Haier HPU-20CU13 User Manual - Page 25

Trouble shooting Before asking for service, check the following first. Phenomenon The system does not restart immediately. Noise is heard: Normal Performance inspection Smells are generated. Mist or steam are blown out. Cause or check points When unit is stopped, it won't restart immediately until 3 minutes have elapsed to protect the system. When the electric plug is pulled out and reinserted, the protection circuit will work for 3 minutes to protect the air conditioner. During unit operation or at stop, a swishing or gurgling noise may be heard. At first 2-3 minutes after unit start, this noise is more noticeable. (This noise is generated by refrigerant flowing in the system.) During unit operation, a cracking noise may be heard. This noise is generated by the casing expanding or shrinking because of temperature changes. Should there be a big noise from air flow in unit operation, air filter may be too dirty. This is because the system circulates smells from the interior air such as the smell of furniture, cigarettes. During COOL or DRY operation, indoor unit may blow out mist. This is due to the sudden cooling of indoor air. Multiple check Does not work at all. Poor cooling Is power plug inserted? Is there a power failure? Is fuse blown out? Is the air filter dirty? Normally it should be cleaned every 15 days. Are there any obstacles before inlet and outlet? Is temperature set correctly? Are there some doors or windows left open? Is there any direct sunlight through the window during the cooling operation?(Use curtain) Are there too much heat sources or too many people in the room during cooling operation? 24