New Fluval E300 heater problem?

[i3k]

Purchased a brand new Fluval E-300 heater and I'm a bit concerned. I installed it fully submersed not touching the sand. I set the heater to 75 degrees. After the heater was set, the LCD went back to showing current water temp. It was on 71.5 when I set it. It has now been 2 hours since and the heater LCD is still showing 71.5. However, the digital thermometer on the other side of the tank is now showing 75.6. It was showing 72 before I installed this new heater.

Anyone with this heater know what the deal is? Broken thermometer sensor? It's clearly heating up the water just not showing temp changes on the LCD.

 

[rlederer]

Two hours isn't enough time to give you a decent reading. Depending on the size of the tank and the circulation pattern, it might be a day before you will get accurate readings. Plus, inexpensive thermometers are usually inaccurate by a degree or two. I wouldn't worry about it yet.

 

[i3k]

It's in my 100gal tank and I have a canister filter and also have a powerhead going. I know these heaters have microprocessors that need to detect good water flow and I think I have more than enough circulation going on.

I went ahead and unplugged the heater for a few minutes. Plugged it back in, and it was showing 75.0. After about another 10-15 min, it is now showing 75.5. Hopefully it won't boggle down on me again.

 

[i3k]

This heater has been keeping steady temperature until today. It was a bit warmer than usual today and the temperature went up from 75.5 to 77.5 degrees. The LCD started to flash red and green back and forth. Is this normal? Is the warm alert set to 77 degrees? I would think at 79-80 is when the alert should be triggered.

EDIT: NVM. I found the answer I was looking for. The alert starts flashing if the preset temperature changes by 2 degrees up or down. Makes sense. I just wish it didn't flash between red and green.