I figured out that if I jumped the presure switch the heater would come on so I ordered a new switch. The new switch also doesn't close the circuit. So I pointed the siphon tube in a direction I didn't mind getting wet and turned on my pump with the switch off and nothing came out.

I haven't changed anything since I winterized it. I'm assuming the tube is blocked with a bit of dirt or rust or something. I stuffed about 18 inches of weedeater filament into the tube but it couldn't get it to go the last 6 inches, think that is because of a tight bend, but it could be the blockage. Either way I didn't get any water to come out.

I have to go buy a special wrench to remove the other end of the tube without tearing the heater apart and try to clear it. Anything else I should try or buy?

We're having a pool party next Friday so i need to have it running by Wednesday night.

The switch and tube and 18 and 19 on this diagram: http://www.poolpartsonline.com/popup.aspx?src=wolthuis.aspx%3fproductid%3d325%26size%3dlarge

With all the twists and turns in that tube it's no winder you couldn't get the trimmer line through it. I think you have a good plan. Take the tube loose and see if it's blocked. Then go from there.