How long should your heater run?

[BeanAnimal]

Does seem liek a very long time to be continuously heating the water - Id understand if it was heating from zero but just to keep the temperature where it is they are on that long - Just seems very odd.

Have you checked both are working and actually producing heat?

Are the heaters internal thermostats set to a degree or two higher than the inkbird controller? Heater thermostats are fairly inaccurate in the grand scheme of things - Your inkbird might be turning the power on to the socket but your heater may be cutting that power if not - And not fully heating the water how it should.

Not sure you read any of the posts above

same points already made with some math (yuck) too. But you are correct, in the assumption that the logic is backwards and the inkbird needs to control and the heater's internal thermostats need to act as failsafes

 

[LiamPM]

Not sure you read any of the posts above

I sure did - then added another, this time being my own, opinion to the equation joining the forum discussions

 

[TheBear78]

I think it's a common theme for the time based alarm to go off when first setting up an Inkbird. I recall several threads about it and mine certainly did at first before I upgraded the heater.
I was running a single 300w in my 100 gal (I optimistically trusted the manufacturer) but it would never reach 25 C.
I subsequently added another 300w and it was fine except on the coldest days, typically in the spring when the house heating is off but it's still fresh. I've since switched to two 350w titanium heaters and it's much happier.

An important aspect of the time based alarm is that for those of us not running an Apex or similar it can warn of a return pump failure. I have my probes (Inkbird ITC-306a) in the drain chamber of my sump and the heaters in the next chamber which happens to be the skimmer. If the pump fails the heaters will not heat the drain chamber very fast and the alarm will trip. Looking at the trend chart on the inkbird app shows that my heaters are typically powered on and off about an hour each way. I've set my alarm to three hours and it has never triggered during normal operation.
FYI, I have T1 and T2 set at 25.0 and 25.3 C respectively.

 

[vatedome04]

Running 10 to 15 minutes per cycle seems acceptable. So is running as long as 20 minutes. Even running every seven or eight minutes may not be a problem, as other factors could lead to more frequent cycling.