vakzo
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DIY recirculating aspirator issues
Because I don't have access to a faucet in my lab, I attempted to build a device which recirculates water through an aspirator. It's bein run using an
Everbilt 3/4 hp shallow well jet pump. The pump runs fine and generates a vacuum, but randomly shuts off after a small amount of time. The correct
voltage is being supplied (and tests correctly where it is connected to the pump) and it doesn't seem to be a cut-in/cut-off issue as it happens
randomly and the pressure reading was within the range the entire time. Anyone have any idea what could be causing this?
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macckone
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Obvious answers are overheating or bad pump.
Mine runs continuously with near max head pressure and no issues.
I have had the water get almost boiling and still runs.
I use a fountain pump with 15 ft head and 100 gpm.
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vakzo
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Do you know what specific brand/model yours is? I might end up just getting a new pump then.
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protem
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If you are looking at a new pump
http://topsflo.en.made-in-china.com/product/KMSxsZBopvpc/Chi...
I tried this and it works. It is a DC pump so a power source is required. The pump draws about an amp at 24 V. Very low heating effect - much better
than a jet pump. Good vacuum. Bought one through aliexpress.
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Sparklehorse
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Does your pump have any adjustments on it? I have a shurflo pump in a similar set up and I had a similar issue until I adjusted the screw that sets
the back pressure at which the pump shuts off. Before I did that the pump would cycle on/off repeatedly with the aspiration connected
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chemrox
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I bought Cole-Palmer aspirator pump for $40 and it's been honking along for ten years. It has dual aspirators and pulls <10 torr. It gets better
when ice is added to the reservoir. If you're intent on building one look into running parallel aspirators. As others said your pump is probably the
issue. A well pump is probably too high a volume and may not work with almost zero head of water. Also without running water how do you serve
condensers? Another pump? Volatiles should be purged from your system. I run my rotovap condenser through my aspirator reservoir. That purges the
volatiles.
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
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vakzo
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Quote: Originally posted by Sparklehorse  | | Does your pump have any adjustments on it? I have a shurflo pump in a similar set up and I had a similar issue until I adjusted the screw that sets
the back pressure at which the pump shuts off. Before I did that the pump would cycle on/off repeatedly with the aspiration connected
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Yes but after a couple hours of adjusting the cut off to different levels there was still no improvement.
| Quote: Originally posted by chemrox | | I bought Cole-Palmer aspirator pump for $40 and it's been honking along for ten years. It has dual aspirators and pulls <10 torr. It gets better
when ice is added to the reservoir. If you're intent on building one look into running parallel aspirators. As others said your pump is probably the
issue. A well pump is probably too high a volume and may not work with almost zero head of water. Also without running water how do you serve
condensers? Another pump? Volatiles should be purged from your system. I run my rotovap condenser through my aspirator reservoir. That purges the
volatiles. |
I apologize for not elaborating. I have a water source, but it is a garden hose with low water pressure. I have a drainage out and a constant stream
of water from the hose in to purge everything. Also what specific Cole-Palmer pump are you referring to as all the ones I seem to be finding are at
least $150 used?
[Edited on 13-4-2016 by vakzo]
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