heater question

[esoxlucius]

I have 2 aquarline 300W heaters down in my sump. I'm aware that heaters shouldn't be fully submerged because in time water can get inside the tops. So i try and keep the top inch or so of each heater above the water level in my return pump section. However the water level is up and down in my return section due to evaporation and then subsequent top ups so occasionally they are fully submerged. To fully ensure that the tops of each heater are clear of the water surface at all times i'd have to have each one sticking out the surface by about 4" or so. Bear in mind the elements in these particular heaters only covers the bottom 6 or 7" of the tube, in theory i could have the heater only half submerged and the business end if the heater would still be under water and safe????? Right??? Or is it imperative that the heater is fully submerged except for the very tops. Is it the whole heater tube that gets very hot or just the part where the curled up element is?

 

[deeda]

If the heater is rated as fully submersible, it's perfectly fine to run them that way. What do the instructions recommend for your heaters?

 

[esoxlucius]

If the heater is rated as fully submersible, it's perfectly fine to run them that way. What do the instructions recommend for your heaters?

It does actually say that the heater is fully submersible if required so that solves my problem. I thought that all heaters were fully submersible but at the same time there's a risk that water, in time, can get in the tops of them all, that's why people recommend having the tops sticking out. So, unless my heater cracks, there's no way water can get in my heater via the top?

 

[DN328]

Do you happen to have chambers in the your sump? If so, do you have an option to keep the heaters in a chamber that does keep a constant level even with general evaporation? Typically the last one / return pump chamber is where you'll see the fluctuation. I don't keep my heaters there, but I do like constant level, hence have resorted to an ATO to keep consistent water level. At least longer in between fills.

Just sharing a thought, but may not be worth to spend the money just for the heaters in your case.

 

[FreshyFresh]

All heaters I've had have a line marked on them indicating minimum water level.

Lloyd, I'm with ya. "Submersible" heaters can be fully submerged, but they will last longer if you keep the dial end out of the water.

 

[esoxlucius]

Do you happen to have chambers in the your sump? If so, do you have an option to keep the heaters in a chamber that does keep a constant level even with general evaporation? Typically the last one / return pump chamber is where you'll see the fluctuation. I don't keep my heaters there, but I do like constant level, hence have resorted to an ATO to keep consistent water level. At least longer in between fills.
Just sharing a thought, but may not be worth to spend the money just for the heaters in your case.

I have 3 compartments in my sump, 1 and 2 are pretty full with mech and bio. My pump section is the only place to put heaters really unless i start removing my filtration media and i don't really want to upset that lot. My heaters aren't fully submerged all the time anyway but now i know that they are a fully submersible design, i feel more confident on the occasional time when the water level rises and they are underwater.