AC unit sparks (flash of blue light) on startup.

[ron045]

50 Amp Service

GE Air conditioner, model ARC15AaCBL2

Last night I thought I saw a flash of lightning. A gentle blue light flashed for just a brief second.

A little while later, it happened again, except we noticed it happened when the AC turned on.

I tried to raise and then lower the thermostat to cycle the AC and I could not replicate the problem. But during the night we noticed it happened 4 times. It does not seem to happen every time.

But when it does happen, it's when the AC kicks on. So we don't think it's anything else.

At least three of the four times no other major appliances were running. No microwave... although maybe the fridge. I did not think to monitor that.

One instance the shower was in use, so we know the on demand hot water heater was on. But that is gas, with an electric start however.

I know the compressor needs a lot of energy to get started and then the power cycles down for regular running. So is this just a normal start up of needing extra power to get the compressor running or do I have a problem?

Thanks.

Ron

[howson]

So is this just a normal start up of needing extra power to get the compressor running or do I have a problem?

An air conditioner compressor does require extra power to get going (thus the reason for devices like MicroAir's EasyStart), but a flash of light visible from the ground (or inside?) is definitely not normal. I believe there's a problem that won't get better on it's own.

Howard

P.S. Whether you troubleshoot yourself or have someone else look at it, please come back and document what was found.

[Country Campers]

If you want to tackle this yourself I would remove the inside trim panel and look up into the plenum to find the control box, or any other wire connections you may see, and make sure there are no loose connections. Please make sure all power is disconnected before doing this. A blue flash could mean a loose wire making an arc which is not good at all.

Brian

[ron045]

Just reporting back and closing this one out. We did some testing the other night. We started by cycling the AC in the dark. Nothing. No flash or spark.

Then, one by one we would turn on a light and cycle the AC until we could replicate the problem. Dining table light, microwave light, overhead lights and a table lamp.

All were LED except the table lamp. When the table lamp is on and the AC cycles on the extra draw of power makes the lights dim or flash so quickly that is looks like a blue flash.

I put my hands up by my face to shield my surroundings and focus on the AC. No spark and no flash from the AC. It's the dimming of the lights that look like a flash of blue.

Thanks all for the inputs.
Ron