Why is there a rubber plug in the overflow drain

Problems related to residential installations.

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Why is there a rubber plug in the overflow drain

Post by HotInHuffman » Tue Dec 23, 2014 12:03 pm

I have 2 Rheem Air Handlers (RCTH A060S) in the attic and I noticed that the overflow drain of both air handlers has a rubber plug in it. I wonder what would happen if some day the primary condensate drain quits working? How would the condensate be removed from the air handler?

Is it normal to keep the overflow drain plugged? I called Rheem and after being shuttled around a few times, I got a ho-hum answer. I was told "it depends". Depends on what, I asked. More ho-hum from the Rheem customer service person.

Any intelligent explanation will be very much appreciated. Thanks,

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Joined: Wed Dec 24, 2014 7:53 pm

- Why is there a rubber plug in the overflow drain

Post by maxgreenairhvac » Thu Dec 25, 2014 2:47 pm

Overflow drain is caped because your HVAC contractor never wanted to protect your whole house from damage .
Imagine scenario you are away for a day, and your air conditioning running on thermostats cool mode schedule . Drain gets cluttered but air handler will still run, and the next day you will find your whole house in water. To avoid it every normal contractor should offer you extra protection which costs almost nothing, and you won't have to renovate the whole house.

1.Overflow drain connected to the drain pump with 3/4 PVC And pump With 3/8-1" plastic hose is connected to any drain in house or sink or just run it outside of the house .
You can also do it by your self . Everything you need is in Home Depot 20-30$ for PVC pipe , Get P- Trap Also ,
2.Small drain pump (same in home depot may be another $80-120 ) check voltage 110/220 and pick the right one.
3.You should get a sheet metal drain pan with 1" border , 2 inches bigger than your unit and put it under unit
Same with pump, you can put one pan under it too or you can just get pump so you know size of it after look on your unit and decide what side to increase to fit a drain pump into main unit pan if you can in case pump will go off one day or get separately small drain pan only for size of drain pump but if you do that you must get another water leak sensor if you increasing size and using only one big pan to fit unit size and drain pump u will eliminate second sensor
5. Water sensor to automatically shut off A/C (another $40-80 )
So all together for less then $300 you can avoid damage for thousands.

Imagine a different scenario

Main coil pan is getting full because of main drain line cluttered .
Now water will go to overflow drain line after to the pump and will start pumping it outside
if pump goes off , or overflows line will get cluttered also,
now water will go to secondary drain pan and sensor will shut off the system.
If pump go off, sensor will shut off whole system also

Now we got one of the best drain protection.
1.You should check drain pan level to be safe its at correct pitch down.
2.Clean your drain twice a year its only 50$ to blow it with nitrogen.
2.Clean drain pan because when water stays long in one place due to incorrect pitch, water makes dirt and clicks.

Hope you will understand.had no time for better explantation .

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- Why is there a rubber plug in the overflow drain

Post by Freon » Thu Dec 25, 2014 4:05 pm

Check to see if there's a float switch in the condensate pan. Many installers will have a float switch to shut off the entire AC system if the primary drain becomes clogged. If there's not a float switch, consider installing one... simple and inexpensive.

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