Uphill from collection tank to RO

[pdr]

Help. Can the inlet pump on an Airablo RO pull sap up 18" or so from the outlet of the sap tank? If not, what kind of pump can I use? It's about a 30 ft run from the sap tank to the RO. Thanks.

[wiam]

My RO will pull sap up that far, but I hate to have the pumps run dry like that. I have my raw and permeate tanks higher than mine so they will gravity feed.

[pdr]

Wiam, the problem is I can't raise the bottom of the raw tank or lower the RO. So I've got to somehow pump the raw sap into the RO. The permeate tank is above the RO, so that's no problem. I'm not sure what you mean by the pumps running dry if the RO is pulling in the raw sap.

[Ecnerwal]

If there's no sap in the line when the pump starts, and the sap level is 18" below the pump, it's sucking air (running dry) until sap gets to it. Not good for many types of pump - simply doesn't work with others - fine with some others - and I have no idea what you actually have for a pump. If I ever get RO it will have to be the cheapest possible homebrew.

Now, if the outlet of the tank is 18" below the RO, do you have more than 18" of sap (above the outlet) in the tank before you start the RO? ie, would sap from the tank gravity feed that far at the start of the operation? If so, it's not running dry until it runs out at the end. That might work - hopefully someone who knows what you actually have will come along.

[wiam]

Wiam, the problem is I can't raise the bottom of the raw tank or lower the RO. So I've got to somehow pump the raw sap into the RO. The permeate tank is above the RO, so that's no problem. I'm not sure what you mean by the pumps running dry if the RO is pulling in the raw sap.

I have been told by several maple dealers not to set up your RO higher than your tank. Your other option is to pump sap to a higher tank.

[pdr]

Should be at least 35-40 inches in the raw tank before I start the RO, so filling the RO feed pipe shouldn't be a problem. Guess I'm wondering what will happen when the level in the tank drops below 18" - will the inlet pump in the RO continue to pull the sap in?

[oneoldsap]

You would be making an incorrect assumption ! Your setup is going to be a major PITA . The issue is getting the air out of the line , and the pump primed , BTDT !

[Maple Hobo]

Help. Can the inlet pump on an Airablo RO pull sap up 18" or so from the outlet of the sap tank? If not, what kind of pump can I use? It's about a 30 ft run from the sap tank to the RO. Thanks.

We had to install a feed tank, used a sump pump with a float in the feed tank to regulate it.
Then added a pop filter bag to the sump discharge pipe over the feed tank.
Works like a champ and keeps larger stuff out of the ROs filter better. Its easier to swap a pop bag instead of stopping or having the RO Auto Shutoff and changing the filter in it.