Blowing out the main drain


Active member
Aug 1, 2016
Ashland Ma
First time we have closed our pool ourselves and all was going well. We blew out the skimmers, returns and the main drain. Opened the inlet and outlet to the heater and blew then sucked to ensure we got everything. Somehow we opened the main drain and sucked some water out into the shop vac. We thought we could just blow it out again to get bubbles and create an air block. Ran the compressor for 10 minutes and still no bubbles. Trying to avoid calling in the pool company. Any suggestions?


Platinum Supporter
TFP Guide
Jul 30, 2014
Monmouth County, New Jersey
Please provide a little bit more detail about the main drain. I need to know how you did it, what type of compressor and where you hooked it up to. Also, the shut off valve selection makes a big difference. If you can isolate the main drain by itself and you have separate shut off valves for the skimmers, then you will be able to get to the main drain.

Recently I used an NPT fitting at my friends house for the main drain. However, the run was about 20-25 ft., and plumbing was 1.5". Went very well with an air compressor and about 25 psi. We need a little more information.