Do not underestimate how much heat "that little 500gph pump" puts into your system. This pump is pumping sustained 60F liquid and holding just under 100F body temp.
Posted Feb 2, 2022, 3:40 AM UTC
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Oh geez
Makes me wonder if I should put my air pump on an interval timer because I noticed it also puts out a little bit of heat as well 🧐
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I put my air pump in a cooler environment (not cold, but cooler than in my tent) and run the lines into the tent. This way it pulls “cooler” (obviously the pump itself still adds heat but it is reduced by the cooler input) air directly into my buckets. I am however running individual DWC containers with no water pump
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This makes sense
I currently have my air pump hanging in the canopy of my grow tent because I wanted to contain the noise
But I suppose I should try and relocate it out of the tent and see if it helps reduce the overall ambient temperature of the tent
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That is very fair as I do of course have to tolerate the extra noise. I must admit I only noticed it at night time but I find the dull hum somewhat therapeutic next to my tinnitus.
If nothing else I would suggest lowering your pump, it’ll only save you a few degrees but with hot air rising to the top of your tent every little helps! This with a low level air inlet (not an option for me sadly as my cats love to use the lower vents as TUNNELS if I leave them open) and high level exhausting of warm air should help reduce your temperatures
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Is the intake ambient tap water? I was wondering how much heat is being added. I guess the real question is, if we used two vessels filled at the same time and allow them to stabilize more or less, where does one with a pump go compared to one without a pump. There will be some difference with volume. I guess I can find out easily enough. I have venturis running off 800GPH submerged pumps in totes with 7'5 gallons, and I can easily fill an identical tote that has none.
I didn't check when I had air running, but the one 38W air pump that was serving six tanks got too hot to pick up by hand so it had to be sinking some heat via the air lines.
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I am tuning my water chiller and it is currently set to 60 degrees. The water chiller and pump have been running for 30 hours. So I am confident everything has stabilized in the 70F environment. So the tubes, pump, bucket, and chiller are in 70F degree air, circulating 60F degree water through a (nearly) 100F degree pump.
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That doesn't sound bad, but you made me wonder, and I think I'll set up the test tomorrow and let it stabilize and see what happens with the submerged pump.
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Making people wonder is why I made the post. Many people take an "ah itt'l be fine" approach then come back with root rot. They think their water is 72 when it's probably 82+.
For what it's worth the 300 gallon per hour version of this pump got up to 90F sustained in the same 30hr test.
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At the moment, I run my F&D cycles on a 6 min ON / 15 min OFF, so I’ve been assuming it’s not affecting the water temperature.
But now I may want to keep a closer eye on it, so thanks for this post in effort to raise awareness.
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Gives you some idea of how vigorous aeration needs to be. I know I need a lot because my nutrient is warm most off the year. Fortunately, I never have root rot.
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I sanded a flat spot on my air pump and threw a Corsair h50 on it, temps are 15-20 degrees cooler than before.
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These pumps are generally encased in an epoxy which syncs the heat out into the housing and dissipates it out through the body of the pump rather than out into the fluid through the pump. In water cooling for pc's I believe they calculate like 18W of heat being introduced into the system from the pump, which is a gross overestimation in my opinion being as the pumps themselves only pull 18w, not all of the heat goes into the water if you catch my drift, that's why the body of the pump is heating up. But with that number you can calculate the amount that will heat up a 5 gallon bucket of water pretty easily, it would take 3.5 hours for 18w to heat a bucket of water from 65f to 70f given there's no heat dissipation from the system.
Given the bucket has square 777 inches of surface area (roughly), the material is made of hdpe with a thermal conductivity of .51 so the limiting factor is the thermal conductivity of air which is .025 if the bucket is at 75 degrees it will dissipate 24w into the air through the bucket if the room is at 70. therefore it should not give any noticeable rise to temperature unless your pump is consuming more than 24w with absolutely no heatsyncing, granted as the temperature difference rises the dissipation goes up, so if its 65 in the room the bucket at 75 degrees is capable of transferring almost 50w into the air through the bucket. so realistically it should never defer from within a few degrees of ambient temperature unless you are using a dark container absorbing heat from a light source. That's not calculating in for heat loss through evaporation either, which is greater if you are running a bubbler.