the temperature sensor for the low loss header
to plug X41 on the main PCB. Observe the instructions
for the low loss header.
14
1 6
2
3
4
5
4 Domestic hot water
cylinder
5 Heating circuits
6 External domestic hot
water circulation pump
Number Carrying out the
of cir- wiring
cuits
2 Inform Customer
Service.
▶
In order to control the cylinder's post-heating, connect
a VR 10 temperature sensor or a thermostat to the plug
that is connected to the main PCB.
Wiring diagram (→ Page 50)
▶
Set diagnostics code D.026 to 1.
Overview of diagnostics codes (Applicability: VU 446/5-
5 (H-GB) OR VU 606/5-5 (H-GB)) (→ Page 42)
5.1.5 Basic system diagram type 5: Cascade
with two to seven boilers + a cylinder that is
connected to the heating circuit
1 Wall-hung boiler with
internal pump
2 Heating circuits
3 Low loss header or
plate heat exchanger
The product can control a cascade system.
Number for Control
the basic system
diagram
0020259033 VRC 700
system
control
VR 71 multi-
functional
module
The settings for the internal pump are made at the factory.
▶
Ensure that there is sufficient dimensioning for the
connections and the domestic hot water cylinder.
(→ Page 15)
▶
Downstream of the low loss header, select a domestic
hot water pump that is suitable for the domestic hot water
cylinder.
▶
Connect the pump for the decoupled domestic hot water
circuit to the plug X13 for the main PCB.
▶
Connect the temperature sensor for the low loss header
to plug X41 on the main PCB. Observe the instructions
for the low loss header.
Installation and maintenance instructions ecoTEC plus 0020261389_02
1
2
3
6 4
5
6
4 External pump for the
decoupled domestic hot
water circuit
5 External domestic hot
water circulation pump
6 Domestic hot water
cylinder
Number Carrying out the
of cir- wiring
cuits
>3 Inform Customer
Service.