More support for a heater controller...

TheEngineer · Oct 28, 2015

I'm a big proponent of controllers for all heaters. At the very least they are a second line of defense should the heater get stuck in the on position. I noticed something unusual in my tank today...my heater has decided to follow a lower temperature.

You can see in this image that the temperature starts to drop and then oscillates there and then again at a couple of other temperatures. Looking at the relay activity, the heater has been left "On" 24/7 for the entire period shown here. So the heater thermometer is bouncing all over the place. For whatever reason, I've thought heaters would over-heat, but hadn't considered under-heating.

Just thought I would share...

EDIT: The controller is set to keep the temp between 78 and 79.

prdubois · Oct 28, 2015

Your in PA. Has your room temp changed?
Did the weather get colder outside?
Did it get warmer outside and you turn off the heater in the house?

abecker · Oct 28, 2015

Have you checked to ensure the heater itself is functioning properly. I had a glass heater that got water in the tube and it would typically shut off, but I noticed from time to time it would come back on.

TheEngineer · Oct 28, 2015

prdubois said:
Your in PA. Has your room temp changed?
Did the weather get colder outside?
Did it get warmer outside and you turn off the heater in the house?

It has changed and that was my first thought. However, the heater is clearly turning on and off. It isn't just sitting on. The house is generally between 65 and 70 so it wouldn't be warm enough to push tank temp up.

abecker said:
Have you checked to ensure the heater itself is functioning properly. I had a glass heater that got water in the tube and it would typically shut off, but I noticed from time to time it would come back on.

It appears to be functioning, albeit following some mystery temperature setting.

abecker · Oct 28, 2015

Does the heater have an internal thermostat?

TheEngineer · Oct 28, 2015

abecker said:
Does the heater have an internal thermostat?

It does. I'm assuming that's where the problem lies. Seems strange that it jumps around though.

abecker · Oct 28, 2015

icecool2 said:
It does. I'm assuming that's where the problem lies. Seems strange that it jumps around though.

Yeah, though it is possible if the temp setting in the heater had changed or if it is just off by a bit and it shutting the heater off around 78 plus a little carryover. If the reef angel is controlling the temp I would try setting the heater on 80 and see if it comes back up to temp. What heater are you using?

TheEngineer · Oct 28, 2015

Yeah, I had it set to 80 already thinking that would be the second level defense. I upped it a bit to see if it helps. It is a Hydor Theo. I've always used them (albeit with a controller) and had good luck with them. Maybe I should get a different one...

prdubois · Oct 28, 2015

You have not changed Lights, Pumps or anything else that could have been heating your water some? Looks like the heater internal thermostat may be bad.

TheEngineer · Oct 28, 2015

prdubois said:
You have not changed Lights, Pumps or anything else that could have been heating your water some? Looks like the heater internal thermostat may be bad.

Correct, no equipment changes. I guess I should pick up a new heater. I turned up the temp on it more and I'll see where it settles out at a higher temp or if it still bounces around.

ngvu1 · Oct 28, 2015

I always plug the heaters to an external controller for double protection. I have heard enough stories about how heaters went bad and cook the whole tank up. There are many cheap solutions out there.

TheEngineer · Oct 28, 2015

ngvu1 said:
I always plug the heaters to an external controller for double protection. I have heard enough stories about how heaters went bad and cook the whole tank up. There are many cheap solutions out there.

Yep, and mine is plugged into one for that reason too. The one I didn't count on was the heater thinking it was at temp and turning off prematurely.

ngvu1 · Oct 28, 2015

You can always crank the heaters up right?

icecool2 said:
Yep, and mine is plugged into one for that reason too. The one I didn't count on was the heater thinking it was at temp and turning off prematurely.