Remote resevoir topoff questions

[doughpat]

My RO-water resevoir is about 25 feet from the sump. I'd like to hook up my auto topoff unit (from autotopoff.com, double sensor with 50' wire leads) to a pump which will push water up about 8 feet (into the ceiling), then over 25 (or so) feet, then down a wall and into the sump. I'd like to use as small of tube as possible, for ease of routing and low cost (ideally 1/4" polyethylene, as I have a bunch laying around).

Some questions:
What is a good pump for this application? I was thinking about a dosing pump, as it would replenish water slowly, thus avoiding frequent on/off cycling. But it needs to be able to initially overcome some significant head/friction in the tube.

Also, there may be a siphoning issue, as the resevoir will (when full) have a higher water level than the sump. A simple siphon break should fix this problem--my question is where to drill the hole. I assume just above the intended water level in the sump?

Also, how to shut off the RO/DI unit. Would a simple ($15) float valve installed in the barrel do the trick? I don't mind wasting some water when the barrel fills up (it really should just be for those "oops, left the water on..." occurences), and i'd like to avoid spending the money on a solenoid-shut off system.

Thanks for any ideas.

 

[bleedingthought]

This might be perfect for you but it is a bit pricey:
http://www.marinedepot.com/md_viewItem. ... uct=AQ4511

HTH

 

[doughpat]

Thanks. I was thinking maybe the Mag 7 for a cheaper alternative. How do persistaltic pumps deal with head pressure?

 

[Len]

Peristaltic pumps are perfect. They do fine with long runs (head pressure up to 100 feet, but usually 25-50' is safe). They add water slowly as you mentioned, and they can run dry with no issue. Plus, they are A LOT more efficient then a big conventional pump. I love my Liter Meter III, but the Aquamedic will do the job for you too, and for far less (since you don't need the fancier features on the LM3).

 

[doughpat]

Good point--I'm sure the pump will run dry from time to time. I seem to remember a really inexpensive peristaltic pump...

 

[bleedingthought]

A mag7 would be way too strong for that, I think. Maybe a mag3 might work. But you would probably still get short bursts of water.

Like Len said, if you want a pump that can overcome head pressure and still deliver a small quantity of water then go with a peristaltic pump.