Des Champs HVAC Air-Trap™ waterless trap allows liquid condensate to drain from the HVAC equipment and simultaneously prevents air from entering or escaping from the equipment.
DMS-Series
Why a Waterless Trap?
The DMS-Series Air-Trap allows water to drain from HVAC equipment and simultaneously prevents air from escaping from or entering the equipment by way of the condensate drain line.
The DMS-Series Air-Trap does not require standing water to prevent gas (typically air) from flowing through the condensate drain line. With the occurrence of condensate, or other water sources within the unit, the water flows out of the HVAC unit, but no gas enters or leaves. When there is no production of condensate or water, there is no water in the trap and there is no gas flow through the trap. Install the DMS-Series Air-Trap in a vertical orientation.
DMS Air-Traps will properly drain condensate for negative pressures to -1" WC and positive pressures to +5/8" WC while allowing essentially no air to enter or leave through the drain line. After condensate production ceases there will be no standing water within the drain line or trap if line is installed per code, i.e. 1/8" per foot slope or greater toward final drain point and no sags in the line.
DMS-Series Operation
Maximum Pressures, Connection Sizes and Lengths
Negative and/or Positive Pressure Waterless Trap
Features and Benefits
• Operates dry except when condensate is being produced
• Will not freeze and will never pass gas
• No sludge build-up in bottom of trap
• Easily comes apart for cleaning
• Operates under both positive and negative pressure
• Meets general building codes. For use on HVAC equipment only.
• Meets code IMC Section M307.2.4.1 for Ductless Mini-splits
Specifications
Maximum negative pressure of WC = -1"
Maximum positive pressure of WC = +5/8"
Available connection sizes:
• 3/4" (25 mm)
• 5/8" ID Drain Hose
Length 2.95 inches
Flammability rating is UL94 V-0
Air-Traps Meet IMC® Code Section M307.2.4.1
Available Models and Connection Sizes
• 3/4" (25 mm)
• 5/8" ID Drain Hose
HVAC Air-Trap
• Operates Dry — Eliminating:
- Freezing and breaking
- Dryouts
- Sludge buildup
- Geyser effect
- Mold and mildew caused by geyser effect
• Prevents air leakage
• Reduces trap height requirement by 1/2
• Predesigned — eliminating field-designed errors
No More Troublesome "P" Traps
Condensate Drain Line and Condensate Trap Code Requirements as Outlined in the 2024 UMC (Uniform Mechanical Code) and 2021 IMC (International Mechanical Code) for Mini-split AC Equipment
Click below button to see available sales locations and distributors
or purchase the DMS-Series below using the secure checkout from our Shopify store, waterless-trap.com
Negative/Positive Pressure
Vertical Orientation
Patented: US12130045B1
Preferred DMS-Series Installation
Preferred DMS Air-Trap installation for a ductless mini split for ease of cleaning trap and drain line.
For ease of maintenance and drain line cleaning the condensate trap location is best placed at the very end of the drain line as shown in Figure 4. Simply attach the DMS Air-Trap to the end of the drain line using plumber’s tape so that it can be easily removed from the line. Once removed, simply wash the trap with water to remove any debris.
2021 IMC Section 307.2.4.1 Ductless Mini-split system traps.
Ductless mini-split equipment that produces condensate shall be provided with an inline check valve in the drain line, or a trap.
The DMS-Series Air-Trap is specifically designed to serve as the inline check valve/trap for use with mini-split condensate lines.
2024 UMC Section 310.4. Appliance Condensate Drains. (excerpt)
Condensate drain lines serving more than one appliance connecting to a common indirect waste pipe shall have the connections to the indirect waste pipe protected by a sanitary waste valve complying with ASME A112.18.8, condensate trap complying with IAPMO IGC 196, or trap with a trap primer.
When multiple mini-split units are used to air-condition a building such as a school, nursing home, or condominium it is common practice to run individual condensate drain lines into a larger central drainpipe system that carries the water to a final disposal area. If this situation exists, the 2024 UMC code requires that each individual appliance drain line be fitted with a device as stated in Section 310.4 between the appliance and the common indirect waste pipe. The intent is to prevent air passage between conditioned spaces.
The DMS-Series Air-Trap meets the requirements of IAPMO IGC 196 and is designed for mini-splits, PTAC, and other fan-coil configurations.