CPVC on Condensate Pump Drain

Hey Folks-

Hopefully I haven’t used up my question quota for the week…but I wanted to ask on this one as well. Usually on condensate pumps I always see the flexible plastic tubing. On this one they did connect flexible tubing directly but then quickly changed over to CPVC, even on the uphill climb. Is that something to be concerned about?



I don’t see why it would be a problem. I always include a note telling them a mechanical pump was in use, that they fail, and should be frequently monitored.

I didn’t get the manufacturer on this one but looked up the installation instructions on a standard condensate pump and it said:

“The outlet piping should be flexible tubing secured with a hose
clamp (not provided) or pipe (3/8 inch I.D. maximum to prevent
excessive flow back to unit).”

I would interpret the “or pipe” to include CPVC but wanted to double-check with you all. Thanks.


Was it larger than 3/8"?

Yep, I just found a pic that confirms it’s 1/2" pipe. Is that enough information to call it out? Or do I need to determine the exact manufacturer of the pump and check it’s installation instructions to see what it requires?


IMO it will not work, I would Write it up .No back check so it will run back

I would write up that bad chimney too.

If the unit has been there for a while and you saw no evidence of overflow, I’d just learn from this thread and move on. I doubt you’ll be sued over it. We’ll all know better next time we see it.

Where was it located?

Since no one asked yet ,check out the hood.

Bob - what the hey are you talking about??? I didn’t give you any pictures of the chimney or hood (though they were both bad!).

Hey Joe-

Furnace room is in the middle of the basement. Interestingly, they shot that thing up and then probably over a good 15’ and then brought it down into the washer drain. Problem though…the 1/2" drain line takes up enough space in the washer drain that the washer hose doesn’t fully fit in there.

So if you don’t call it out and if the unit fails in the basement, what type of damage would result?

Bob - what the hey are you talking about? :? I didn’t give you any pictures of the hood or chimney (but they were both bad!)

Looks like it fit to me. Not much room to spare, but it fit.

I didn’t see any open floor drains in the basement. Half the basement has recently been re-done…other half is crawlspace. I just sent out the report earlier today (client accesses online). I think I’ll update the report and email the client on the change. I feel it’s worth noting…even if I likely won’t get sued over it. I’d rather not take the chance :wink: .


this is how.

If the pipe is bigger than the manufacturer specifies for max size you should write it up as such. The larger pipe will certainly carry the water, but if the water in the pipe runs back down and refills the reservoir after the pump shuts off, the pump will cycle much more frequently, reducing its service life.

I agree Chuck, the problem was I didn’t get the manufacturer or model on that pump that was there. The instructions that I posted earlier was just some instructions from an average sized Little Giant condensate pump. I’ll know now that if I have a question, to be sure to grab the model number on the product. Even without it though, I felt I had enough information to indicate it potentially could be a problem and worth noted. There were several other plumbing/hvac issues so the technician is going to be there anyway.