Blinking Lights.

Portable AC units previously in cooling mode might take up to 5 minutes to switch over to heat mode. The unit has a safety circuit which prevents the compressor from switching too quickly and drawing excessive current. Select heat mode then wait approximately 5 minutes to allow the compressor too cool down then switch to heat mode. After about 4 minutes the compressor will come on and then after an additional 1 minute the fan will turn on to produce warm air.

Or if you see in the display E, E1, or E4, or STOP: See https://www.haieramerica.com/support/faq and drill down to the page for portable air conditioners, on which those errors are explained.

If the above doesn't solve, unplug the unit from the wall and press the reset button on the power plug. On occasion a power surge can cause the circuit breaker to open and prevent the unit from operating. Additionally, please verify that the outlet you're using is working properly. If you continue to have problems you'll need to contact Haier America at 1-877-337-3639, or visit http://www.haier.com/us/servicesupport/repairs/ to arrange service.

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