what causes a slant coil in an upflow installation to drip water on the filter below it when in an AC mode?
the drip is not from the condensate drain but from the face of the coil.
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Replies
Dirt.
Shine a light through the coil. Move it around. You may find a clean spot and see more light there than other spots.
Use a foaming spray type coil cleaner. They make a rinsless variety, but it doesn't hurt to spray a fine mist of water through the coil even when using a rinseless cleaner. Let the coil dry a few hours and repeat the light test. Repeat as needed to get the coil as clean as possible.
You will be surprised at how much more efficient your unit cools too. Next buy premium grade pleated filters and change them regularly.
Go outside and clean the condenser coil also. It needs more diligent attention than the evaporator coil ( there are no filters outside).
Dave
thanks.
I looked at it today with the filter off. Lots of drops of water just hanging in the mid coil area - they do not seem to run down the sloped coil into the condensate pan, but rather they drip onto the filter.
i sparayed glass cleaner on it - was afraid to use a coil cleaner for fear it might eat the joints - coil is about 15 tears old and cools great. outside cond is clean.
thanks
what brand coil cleaner do you use?
would weak vinegar solution work?
It does not need to be an acid type cleaner. A good household spray cleaner like 409 will work. You could also stop at a local HVAC supply house and get one of the rinseless foam cleaners in an airesol can. They work pretty well and are not suppose to leave any residue for future dirt to build up on. Spray both sides if you can get to them and blow it out with the exhaust from a shop vac. As I mentioned before, it may take a couple of times to get it clean enough to shine light through it. I sometimes blow them out before I use any cleaner on them. Saves a little time.
Good luck.
Dave
What about the possibility of the coil freezing up from low refrigerant or low airflow? When mine was low I had wet filter syndrome. Probably by the time I shut down and looked it was thawed.
I will check.
usually tho with a freeze up there is no air flow and no cooling. unit works well but I will check
Did you ever find a fix for this? I have the same issue.
It’s a flow coil and drips about 15-20 drops of water, every time the unit cycles on. However, when it comes to your air conditioner's drip pan, also known as the drain pan, the presence of water is perfectly normal… but only if it's flowing out of the pan. ... When not taken care of promptly, a clogged drainpipe can cause serious mechanical problems for your air conditioner.
Thanks for the reply. This is not a drain issue.
I have a Trane air conditioner model TWG030A140B1.
The air handler has a single evaporator coil mounted vertically at about a 45 degree slant.
As condensation build during normal use, the water will trickle down the fins and into the catch pan and the out the drain pipe.
Water drains great, no issue there.
The issue is that as some of the water trickles about half way down the fins it then drips straight off of the coil and onto the filter.
Eventually the water will pass thru the filter and collect on the floor.
I’ve cleaned the evaporator several times with a garden hose along with different store bought cleaners as well as dawn dish soap with a soft bristle brush.
Still have the same issue. Nothing works.
Fins are in great shape, nothing bent up. Nothing plugged up. I can shine a flashlight thru the coil.
Any suggestions?
Also, I found the attached bulletin on a different Trane manufactured unit that describes the same issue. I'm thinking about adding a gasket to seal mine better. Not sure if that will help or not.
A wet air filter commonly indicates a clogged condensate pan or condensate drain lines. ... When something prevents this water from draining away, it overflows and the air filter may absorb that moisture. Another possible cause is moisture that may be falling directly onto the filter from the evaporator coils.
I have a brand new Rheem slant coil A/C handler and heat pump. After 1 day the filter was getting wet in various spots up high. The firm that installed it came out and slowed the fan one notch as it was sucking the filter into the condensate coil. I also made a 1/8x20x25 cardboard spacer almost identical to the aero filter cardboard side and placed that between the filter and the coils. Still gets a good seal. Will let that run for a bit and see how it does. If it works well I will make one out of plexiglass and put the 3M Merv13's in the aero's place. It's not the condensate drain - it's just the filter is too close. We are in Florida and the A/C runs quite a bit. You can also up the temperature on the thermostat so it doesn't run as much and create as much condensation.
Wet filter and spacer
please tell us the solution when you get it.
if you post the question on one of the big havc forums they will tell you to call an HVAC pro as this is dangerous work, you can spray the coil cleaner into your eye or cut yourself on the coil.
Ran it for a few hours. Filter stayed dry. Cardboard had a few minor wet marks. Now to get a piece of 1/8 inch x20x25 piece of plexiglass or plastic, cut some holes in it to match the aerostar filter and replace the cardboard.
Found something else that might work. I could use this filter as-is or take the grid out and put between the paper filter and coils. $23 at Lowe's or probably Amazon. Saw it and thought it would save msking my own spacer.
Have had same issue out of a Nordyne system past 2 years. 2 companies came out said could be a line blockage, so that was cleared and recharged.
When it happened again not sure if same issue but tech came out, recharged... I then noticed condensation was building on the bottom of the blower motor housing which stumped the tech. They cleaned the coils and AC season was over. Now it's here again and I think the problem is as well.
The one company thought maybe the fan motor was on its way out, the system is only 5 yrs old. Ran great for the first 4 yrs then I came home to a pooling of water coming out of the hvac closet. It didn't return all the summer until I went to change the filter and there was a fair amount of water that was trapped on the filter, but hadn't made its way onto the floor like before.
No idea what is going on. Same 45 degree slant coil, but the water is coming from above dripping on it and passing right through.
It is NOT a drain line issue or drain pan, the pump motor works and has been pumping normal condensate outside. But, the condensation that is forming on underside of the blower motor housing is what is dripping on coil then passing thru and onto filter. Why would condensate build on the fan housing? The unit is sealed well as far as I can tell.
No tech here but increasing your fan speed probably isn't going to help with it dripping out the backside and not draining. Also if you got room try leaning the unit to the left a lil to increase the angle of the evaporator coil. Also make sure the unit wasn't designed for a fresh air intake, if someone blocked it off it will increase the pressure across the coil and screw with the draining, if it does you could install a adjustable coil bypass damper into the cover plate and adjust it till the dripping resolves itself.
Decreasing not increasing helped because it doesn't pull the filter as close to the coils with less suction. No more wet filters. Happy camper.
My filter is well below my coil, 4" style filter in it's own box area. The coil is a 45* slant creating an A-frame