Thread: Unit in attic

Was wondering if there has to be a pan under the the furnace & a/c unit in the attic? Had one today that was put up on a platform but was directly on the wood platform. Also, what is the rule about florencent lights in the closets. Do they have to have covers or no? Thanks!

Similar Threads:

• Missing A/C Condensing Unit - Take 2
• A/C condensing unit location?
• Short Attic Ladder
• Protection of wiring in the attic
• Fireplace Had It's Own Air Handler Unit

As evident of what you saw, no, there's doesn't have to be a pan. Should there be a pan? - Yes.

Thanks Eric. Kinda what I though. Any idea bout the lights in closets?

Originally Posted by Eric Smith

Was wondering if there has to be a pan under the the furnace & a/c unit in the attic?

It depends.

It depends on the installation and the installation instructions.

What that means is that a pan is required ... unless ... and if those 'unless' conditions are *not* met, then, yes, a pan is required.

What that also means is that regardless of what they did to met those 'unless' conditions, *IF* the installation instructions state that a pan "shall" be installed, then ... *a pan shall be installed*. I have seen a few of the installation instructions which state "shall" be installed instead of the more usual "should" be installed, and in those cases the pan "shall" be installed.

Also, what is the rule about florencent lights in the closets. Do they have to have covers or no? Thanks!

410.16 Luminaires in Clothes Closets.
- (A) Luminaire Types Permitted. Listed luminaires of the following types shall be permitted to be installed in a closet:
- - (1) A surface-mounted or recessed incandescent luminaire with a completely enclosed lamp
- - (2) A surface-mounted or recessed fluorescent luminaire
- - (3) Surface-mounted fluorescent or LED luminaires identified as suitable for installation within the storage area
- (B) Luminaire Types Not Permitted. Incandescent luminaires with open or partially enclosed lamps and pendant luminaires or lampholders shall not be permitted.
- (C) Location. The minimum clearance between luminaires installed in clothes closets and the nearest point of a storage space shall be as follows:
- - (1) 300 mm (12 in.) for surface-mounted incandescent or LED luminaires with a completely enclosed light source installed on the wall above the door or on the ceiling
- - (2) 150 mm (6 in.) for surface-mounted fluorescent luminaires installed on the wall above the door or on the ceiling
- - (3) 150 mm (6 in.) for recessed incandescent or LED luminaires with a completely enclosed light source installed in the wall or the ceiling
- - (4) 150 mm (6 in.) for recessed fluorescent luminaires installed in the wall or the ceiling
- - (5) Surface-mounted fluorescent or LED luminaires shall be permitted to be installed within the storage space where identified for this use.

410.16(A)(2) allows the fluorescent fixture to be installed in a clothes closet.
410.16(C)(2) limits that to surface mounted fluorescent fixtures which are installed above the door or on the ceiling
410.16(C)(4) limits that to recessed fluorescent fixtures which are installed in the wall or the ceiling
410.16(C)(5) limits that to surface mounted fluorescent fixtures which are installed within the storage space where identified for that use. This means the fixture needs to be labeled with a label stating that the surface mounted fluorescent fixture is suitable for installation in the storage space in clothes closets.

Not the easy, cut and dried answer you were hoping for, is it?

Thanks Jerry.

The pan under the unit serves as a back-up pan.
What that means if the condensate line gets clogged and the water runs over it will go into the back-up pan which is usually connected to a drain pipe. This is basically a protection.
I usually install a condensate alarm in this pan which signals the homeowner to call and have this taken care of.
Not by code, just good business practice.

Backup drain pans are not required in NC if the requirements in #4 below are met.


307.2.3 Auxiliary and secondary drain systems.

In addition
to the requirements of Section 307.2.1, a secondary
drain or auxiliary drain pan shall be required for each cooling or evaporator coil or fuel-fired appliance that produces condensate, where damage to any building components will occur as a result of overflow from the equipment drain pan or stoppage in the condensate drain piping. One of the following
methods shall be used:
1. An auxiliary drain pan with a separate drain shall be
provided under the coils on which condensation will
occur. The auxiliary pan drain shall discharge to a
conspicuous point of disposal to alert occupants in the
event of a stoppage of the primary drain. The pan shall
have a minimum depth of 1.5 inches (38 mm), shall
not be less than 3 inches (76 mm) larger than the unit
or the coil dimensions in width and length and shall be
constructed of corrosion-resistant material. Metallic
pans shall have a minimum thickness of not less than
0.0276-inch (0.7 mm) galvanized sheet metal. Nonmetallic
pans shall have a minimum thickness of not
less than 0.0625 inch (1.6 mm).
2. A separate overflow drain line shall be connected to
the drain pan provided with the equipment. Such
overflow drain shall discharge to a conspicuous point
of disposal to alert occupants in the event of a stoppage
of the primary drain. The overflow drain line
shall connect to the drain pan at a higher level than the
primary drain connection.
3. An auxiliary drain pan without a separate drain line
shall be provided under the coils on which condensate
will occur. Such pan shall be equipped with a
water-level detection device conforming to UL 508
that will shut off the equipment served prior to overflow
of the pan. The auxiliary drain pan shall be constructed
in accordance with Item 1 of this section.
4. A water level detection device conforming to UL 508
shall be provided that will shut off the equipment
served in the event that the primary drain is blocked.
The device shall be installed in the primary drain line
upstream of the primary drain line trap, the overflow

drain line, or in the equipment-supplied drain pan,

located at a point higher than the primary drain line

connection and below the overflow rim of such pan.

As a past installer, present specifier and home owner I can say that I hate units in the attic. Very close to having them installed outdoors and in the summer it is worse. In the winter condensate piping can freeze, ducts and the walls of the unit experience more heat loss and gain, and the dang unit NEVER gets serviced.

Blame it on the mighty dollar, people don't want to give up floor space for mechanical equipment.

Great article here on units in attic.

It mentions a study that an AC unit in attic can use 30% more energy to do its job.

The other downfall is service maintenance can also increase significantly as it is a PITA and time consuming.

Does placing air handler in attic reduce system cooling effeciency? - HVAC-Talk: Heating, Air & Refrigeration Discussion

Zane

Don't know whether its required in whatever part of IL you are in. Drain pan is required in Chicago though.
Section 18-28-307.2.3