# Aqueon Pro heater flashing red light?



## jf7304 (Oct 26, 2015)

This morning before work, I noticed my heater didn't seem to be operating properly. It's an Aqueon Pro (the solid black one, NOT glass). The green light is illuminated, and every 5 seconds or so, the light will flash red once very quickly. In another 5 seconds or so, it will flash red twice quickly. It repeats this cycle over and over (1 red blink, green, 2 red blinks, green, one red blink, etc.....). Is this flashing some type of error code? It's always kept my tank at a solid 80°, where now, it's made it down to 74°. I was on my way out the door for work, so I didn't have a lot of time for troubleshooting. Has anyone else ever ran into this problem before? It's been a great and reliable heater until now...


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## gillmanjr (Jan 27, 2017)

I remember this happening with mine once, but I have no idea why it was happening. Try unplugging it and plugging it back in. If that doesn't work try changing the temperature setting until it goes into heating mode, then put it back where you had it.


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## knadams (Mar 1, 2015)

Had the same problem, give them a call or an email, they should replace it. I think they're aware of the default as they did mine without any questions asked


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## Narwhal72 (Sep 26, 2006)

There are no error codes with this heater. This sounds like a thermostat failure. The NTC has failed and is not signaling that the heater needs to activate properly. Contact Aqueon Customer Service and get it replaced.


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