Horizontal HVAC unit

Specific Inspection Topics Inspecting HVAC Systems
1

Unit above condo bathroom.
No drain pan.

Anybody have a link to the requirement for one ?

Thanks in advance.

2

Common sense rule if the unit is above a finished ceiling it has to have a drain pan I just list it as a routine repair. If some contractor wants to challenge me on that he can provide the link that states its not a requirement;-)

3

I also call it out if the drain pan is not piped to the outside. Also a safety float switch on the pan and a pressure safety switch on the condensation line.

4

Most of the condo ceiling units I see (e.g., First Co.) have an integral drain pan and secondary discharge over the basin or tub in the bathroom

5

Here it pipes most likely into a independent dedicated drain but in this case could not enter the crawl and had to observe from the opening where it ran behind the unit. Also noticed it had leaked in the past from an elbow. Old high rise loft style conversion of factory built 1885 in 2004. I usually see pans and always call out lack of them but lost my source info. Water heaters have a code requiring where they can cause damage so yes common sense.

6

BOB

Most manufacturer’s of the AC equipment require it.

The International Mechanical Code also requires it. Here is the 2012 code:

307.2.3 Auxiliary and secondary drain systems. In addition to the requirements of Section 307.2.1, where damage to any building components could occur as a result of overflow from the equipment primary condensate removal system, one of the following auxiliary protection methods shall
be provided for each cooling coil or fuel-fired appliance that produces condensate:

  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 11/ 2 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. Galvanized sheet steel pans shall have a minimum thickness of not less than 0.0236 inch (0.6010 mm) (No. 24 gage). 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,
    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.

Exception: Fuel-fired appliances that automatically shut
down operation in the event of a stoppage in the condensate
drainage system.

307.2.3.1 Water-level monitoring devices. On downflow units and all other coils that do not have a secondary drain or provisions to install a secondary or auxiliary drain pan, a water-level monitoring device shall be installed inside the primary drain pan. This device shall shut off the equipment served in the event that the primary drain becomes restricted. Devices installed in the drain line shall not be permitted.

307.2.3.2 Appliance, equipment and insulation in pans. Where appliances, equipment or insulation are subject to water damage when auxiliary drain pans fill, that portion of the appliance, equipment and insulation shall be installed above the rim of the pan. Supports located inside of the pan to support the appliance or equipment shall be water resistant and approved.