sarahw_tx....actually it the other way around, the one sweating is for the downstairs and the other is upstairs. I did get up in the attic this morning and noticed the sweating is pretty non-existent (just a little moisture). I am beginning to think that the humidity and heat of the day caused a lot of it, but overnight it cooled down in the attic therefore changing the "chemistry" up there. We shall see today. I think I will add some insulation today and see how it goes. If anyone has any other thoughts please keep 'em coming. Thanks.

lazypup, I'm glad to see you still here on this forum! I saw your post about the ads and thought you were gone for sure. Thank you for responding. Just to clarify my original post just a little bit more: all my condensate from the furnace drains into a pump with it's own reservoire. When the reservoire hits a certain treshold the pump kicks in and dump 50% of it's contents through a piece of clear flexible tubing. What I want to do is to run this pump discharge into a set of fittings to convert it up to 2" PVC. Afterwards it would run into a 2" P-trap (per lazypup's suggestion) and after this into the main 3" drain. I picked 2" because I currently have an unused 2" Tee into the main that I was going to cap since I don't have a use for it. The only thing I'm wondering is if a condesate pump has enough pressure to push out all the water in a 2" trap? I'm thinking that couldn't happen.... What do you think about this layout? Would the pump discharge need some kind of vent? If the line goes straight to a p-trap, is the pressure problems that I should be concerned about? Thanks, Shade

The preferred method is to run the line through the wall and discharge outside the structure. When discharging outside the structure the point of discharge must be at a clearly visible location and may not be obstructed by shrubbery or landscaping materials. When discharging outdoors the discharge end of the pipe MUST BE pointed downward. Under the International Residential Code the point of discharge must be within 6" of the average terrain ground level. Under the Uniform Plumbing Code the point of discharge must be greater than 6" but not more than 24" above average terrain. In a garage or unfinished basement the T&P line may discharge on the floor providing the said floor is equipped with a floor drain. When discharging on a floor the T&P line must extend from the output port of the valve to within 6" of the floor surface and the end of the line must direct the flow downward. When a gas water heater is installed in a basement where a T&P gravity flow drain line cannot be achieved the standard Temperature & Pressure Relief Valve (T&P) valve is to be removed and a WATTS 210 gas shutoff valve installed on the water heater vessel. A Pressure Relief valve is then installed on a hot water line at any convenient point above grade and a discharge line extended outdoors or to an approved indirect waste receptor. The T&P valve may be discharged into the house DWV system providing it is connected by means of an approved "indirect waste receptor" such as a utility sink or floor drain providing the lowest point of the discharge line must remain a minimum of 4 times the discharge line diameter or 2", whichever is greater, above the flood level rim of the receptor. A T&P discharge line SHALL NOT discharge into a water heater drip pan. The T&P discharge line diameter must be equal to or greater than the diameter of the discharge port. If the total developed length of the T&P discharge line exceeds 40 feet, the line size must be increased by one nominal trade size. All horizontal runs of the discharge line must be pitched at 1/4" per foot towards the discharge end. There shall be no traps or valves on the discharge line and the discharge end of the line SHALL NOT be threaded. (If run with galvanized iron pipe the threads must be cut off the end of the line).

Not all AC systems need a trap configuration like this as Mike shows, for the simple reason they have a trap already. It is never a good idea to have two traps on one drain. In some cases the trap is hidden, depending on the age of the home, local codes at the time it was built, etc. WHY? Double trapping creates an air-lock between the two traps thus impeding flow and not permitting proper air flow in the drainage system. Think: suction as the impeding force. In other words you 'may' create a situation that actually clogs your drain more than it otherwise would and if your E-coil does not drain properly the condensate water is known to otherwise be the determining factor in causing refrigerant leaks. If your E-coil does not drain properly it is sitting in condensate waste water that contains chemicals (VOC's) that have leeched from the structure furnishings etc. Nearly all Freon leaks that develop in the E-coil start in the base of the coil that is typically more exposed to condensate waste water.