Viessmann Vitocal 300 AWO-M-AC 301.A, Installation And Service Instructions Manual

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109
1. Open any on-site non-return valves if
installed.
2. Check the pre-charge pressure of the
expansion vessel (see the following
chapter).
3. Fill (flush) and vent the secondary cir-
cuit via an on-site connection.
4. Check the system pressure at the
pressure gauge (on site) and top up
with water if required.
Minimum system pressure: 0.8 bar
Permiss. operating pressure: 3 bar
5.
!
Please note
To prevent equipment dam-
age, check the flow and return
connections of the heat pump
secondary circuit for
leaks .
In the case of leaks, drain off
water and check the seating
of the seal rings. Replace any
seal rings that may have
become dislodged.
6. Close drain & fill valve.
7. To prevent damage to electrical com-
ponents, connect an on-site hose to
manual air vent valve
A and open
the valve.
8. Only type AWCI-M-AC 301.A:
To vent, set 3-way diverter valve for
"Central heating/DHW heating"
B to
its central position. For this, lock the
manual lever in its l.h. position.
9. Close manual air vent valve A after
complete venting.
10. Check the system pressure and top
up with water if required.
Checking the expansion vessel and heating circuit pressure
Carry out this test on a cold system.
Note
Only use anti-corrosion agents that have
been approved for heat pumps with
DHW heating via single-walled heat
exchangers (DHW cylinders).
1. If an on-site shut-off valve is installed,
close it.
Otherwise drain the heating system
on the heating water side until the
pressure gauge indicates "0".
2. If the pre-charge pressure of the
expansion vessel is lower than the
static system pressure, top up with
sufficient nitrogen to raise the pre-
charge pressure of the expansion
vessel to 0.1 to 0.2 bar above the
static system pressure.
Example:
Static head (distance between the
heating appliance and the highest
heating surface (radiator, underfloor
heating surface etc.) 10 m
Commissioning, inspection, maintenance
Further details regarding the individual steps
(cont.)
5692 875 GB
Service