Service Functions; Compulsory Defrosting Mode For Service; Change In Defrost Setting; Timer Short Mode - Mitsubishi Electric MSH-18RV Service Manual

10

SERVICE FUNCTIONS

MSH-18RV - MUH-18RV -
E1
MSH-24RV - MUH-24RV -
E1
MSH-30RV - MUH-30RV -
E1

10-1. COMPULSORY DEFROSTING MODE FOR SERVICE

By short circuit of the connector JP607 and R853(MSH-18RV)/ JPG1 and R871(MSH-24/30RV) on the outdoor deicer P.C.
board, defrosting mode can be accomplished regardless of the defrost interval restriction. (Refer to page 69 or 70.)
Defrost thermistor RT61 must read below -3°C.

10-2. CHANGE IN DEFROST SETTING

MUH-18RV
<JPC> When the JPC wire of the deicer P.C. board is cut, the defrost interval time will be changed.
<JPE> When the JPE wire of the deicer P.C. board is cut, the defrost temperature will be changed. (Refer to page 69.)
MUH-24/30RV
<JRF> When the JRF wire of the deicer P.C. board is cut, the defrost interval time will be changed.
<JRG> When the JRG wire of the deicer P.C. board is cut, the defrost temperature will be changed. (Refer to page 70.)
Model
MUH-18RV -
E1
Model
MUH-24RV -
E1
MUH-30RV -
E1

10-3. TIMER SHORT MODE

For service, set time can be shortened by short circuit of JPG and JPS the electronic control P.C. board.
The time will be shortened as follows.
Set time : 1 minute
Set time : 3 minute
10-4. P.C. BOARD MODIFICATION FOR INDIVIDUAL OPERATION
A maximum of 4 indoor units with wireless remote controllers can be used in a room.
In this case, to operate each indoor unit individually by each remote controller, P.C. boards of remote controller must be
modified according to the number of the indoor unit.
How to modify the remote controller P.C. board
Remove batteries before modification.
The board has a print as shown below :
The P.C. board has the print "J1" and "J2". Solder "J1" and "J2" according to the number of indoor unit as shown in Table 1.
After modification, push the RESET button.
E1
E1
E1
Jumper wire
Defrost interval time changes from 40 minutes to 15 minutes.
JPC
Defrost start temperature changes from -3: to 0:.
JPE
Defrost finish temperature changes from 3: to 10:.
Jumper wire
Defrost interval time changes from 40 minutes to 15 minutes.
JRF
Defrost start temperature does not change.(-3.0:)
Defrost finish temperature changes from 3: to 15:.(MSH-24RV)
JRG
Defrost finish temperature changes from 13: to 15:.(NSH-30RV)
1-second
3-second (It takes 3 minutes for the compressor to start operation. However, the starting time is
shortened by short circuit of JPG and JPS.)
Change point
Change point
NOTE : For remodelling, take out the bat-
50
teries and push the
OPERATE/STOP(ON/OFF)button
twice or 3 times at first.
After finish remodelling, put back
the batteries then push the RESET
button.