Pumping black tank

[ghanesdvm]

There could be circumstances in which I might "live" in my AS while parked at home, or have a long term guest. It would be ideal if I could empty my AS black tank into my home septic tank. The problem is that the AS sits about 15-20 feet below grade of the septic tank cover. I was considering installing an external macerator pump to the black tank drain, but I can't find manufacture's specifications on how uphill these 12v units will push a column of water. From what I have read, 2.31 ft column of water creates 1 psi of pressure. So it looks like the pump would need to generate around 8 psi. Not that much.

Does anyone have insight to this situation or better math than me?

Gary

[BayouBiker]

I found a spec sheet for the Jabsco pump it shows 7.5 GPM at 20ft of head. https://www.fondriest.com/pdf/Jabsco...ers_Manual.pdf Looks like it will deadhead at about 23 ft. You will need about 3-5 feet over your actual to account for friction unless you go with an oversized pipe (2 or more inches). This pump will work if your elevation is less than 18 feet.

If the water level in your septic tank is significantly below the elevation of the cover, can gain that elevation difference back by stuffing the pipe down to waste water elevation and adding a check valve.

[Jim Flower]

I have one of these that I use in a pinch. https://www.google.ca/search?q=flowj...&client=safari
There are all kinds to choose from and some seem to be more suited for tougher performance. Jim