Other Controls - Sanyo 2-WAY ECO-i SPW-C0705DXHN8 Service Manual

5. Other Controls

5-1. Oil Control
5-1-1. Oil level
Oil level Meaning
2 Sufficient
1
1 Slightly low
0 Extremely low
At the time immediately after the oil level changes from 2 to 1, there is a specified amount of oil in the compressor. Namely,
soon after the oil level is changed to 1, the oil in the compressor is not empty. If the oil level "0" indication continues for
more than 5 to 10 minutes, it seems short of oil in the system. Check for any oil leakage as well as the refrigerant tubing.
5-1-2. Oil level detection
Excess oil in the compressor is sent by bypass via a capillary tube to the low-pressure circuit. The temperature
detected by a temperature sensor is used to determine whether it is oil (warm) or refrigerant (cold).
5-1-3. Self-separator oil recovery control
* When a low oil level is detected, this control recovers the oil which has accumulated in that oil separator and
sends it to the compressor.
(1) Operation when oil level is not 2.
30 seconds after the oil level changes from 2 to 1, the recovery valves turn ON.
However, if the oil level becomes 2, this control is stopped.
5-1-4. Unit refrigerant oil recovery control – utilizing balance tubes
* If the low oil level continues, that outdoor unit (oil-receiving outdoor unit) receives a supply of oil from operating
outdoor units where the oil level is not low (oil-supply outdoor units).
(1) Control at the oil-supply outdoor unit begins 3 minutes after the oil level at the outdoor unit dose not become 2.
Oil supply is performed for a maximum of 5 minutes from each unit.
(2) When oil supply is ended, oil supply from that outdoor unit will not occur again for a period of [(No. of outdoor
units minus1) x 5 minutes]. In addition, oil supply is ended if the oil-receiving outdoor unit oil level changes to 2,
or if the oil-supply outdoor unit oil level becomes low.
(3) The supply of oil is received from 1 unit at a time, in sequence, according to the order of priority of their inverter
compressors.
(4) Operation during unit refrigerant oil recovery
(A) Oil-receiving outdoor unit
The recovery valve turns ON and remains ON.
(B) Oil-supply outdoor unit
The balance valve turns ON and remains ON.
The bypass valve repeatedly turns ON and OFF according to a constant cycle.
5-1-5. Indoor unit refrigerant oil self-recovery control
Refer to the items concerned with indoor unit special control.
Conditions of oil
The compressor contains oil more than
the oil level which is necessary and
sufficient for normal operation.
The compressor contains sufficient oil
but there is a possibility of shortage
against the required oil level.
The compressor oil is short against
the required oil level sufficient for normal
operation.
1 - 14
W-2WAY ECO-i SYSTEM
Control Functions
Judgement
There is no problem.
Confirm that oil is returned after
performing the oil control operation.
Confirm that oil level is recovered to the
required level after performing the oil
recovery control between systems.