5.4.5 Application 5
Space heating with an auxiliary boiler (alternating operation).
Space heating application by either the unit or by an auxiliary boiler connected in the system.
■ The unit controlled contact (also called "permission signal for the auxiliary boiler") is required on-site, and it is recommended that the
signal be determined by the outdoor temperature (thermistor located at the outdoor unit).
■
Application A
can be used if the auxiliary boiler replace the unit provides heating for space heating.
■
Application B
can be used If the temperature of water from the outdoor unit is not high enough. An additional 3-way valve should be
installed, if the temperature of water from outdoor unit is high enough. The boiler will then be bypassed. When the temperature is not high
enough, the 3-way valve will open and the water from outdoor unit will flow through the boiler and be heated again.
NOTE
If you need to connect an auxiliary boiler (or other additional heating source) and can control auxiliary boiler, you need to
customize.
CAUTION
Be sure that the boiler and the integration of the boiler in the system is in accordance with relevant local laws and regulations.
Application A
4
AHS
1
5
10
5
9.1
11
12
9
2
3
8
9.2
6
7
FCU1
FCU2
FCUn
1
outdoor unit
2
Y-shape filter
3
shut-off valve (field supply)
4
wired controller (optional)
5
non-return valve (field supply)
6
drain valve (field supply)
7
fill valve (field supply)
8
buffer tank (field supply)
9
balance tank (field supply)
9.1 air purge valve
9.2 drain valve
10 expansion vessel (field supply)
11
Pump 2: outside circulation pump (field supply)
12
collector (field supply)
FCU 1...n fan coil units
AHS additional heating source
18
