Next time, please start your own thread regarding the Hi-Jacking.
Gary:
The previous owners left the 16 gallon shop vac they used to blow out the lines so I will try that first.
Contact the previous owner and find out what he did. That simple, especially with the 16 gallon shop vac.
I do have a 3 hp compressor with 60 gallon tank that I can wheel over to the filter and use. Looking at the strainer assembly there are 2 drain plugs that appear to be 1/4npt. My thought was if I plugged in the air line to that port the air will flow into the filter and the opposite direction to the skimmer or main drain inlet lines.
You can actually close the Multi-port valve off and no air will travel that way or you can use a rubber expandable plug (like I use) to close off the return side in the pump housing basket.
There is a multi position ball valve at the junction of the skimmer and main drain inlet lines to the skimmer. My system doesn't have separate ball valves for the skimmer or main drain. The return line from the filter to the pool must split under the pool somewhere to the (2) return eyeballs.
Speaking of the main drain is there any way to blow it out and seal it? Without a ball valve on the main drain line how to hold an air pocket in it and how long will that last?
This is the easy part. Close off the main drain. Take your shop vac and suck the water out of the skimmers first. Then go back and blow the remaining water out which should be very easy (This is what I do) and as the compressor is blowing all the water out of the skimmers (you can even close one at a time) to help out, use your shop vac and keep sucking any water out. Then shut off both units for now. Now install the first Gizmo. Go to the other skimmer and remove the Gizmo and start blowing air through that one while sucking up the water. When done shut everything down again. Install the next Gizmo.
Now go back to the pump housing and open the main drain. Blow air in the main drain until the water bubbles at the surface for 45 seconds to 1 minute (depending on how powerful the blower is) and quickly close the valve at the main drain and you will hear the "air lock". Open the basket and add a rubber plug to the suction side so if the valve fails you have added protection.
Winterize your filter:
Winterizing your Sand Filter (same as other sand filters with multi-port)
Interesting to note: Hayward Manual for the S244T 24" 300# sand filter, states only this in their instructions for winterizing:
WINTERIZING
1. Completely drain tank by unscrewing drain cap at base of filter tank. Leave cap off during winter.
2. Depress Vari-Flo control valve handle and rotate so as to set pointer on valve top between any two positions. This will allow water to drain from the valve. Leave valve in this "inactive" position.
winterizing with a sand filter
I am actually going to start a new thread explaining each step (in detail) so each post can be linked. Pool closings are very easy if you have the right blower, plugs and shut off valves for skimmers, main drains and returns.
Please keep us posted!