Keeping AC P-trap clean with a Jones valve?

Question

We recently had a new AC system installed. It's working great. When it was installed, the company showed me how they installed a Supco Jones Valve for cleanouts if ever necessary, and explained that vinegar should actually be added after the p-trap so that nothing flows back into the HVAC unit. Seemed reasonable enough.

I went to do my monthly "add vinegar to keep the line clean" routine for the first time, and it occurred to me that now vinegar will never make its way into the p-trap, which seems like an important place to maintain since water will always settle there.

Any thoughts? I'm not a fan of blowing out the AC lines, and it seems like the new setup encourages that as the primary way of keeping the p-trap clear. I'm going to ask the company about this after the holiday weekend, but was curious what others thought of the setup. Here's an updated pic - my angle doesn't show the p-trap well.

Answer 1

The set up you show is very good and should serve you well.

I'm not sure what you are calling a P-Trap? The float switch, (part with a wire) is not a trap.

The drain lines usually don't have any traps until the outside termination, where a trap is usually there to keep bugs and lizards (Southern US) from getting in the line.

BLowing the line out is the common way of clearing the pipe. It's been done that way by HVAC techs for decades. There is nothing to worry about , especially since they put in the Jones valve.

As for monthly maintenance, it is often recommended, rarely performed. The most common time frame in my area is every 90 days. However that is more of a personal convenience thing than professional recommendation. In Florida during the hot months (April through November) Putting some bleach or Vinegar in the lines keeps the mold, mildew and general gunk from forming in the line and blocking it.

Why do you not need the vinegar in the "trap" or switch and closer to the air-handler is because the condensation there is colder and less likely to grow the organisms that block the line.