45
PMML0600 rev.0 - 06/2022
5
INDOOR UNIT DRAINING OPERA
TION
DRAIN AND WA
TER PIPING
5.3.2 Draining operation for YUTAKI H Combi
◆
Draining of the indoor unit
1 Switch OFF the main power supply of the indoor unit.
2
Close the 4 shut-off valves installed at the space heating and outdoor unit connections (Water
inlet and outlet connections).
3 Open manually the drain port for indoor unit water and collect the water into a bucket.
4 Once all the water has been drained, close again the drain port for indoor unit water.
!
CAUTION
When draining the indoor unit water from its drain port, the leaved water could be hot and could
keep in
pressure. Perform the draining procedure carefully.
◆
Draining of the DHW circuit
1 Switch OFF the main power supply of the indoor unit.
2
Close the main DHW inlet valve (water inlet shut-off valve) in order to avoid the tank filling.
3
Open the shut-off valve of the DHW outlet to allow draining without creating a vacuum.
Ensure that valve at the highest level of the DHW system is also opened.
4 Connect a drain hose to the drain port for DHW and lead the other end to the general draining.
5 Open manually the drain port for DHW and wait a long time until all the water has been
removed.
!
CAUTION
When draining the DHW from its drain port, the leaved water could be hot and could keep in
pressure. Perform the draining procedure carefully.
DHWT Drain
Indoor unit drain
