Control Of Bc Controller; Control Of Sva, Svb And Svc; Control Of Svm; Control Of Lev - Mitsubishi Electric PUHY-200YMF-C Service Handbook

[2] Control of BC Controller

(1) Control of SVA, SVB and SVC

SVA, SVB and SVC are turned on and off depending on connection mode.
Mode
Connection
SVA
SVB
SVC

(2) Control of SVM

SVM is turned on and off corresponding to operation mode.
Operation mode
SVM

(3) Control of LEV

LEV opening (sj) is controlled corresponding to operation mode as follows:
Operation mode
LEV1
LEV3
Superheat
*1
control
Differential
*2
pressure control
*3
–
* Please confirm that the above parts of BC controllers are being color-corded and shown with the name plate inside
the BC controller unit.
Cooling
ON
OFF
ON
Cooling-only Cooling-main
ON OFF
Cooling-only Heating-only
2000 60
Superheat Differential
control *1 Pressure control
*2
Control every minute so that superheat amount detected by bypass inlet and oulet
temperatures (TH12, TH15) stay in the specified range.
Control every minute so that detected differential pressure (PS1, PS3) stay in the
specified range.
60 or more pulses are sometimes detected because of rise in liquid side pressure (PS1).
Heating Stop
OFF OFF
ON OFF
OFF OFF
Heating-only
OFF
* SVM is not built in depending on models.
Cooling-main
• Liquid level
control *3
• Differential
Pressure control
pressure control
*2
–63–
Defrost
OFF
OFF
OFF
Heating-main Stop
OFF OFF
(Number of pulse)
Heating-main Stop
60 2000
Differential
60
*2