Heater Location

[cameron]

I have been considering putting my heaters in my overflows. The main reason is that if the return pump dies, my tank would remain heated (maybe). I have considered going to two returns or placing a flow detector on the return, but looking at it I can live quite a while without a return pump except heat. I can easily fit one in each overflow for some level of redundancy.

Now the questions... since my overflows are those black Oceanic ones do you think the heat will radiate well enough to actually use? I don't want to boil the water in the overflows to get warmth in the tank.

Where should I locate my primary temp probe if I try this? I can't put it in the overflows as they will likely be warmer than anything else in the tank.

Last question, anyone already doing this with any success?

 

[victor626nj]

i would think not ...you best bet would be to use them behind the rock and run the cord on the side of the overflow ..like you did with the air pump hose

 

[wbholwell]

Mine is in my overflow, but not for the reason you stated (my temp probe is also in my overflow.)

I think it could be done, but calculating how much higher the temp in the overflow must be to maintain the temp in the display is a pretty complicated thermodynamics problem.

Worst case scenario, I don't think the water in my overflow would have to be more than 15 deg. higher than the display's. The main problem this could cause would be a complete die-off of everything living in my overflow.

 

[cameron]

Victor626nj;122455 wrote: i would think not ...you best bet would be to use them behind the rock and run the cord on the side of the overflow ..like you did with the air pump hose

Those are going. I have a new idea for maintaining flow in a power outage. I would rather not have the cords showing.

I am probably going to block light from the overflows soon enough so I expect some die off anyway.

Anyone any good at figuring heating calculations based on thermal mass?

 

[wbholwell]

Cameron;122476 wrote:
Anyone any good at figuring heating calculations based on thermal mass?

Heat transfer rates can vary widely depending on different conditions (i.e. if your house is breezy or not.) A better way to find out if this will work would be to turn off the return pump for 3 or 4 hours, and measure the fluctuation of temp in the display. If it constantly falls throughout the entire experiment, then chances are it won't work. Also, stick a thermometer in the overflow to measure its temp at the same time.

 

[ronnieblaze]

i have my heater in my overflow and my temp probe in my sump.. and so far no heat problems once i got the heater dialed in

 

[dannybradley]

I've run heaters inside of overflows many time with no issues. I think you'd be fine to try it. The worst case would be you having a lower temp. I don't think that the heat would transfer from the overflow to the tank at an appreciable rate in the event of a pump failure. However, it may warm the overflow enough for the fish to at least gather around it.

 

[skriz]

one of mine is in the overflow. I don't have an issue with the tank's temp being too low, so I can't tell you if it will work or not in case of pump failure.

 

[cameron]

I guess the best thing is to just throw them in there, shut down the return and monitor everything. Was hoping someone already tried it.

 

[dakota9]

Mine is in the overflow, as its too long to fit in the sump.

Your Idea can't work because the theory is flawed. If your return pump goes out, and heater is in the overflow, then your overflow will will stay a nice 80 degrees while the rest of the tank gradually grows colder. The thermostat in the heater will turn it off at 80 degrees. Theres no way the few gallons of 80 degree water in the overflow is going to warm the water in the display. Putting the heater in the display its self wold be the best way arouind this. Also, I would think the plastic/acrylic the overflow is made of wouldn't transfer heat as well as glass, and would work more to insulate the overflow, rather than disapate heat into the display...

IMHO

 

[wbholwell]

No, the theory isn't flawed as long as the thermostat probe is seperate from the heater, and placed in the main display.

 

[cameron]

WB is correct at least to a point. I wouldn't let the water i the overflows get above say 100. With the flow in the tank, there should be some thermal exchange between to the areas. I am just affraid all that plastic is too good of an insulator. I will try this probably this weekend and see how it turns out.

 

[wbholwell]

I might do the same. You've made me curious, Cameron.

 

[cameron]

If it works in heating the tank reasonably well, it is a superior location IMO. Less things can go wrong. If it doesn't work, back to the drawing board for more tank redundancy.

 

[glxtrix]

I would think that the plastic would retain too much of that heat and the internal temp sensor on the heaters would turn them off. Unless you have one of those heaters that uses some other source of temp reading.

 

[schwaggs]

Cameron;122476 wrote:
I am probably going to block light from the overflows soon enough so I expect some die off anyway.

Don't forget about the host of animals that don't need light like sponges, etc.