redearslider.com

I have had a couple fx5 for a few years now and they have worked flawlessly. Lately, one keeps shutting off and not starting back up. I empty it and clean the filters and impeller and it starts backup just fine. Problem is within 1-2 days it shuts off again and won't start backup until I clean it again. Any ideas?

Possibly the computer chip might be going bad, since the moter will still run. Thats the most logical explanation i can think of. If it that, your in trouble searching for that assembly with that chip it costs over $100

Not sure when you got your filter, but the FX5 comes with a 3 year warranty from Hagen (fluval's parent company)

Quotes from Hagen support:

"If a problem does arise, which may cause further damage to the filter, the smart-chip will shut down the filter. Some possible problems which may cause the unit to shut down are: a damaged or defective impeller, an air leak, clogged media, a problem with the actual motor, very dirty impeller well area, etc."

"As soon as it recognizes a potential damaging problem, it will shut itself down. The unit will not turn itself back on until the problem has been corrected. The chip recognizes a problem when there is a reduced flow rate, or an inconsistency of the flow rate."

-----

While it could be the chip going bad (expensive as DB4L mentioned), I would try the cheap fixes first. The two things that jump out at me are the impeller and the air leak. If you have a very long screwdriver, you can take the motor assembly off of the EMPTY canister. Inspect the impeller for any damage. Inspect the o-ring and lubricate that thing with some petroleum jelly. If the o-ring is dry lubricating it might fix it. If the o-ring has dried out and has cracked, you'll need to replace it. The impeller if nicked or if there are any plastic shavings or crud around it will slow down the flow rate and cause that smart chip to shut it off. Impellers die... You'd be surprised how the most minuscule damage causes those things to not function.

The impeller by itself is $40 online and Big Al's (online petstore) carries the motor assembly with housing (includes the smart chip) and impeller for $90.

Id check a petstore for parts, i know local petstores carry fx5 parts, and works out to be cheaper without the shipping or time waiting.

I will say though I question actually how good the chip sensory is from that quote. I have had that media so bad and i actually had a problem from my driftwoof falling apart it got into the impeller caused it to run poor and make some pretty bad noises. I wish it would have shut it down then but that thing kept running. Nothing like cleaning that filter in freezing weather. Though try everything Veipa said. I should just leave filter questions to him lol.

Thanks for the response. I have really cleaned the housing and impeller and I have taken out all media for now to see if it stops again. 24 hours so far so good.