Originally Posted By: rray This post was automatically imported from our archived forum.
If I don’t find drain pans in attic horizontal furnace installations, then I recommend having one installed, along with secondary drain lines and a float switch. I never find drain pans with vertical installations, regardless of where the vertical furnace is located? Why?
Originally Posted By: Blaine Wiley This post was automatically imported from our archived forum.
I have always found drain pans under vertical and horizontal furnaces located in the attic, and vertical furnaces on the second level of the home Around here, I even see drain pans below the suspended horizontal furnaces in the garages.
Maybe there is a shortage of galvanized sheet metal in California
Originally Posted By: rray This post was automatically imported from our archived forum.
There may be a shortage here because you’re using all of it there?
We have about 60/40 horizontal/vertical installations, and the drain pans just are not there for the vertical furnaces. Gut instinct tells me I would like to see it, but I thought maybe there was a valid reason for it not being there.
Since I never find them, if someone can post a good quality picture that I can use, it would be helpful. Thanks.
Originally Posted By: gsutterfield This post was automatically imported from our archived forum.
Russel
I've seen a lot of horizontal units without an internal drain pan but all the vertical units have had the internal pan . This might account for not having an external pan on the vertical units.
Originally Posted By: rray This post was automatically imported from our archived forum.
Anyone have a picture of an internal drain pan? Virtually all my vertical furnaces have the filter laying down inside the furnace, so unless I just don’t understand what the internal drain pan is, I’m stumped.
Originally Posted By: gsutterfield This post was automatically imported from our archived forum.
Russel
Let me try again as I don't know if I understand what I was saying 
The horizontal unit has an internal pan under the evap coil only . Any moisture carry over outside of this space will leak to the outside of units housing thus the need for an external pan . The vertical unit also has an internal pan under the evap coil but since it is vertical any moisture carry over is directed upward and will then fall back to the internal pan below.
Sorry I don't have a picture .
IMHO , I would always recommended an external condensate drain pan for a unit above any living space as an extra precaution.
Originally Posted By: Blaine Wiley This post was automatically imported from our archived forum.
Man, Now I am confused. Every condensate pan I have ever seen on the inside of an air handler or furnace is located below the evaporator coil, whether the unit was manufactured for horizontal or vertical installation. The external drain pan is something that (in the counties I have worked in) was required under any furnace or air handler with an evaporator coil to prevent water dripping through the attic floor or second floor in the event of a blockage in the primary condensate drain. The external drain pan also has to have a drain line and a safety shutoff switch. A clogged condensate drain line will cause the furnace/air handler to overflow in either installation.
Originally Posted By: rray This post was automatically imported from our archived forum.
Horizontal furnace looks good. Now come on, guys. Let’s get some action on this vertical thing that is located in an interior utility closet. Exterior drain pan or not? Sometimes? All the time? Never?
Originally Posted By: rsummers This post was automatically imported from our archived forum.
All coils that come in a case that I’ve ever seen have had drain pans. Some coils are sold multi positional and some have can only be used in the horizontal or vertical positions. Some of the larger horizontal coils have a splash guard at the end that keeps the water from blowing out of the coil. All units that hang or stand over finished space should have secondary pans underneath. I’m just waiting for the 90% furnaces that have the coils on the exhausts to start failing. Its going to start happening at some point then they may require there to be a pan under the whole unit like they require under fan coils.
Originally Posted By: rsummers This post was automatically imported from our archived forum.
Russel when I install furnaces or fan coils in closets that are in the attic or in a 2nd floor closet I install pans underneath but not on the 1st floor or the garage. I know of a group of homes that were built 20 years ago in this area that were put in upstairs closets with no pans and they have had problems with the pans rusting out and damaging the ceiling bellow. I don’t think that the inspectors in this area that do code enforcement for the city would call it if it was in a closet. In this area the pan under the unit has to be ran with the secondary on the main pan and terminate over a window or door.
Originally Posted By: jpeck This post was automatically imported from our archived forum.
While the IRC is written differently than the Florida Building Code, it does end at the same intent. A drain pan is required under ALL evaporator coils.
There should be a primary condensate drain line from the primary condensate pan connection (the lower of the two openings which are side-by-side) and there should be a secondary drain line from the secondary condensate connection (the higher opening right next to the primary condensate opening). The secondary drain line should run to the secondary drain pan under the furnace or air handler which has the evaporator coil.
The secondary drain pan should then either be drained (the preferred method) to the exterior with the discharge in a conspicuous place to warn the occupant that the secondary drain pan is in use (which indicates that the primary drain is clogged), or, install a safety cut-off switch in the secondary drain pan to cut the system off when water begins to collect in the secondary drain pan. This way, when the a/c technician comes out to find out why the a/c is not working, they see water in the secondary drain pan and know what the problem is. And the water does not overflow and ruin the ceiling - the reason for all of this.
Originally Posted By: gsutterfield This post was automatically imported from our archived forum.
Russel
As previously stated , I would suggest a secondary drain pan be installed under any unit mounted above a living space . Unless this unit does not contain an evaporator or other moisture producing items .On most verticle units , this is only a precautionary measure should the interior pan drain lines become clogged .In any case, I also suggest in my reports that preventive measures should be developed so as to insure the drain system remains functional, be it an internal or external pan .
You report , they decide. Hickabillies in Mo. don't much care about no code. 
Originally Posted By: Greg Owens This post was automatically imported from our archived forum.
maybe some of the installers decide not to use them because they believe the circuit board would get wet and fry causing the unit not to function…ha ha
Originally Posted By: kluce This post was automatically imported from our archived forum.
The information from state farm, that’s how we use to do it in Kentucky, In Indiana, we tee the secondary drain and the secondary drain pan together and run it out the house or to a drain if the furance is installed upright.
Ya just gotta love this job!