Need some HVAC help.
We get water under the heat pump unit in the summer when running the AC. We have a condensate pump and it is working. The water is not from condensate overflow, but coming from under the unit itself. This happened last year as well, but only seemed to happen if I turned it off and opened the windows (increased inside humidity). This year it is a daily event to the extreme of having to use towels to soak up the water. Any suggestions?
1. plugged filters and or coil.
2. The condensate drain leaving the cabinet and going into the pump is not trapped.
Here is what happens. ...»
With the fan unit in the cabinet being the mid point between the suction side of the system, (return) and the pressure side of the system (supply air to rooms) the return side is under a slight negative pressure. While the supply side has a positive pressure when the fan is running.
When this happens the fan does what ever it can to pull air to it. If the filter is dirty, or return ducts are blocked , or the coil is dirty more suction is created in the return side. The result is that air is being drawn back up the condensate drain opening and not allowing water to properly drain back into the condensate pump. When the fan shuts off the water that has overflowed and was prevented to drain out spills out of what ever openings in the cabinet that exists. The result is leaking coming out all over the place. Once the fan turns back on this negetive pressure is then created and the air flow being pulled back into the cabinet is now preventing the water within the cabinet and interior condensate pan from dripping out.
If there is no trap on the condensate pipe leading to the condensate pump the air is pulled up the pipe while the system runs. This prevents water from properly draining out of system and the same leak occurs when the unit shuts off.
So check to see if you have a trap, much like the one you would see under a kitchen or bathroom sink. and or check to see if your filter is plugged or return grills are blocked by something.
A good way of telling if there is a lack of return air is to watch the return duct when the fan is turned on. If it appears to be pulled in due to suction inside of it, then I would question the duct size or possible blockage.
Bob
Air flow can be an issue as well, it can cause your system to not perform properly producing ...»
Example: If a homeowner puts a fish tank in their house, then your going to increase the humidity and therefore have more condensate going into the pan. If the pan is plugged or stuffed up then the condensate can't drain properly. Try putting an air hose into the condensate and blowing it out.
C.R. Draves