Trane Tam7 Hyperion AHU leaking condensate
My Trane TAM7A0C36H31SAA AHU manufactured in October 2011 and installed as part of a matched system with a 2.5 ton Trane XL15i Heat Pump last November is leaking condensate. The water is leaking both through the seam in the modular AHU unit and through the door. I opened the coil section door to check for any blockage of the drain and found that the water is dripping from the plastic diverter which is installed at the apex of the A coil and splashing the door running down the inside of the door and leaking out the door gasket. Some of the water is also splashing down into the recessed portion of the bottom of the AHU where the fastener ties the two pieces of the modular AHU together and leaking out through the bottom seam in the AHU. There is a particular spot on the plastic diverter several inches back as viewed through the door opening where the water is dripping from. A video showing where the water is dripping off the diverter is at http://youtu.be/c-woIbEd5Zg . I am sorry about how shakey the video is. The unit is installed in a horizontal configuration and is level and the diverter appears to be properly installed. Fortunately the way the unit is installed the electronics are on top or else the board would have gotten soaked. The system is under full 10 year P&L warranty from Trane through my installing contractor and I have a preventive mantanence agreement with the installing contractor. Fortunately the AHU is installed in a crawlspace so the water is not going to dammage anything immediately though it is going to make my SantaFe Compact Dehu work overtime untill this issue is resolved. As we are in a record heat wave here in VA and the system is cooling well I have not yet contacted my contractor as I'm sure they're probably swamped with no cooling calls. I just figured check on here and see if anyone has seen this problem with the new Trane Hyperion AHU and what suggestions the experts here might have. I have been a longtime reader of this forum and appreciate your thoughts on this issue.
Time to get the installer back
I definitely plan to get my contractor back to look at my leaking unit. I was mainly interested to see if any of the pros here have seen this type of problem with the new trane AHU's as it seems like the design of the AHU having a recessed area under the diverter with the fastener which ties the two parts of the modular ahu together might be a common leak location & possible design flaw.
Thanks for your thougts on this.
I haven't had one leak like that, it seems odd that there would be that much water dripping off the coil, especially at the apex of it.
Do you have a picture from a little bit wider angle, showing the whole coil, especially the apex of the coil?
There is a screw that comes in the parts bag for the unit that has to be installed to keep the apex of the coil from sagging down a little when the unit is installed in a horizontal application.
If the screw is missing, the apex of the coil could be dropped down a bit, causing water to drip off that may otherwise run down the face of the coil.
That's an odd one. Could be that screw that Mark is talking about. Is the dehumidifier tied into the supply and return of the air handler? Maybe the DH is blowing water towards the apex during when the AC is cycled off.
Originally Posted by k-fridge
Thank you for your replies.
The coil securing screw near the apex of the coil is in place.
Unfortunately I don't have a wider picture of the whole coil. It did not appear that the apex was sagging but I guess it would be hard to tell if it is slightly off. I did check that the whole AHU is level.
It appeared that water was running off the coil on to the plastic diverter where it is clipped on and where it is making direct contact or near direct contact with the coil. The diverter appeared to be clipped on properly.
The unit had not been leaking condensate untill yesterday. I have been using the unit in cooling since warmer weather began this spring. We have had quite a heat wave with high humidity recently. I had been out of the house for 12 days on vacation untill Thursday and I had left the thermostat set to keep the house at 80 untill I got back Thursday when it brought the temp back to 70 with the "vacation" mode of the TCONT 802. When I'm home I keep the tstat at 70 and the system cycles keeping the humidity at around 43%.
The really weird thing is the unit has not leaked any more condensate since I put the blower door back on and powered the system back up yesterday. The only thing I did while I had the door off was put my hand on the plastic diverter to verify it was clipped into place which it seemed to be. It has been running with fairly long run times today because the temperature here got up to 102 and the system has been set at 70 but it does cycle off once or twice an hour even at these temps so I guess it is likely oversized though it's always maintained about 43% humidity. My old Goodman of the same tonnage would run almost 24/7 in these same conditions.
My SantaFe Compact dehu is not tied into the house HVAC system it is just dehumidifying the crawlspace as I have sealed the vents and placed vapor barrior on the floor. The walk in crawl space stays at around 43% humidity.
Thank you once again for your thoughts on this. I guess I'll keep an eye on it and if/when it starts leaking again I'll call my contractor to look at it while it is leaking.
Well my AHU is leaking condensate again today. It had not leaked since Saturday which is weird.
I shot another video with a wider view of the coil today.
I will be contacting my contractor.
Any other thoughs on what might be causing this? It looks like the plastic air diverter is in physical contact with the coil on both the top and bottom. I did not see any ice or frost on the coil and I have never noticed any frost on the suction line. It has now done this with outside temps of over 100 F and with temps in the low 80s F indoor temps of about 70. The system is usually getting about a 20-22 degree F delta T taken at return and supply nearest the AHU.
I guess I'm the lucky first person to have a condensate leaky Hyperion or are there a bunch of these in attics dripping into secondary pans?
Thanks again for your thoughts.
Did you ever get this issue resolved?
I put a TAM7 air handler in today, first one I've had my hands on since you started this thread, and had a close look at the air diverter.
When it is properly installed, it does NOT make direct contact with the cooling coil, there is a very uniform 1/4" gap between it and the face of the coil.
If it is making contact, or very near contact, with the coil, it would tend to wick condensate off the coil so it drips in the wrong place.
Thanks for your reply.
On the 13th I took one more look into the unit myself before I had planned to call my contractor on Monday morning to have them look at it and I discovered that some insects were on the coil in the crevace where the top of the lower coil begins behind the apex just behind the plastic air diverter and the drips of condensate were comming from the diverter just below where the insects were sitting on the coil. I was pretty disgusted to go online and find that these insects appeared to be "waterbugs" or giant cocroaches. I keep the house clean and have never seen a roach in the house but I looked around in the crawlspace and found a couple of these things on the plastic vapor barrier near the crawl space door. I guess they were comming in around the crawl space door to get out of the heat and found a water source on the AHU coil. I went to Lowes and got a bunch of bait traps and some gel bait and put it in various places in the crawl space and within a day the AHU stopped dripping water and I have not seen any more so far. I hope it is not just a coincidence that the AHU has not dripped any more since I have hopefully eradicated these bugs but the water was dripping off the coil precicely below where these bugs were sitting. I suspect that the bugs were breaking the surface tension of the water droplets on the coil causing the water to drip off rather than run down the coil.
If it starts dripping again and no bugs are present I'll call my installer.
The air diverter on my coil seems to be touching the coil. I'm pretty sure it must have came from Trane that way as the installers did not have to dissassemble and reassemble the modular AHU for my install.
Has anyone else seen insects attracted to condensate in AHU's before?
If my unit were installed with the blower door on the other side the control board would have been on the bottom side of the unit and would have been soaked by this condensate. I guess if given the choice it would always be best to orient these AHU's so that the control board will be on the top if mounted horizontally otherwise the might get soaked at some point.
Those "water bugs" are common in my part of the world.
They can come into the house through the sewer too.