Fitting The Flow Temperature Sensor, Secondary Circuit - Viessmann Vitocal 300-A Series Installation And Service Instructions For Contractors

Installation sequence
Making the hydraulic connections
Note
■ In underfloor heating circuits, install a temperature
limiter to restrict the maximum temperature of under-
floor heating systems.
■ Ensure minimum flow rate: see "Specification".

Fitting the flow temperature sensor, secondary circuit

The flow temperature sensor for the secondary circuit
is installed in the heating water flow inside the build-
ing.
Note
If an instantaneous heating water heater is installed, fit
the flow temperature sensor for the secondary circuit in
the heating water flow downstream of the instantane-
ous heating water heater.
3.
C
D
2.
Fig. 10
Pipe section with sensor well
A
Spring clip
B
Flow temperature sensor, secondary circuit
C
Sensor lead plug and lead to the heat pump con-
D
trol unit
Connecting the condensate drain
Note
■ Subject to temperature and relative humidity of the
drawn air, up to 20 l of condensate per hour can
occur in the appliance.
During the defrosting process, the amount of con-
■
densate can be as high as 20 l within 5 min.
18
(cont.)
1.
A
B
1. Fit the pipe section with a sensor well.
2. Secure the flow temperature sensor for secondary
circuit with a spring clip in the sensor well.
3. Connect the sensor lead and the lead to the heat
pump control unit.
4. Connect the lead to the heat pump control unit to
the controller and sensor PCB inside the heat
pump control unit at connection F8. If necessary,
extend the lead to the heat pump control unit on
site.
■ Connect the condensate drain via the trap (backup
level at least 60 mm) in the frost-protected area to an
on-site drain connection (drainage or sewer system):
See page 12.
Route condensate drain (drain pipe DN 40) with a
■
constant fall of at least 2 %.
■ Where appropriate, provide thermal insulation or a
ribbon heater around the condensate drain on site.