Trane 4TVH0086FE000AA Service Manual page 33

Oil return operation in heating mode and defrosting operation
Figure 2-3.7: 14/16/18HP refrigerant flow during oil return operation in heating mode and during defrosting operation
High temperature, high pressure gas
High temperature, high pressure liquid
Medium temperature, medium pressure gas
Low temperature, low pressure
E S C
6
5
4
3
2
T7C1
1
9
Heating operation
Figure 2-3.8: 14/16/18HP refrigerant flow during heating operation
High temperature, high pressure gas
High temperature, high pressure liquid
Medium temperature, medium pressure gas
Low temperature, low pressure
E S C
6
5
4
3
2
T7C1
1
9
11
10
7
T3
T4
SV5
15
11
10
7
T3
T4
SV5
15
13
8
EXVA
14
EXVC
12
13
8
EXVA
14
EXVC
12
32
Unit on
Fan
Thermostat on
off
Filter
Filter
480 steps
Unit on
Fan
Thermostat on
off
Filter
Filter
480 steps
Unit off
Fan
off
Filter
Filter
480 steps
Unit on
Fan
Thermostat off
off
Filter
Filter
480 steps
Unit on
Fan
Thermostat on
on
Filter
Filter
Normal control
Unit on
Fan
Thermostat on
on
Filter
Filter
Normal control
Unit off
Fan
off
Filter
Filter
Closed
Unit on
Fan
Thermostat off
on
Filter
Filter
Closed