Haier MRV5-H - 6.4.8 High Discharge Temperature Control; 6.4.9 Low Discharge Temperature Control

66
6.4.8 High Discharge Temperature Control
·Td high temperature side (≤248°F) is controlled by the “indoor unit SH correction + SV3 LEVb control + compressor
frequency control”. (Note) Compressor frequency control is performed by fuzzy logic control.
When the discharge temperature Td≥203°F, the SV3 is turned on.
When the discharge temperature Td≥221°F, the compressor reduce the frequency
When the discharge temperature Td ≤ 194°F, Recovery usually control
6.4.9 Low Discharge Temperature Control
In cooling:
·Td low temperature side (<CT+50°F) is controlled by the rst stage is indoor unit SH control/ the second stage is
compressor output control/ the third stage is minimum number of outdoor units running control.
Normal operation
(Indoor SH
constant control)
Normal operation
(Indoor SH
constant control)
Compressor output
correction control
Min. number
control of
outdoor unit
(Td SH 59°F constant)
·<CT+68°F
·<CT+77°F
·<CT+59°F
Protection
stop
Error stop
·<CT+50°F
Error stop
Protection
stop
*Restart after 3 minutes
·<CT+59°F
·≥CT+15 68°F
·Correction
control completed
Indoor SH
correction control 2
(Td SH 68°F constant)
·≥CT+68°F
·≥CT+77°F
(TdSH20°C constant)
Min. number
control of outdoor
unit
·<CT+68°F
·<CT+50°F
·≥CT+20 77°F
·Correction
control completed
·Correction control completed
·Correction control completed
·<CT+50°F Lasts 5 minutes
·&
·&
·&
※
Indoor SH
correction control
2
※
Compressor rps
3 correction control
※
Locked if it occurs 3 times in an hour
※
In heating:
·Td low temperature side (<CT+50°F) is controlled by the rst stage is indoor unit SH control/ the second stage is
compressor output control/ the third stage is
minimum number of outdoor units running control