Last year we had a guy install a convertible jet pump configured for shallow well operation. He left no manual and I found that I couldn't prime it this year. I borrowed a manual for a similar pump and found that I needed to open the control valve to get prime. It didn't say if I should close it after. My take on the control valve is that it is used for the twin pipe deep well configuration and that I should leave it open for the single pipe shallow well setup we have.

Am I right on that?