TOPIC: What the bend?

Why is this pipe bent?

It is a trap for the condensate line. It is a better practice to have a clean out as well.

I use these iillustrations at times.

That makes sense.  That was one of my thought but when I saw it was glued in on both ends I was wondering how it would be cleaned.  Your picture w/ the clean out is good.  So how would it get cleaned w/out a clean out....I guess it wouldn't?

Why is this pipe bent?

Your photo is of a “running-trap” for the condensate drain line from an indoor coil. A running trap's seal is too shallow, and can be sucked/blown dry during cooling cycle startups. i.e. running traps are prone to fail. Generally, manufacturers do not allow running traps. I comment on this fact, and recommend replacement with a proper trap with a cleanout plug installed. My preferred trap is the E-Z Trap brand (see attached photo).

The photo you attached is of a “blow-through” system (where the fan is upstream of the coil). In this case, a condensate trap is not critical—HVAC techs did not normally install them in blow-through coils. Recently, standards have changed, as they are installing condensate traps in all cases.

I insert the following one or two comments in the body of my reports (as needed):

"ATTENTION ITEM: Keep condensate line and trap cleaned during the cooling season. Before the start, and during each cooling (summer) season—it is important to open the pullout cleaning plug and monitor the condensate trap to insure it is clear of sludge and algae buildup for proper draining to occur. Consider keeping a bottle-brush handy for this purpose. In addition, pouring a small amount of bleach in the trap, at the start of the season, will keep it clear of bacteria and algae."

"Consider replacing PVC trap with a newer "EZ Trap" brand clear condensate trap. This type is easier to keep clean, with a see-though trap, and comes with an attached cleanout brush.  Ask your HVAC contractor to supply one."

BTW: Condensate drain-line trapping is a major issue in heat pump air handlers, or any “draw-through” coil system (where the fan is downstream of the coil).

Please refer to the Kenny Hart article published in the ASHI® Reporter, April 2009

http://www.ashireporter.org/articles/articles.aspx?id=1648