20 Nov 86

Symptom: MGTC-20, DXTC-20, DXTH-20 – ERROR CODE P8

Solution: MULTIPLE SOLUTIONS

Cause: OUTDOOR OVERTEMPERATURE/UNDERTEMPERATURE PROTECTION

Remarks:

DESCRIPTION:

WHEN THE ENVIRONMENT TEMPERATURE IS A CERTAIN CONDITION (DESCRIBED IN 1. AND 2. BELOW), THE COMPRESSOR WILL STOP WORKING. AND AFTER 200 SECONDS OF DELAY, THE INDOOR UNIT WILL DISPLAY THE P8 PROTECTION CODE:

1. ON COOLING OR DRY MODE: OUTDOOR UNIT ENVIRONMENT TEMPERATURE: OAT<-20? OR OAT>63?
2. ON HEATING MODE (A OR B):
A. OATò40? OR
B. 30?35?

(PS: OAT—OUTDOOR AMBIENT TEMPERATURE, RT—INDOOR ROOM TEMPERATURE)

REPAIR:

1) CHECK THE ENVIRONMENT TEMPERATURE WHILE THE UNIT IS ON COOLING AND/OR HEATING MODE. IF THE TEMPERATURE IS OUT OF THE SPECIFIED CONDITIONS AS SHOWN IN THE DESCRIPTION (1 AND 2), THE P8 IS A NORMAL PROTECTION

2) CHECK THE LOCATION OF THE OUTDOOR UNIT. IS THERE ENOUGH SPACE FOR VENTILATION?

3) IF THE ENVIRONMENT TEMPERATURE IS NORMAL, PLEASE CHECK THE ENVIRONMENT TEMPERATURE SENSOR AND THE CONCERNED TEST CIRCUIT. IF NEEDED, PLEASE REPLACE THE SENSOR OF OUTDOOR UNIT PCB