AC Condensate into sanitary sewer

[MOSSMANPE]

Lee County Florida prohibits condensate disposal into the sanitary system. I so far am at a loss as to why. Is it because of micro's in the condensate or what. I know of no other AHJ that stipulates this. Looking for feedback.

 

[stevenw]

The city has to pay to treat water in the sanitary system.

 

[MOSSMANPE]

And your point is???

 

[stevenw]

The more water you add to the sanitary system the more chemicals($) the city has to add to the sanitary to treat the water.
If the condensate goes to storm the city does not have to deal with it.

 

[MedicineEng]

I don't buy that explanation. Condensate in A/C are, as far as I know, pretty clean water when compared with sanitary water. In fact if you divert condensate into the sanitary water you have a dilution effect. As many polution level measures are in units/lt, in fact you should need less chemicals and treatment, as you are putting cleaner water in the line.
Why don't you inquiry the County directly? Eventually this is one of those regulations that is forgotten and nobody knows exactly the reason...

 

[MintJulep]

Possibly to prevent the back-up of black water into the air system, although it would seem an air-gap and/or backflow preventer would do just a well.

Steve's conjecture makes sense to me. It's not only about treatment and chemicals. The treatment plant needs to deal with every gallon of waste that comes in. Pumping costs are not affected by concentration. Makes sense to not deal with clean water.

 

[PEDARRIN2]

In some jurisdictions, the condensate has to go to the sanitary - although I have heard of sending condensate from roof top units to the storm via the roof drains.

And waste water treatment plants are concerned with volume. It is not just the pumping, but the concentration of the waste is important as well. It is difficult for the bacteria and other organisms to break down the sewage if the concentrations are too low.

This is one reason why the use of combined sewer systems (sanitary and storm) is not in vogue at present - too much water, not enough sewage.

But all this may not be applicable - depends on how much flow is coming from the condensate. In applications that I have dealt with, there was not enough flow from condensate to warrant not sending it to the sanitary. There might be another reason.

The best solution is to call the code official and find out why this requirement is in place.

 

[MOSSMANPE]

Ask the AHJ? It differs from county to county. Logic seems to be lost. Authorities pay more attention to verbage than logic - it's rediculous and sad. And you can't question these people - I mean gods. This is the same county that prohibited a fart fan from discharging into a parking deck. I knew one county that did not allow condensate to go to the roof drain. Total flow volume could be an issue, especially here in SWF where infrastructure is so far behind. Amazing there is that Collier County (Naples) has the worst problem, but they do not prohibite condensate in the sanitary sewer. I was thinking that maybe microbials were an issue, but nobody has a comment. So, this is still a mystery. Thanks for your input(s).

 

[RossABQ]

It also depends on whether you are talking about a DX unit or a chilled water unit. There could be chemically treated chilled water going to sanitary if a coil starts leaking. If there is an process waste system available, that's where we take these drains. It is an issue with glycol CHW systems especially. I suspect part of the issue may be that most inspectors can't tell whether an AHU is CHW or DX.

 

[BronYrAur]

Most inspectors wouldn't know an AHU if one fell on them. I can't add much to this other than I have seen areas in Northern IL where condensate must go into the sanitary. I think the reasoning was so that chemicals used to clean the coils would go into the sewer and not in the storm drain.

 

[Keith53]

Here is what the EPA has to say about it:

http://www.epa.sa.gov.au/pdfs/guide_aircon.pdf

BUT, your local code may differ.

IF you run condensate to sewer, then do it via 'wet' traps..."Wet" traps are traps that see routine use such as that found on sinks, laundry or baths.

The reason you want to use a wet trap is that when shut down off season, condensate traps evaporate dry and allow sewer gas to travel into ventilation system.