This is a replacement drain cap and rubber washer for PolarCool evaporative coolers with a 3/4" drain outlet. If your reservoir drain is weeping or won't seal, this cap restores a tight fit and stops the leak.
This drain cap is a genuine PolarCool service part, built to hold up to repeated removal during routine reservoir maintenance. It's a small part, but a worn washer or cracked cap here is a common source of water on the floor under a cooler — this replacement addresses that directly. Note: If you would like to review the manufacturer Product Specifications, Warranty, Brochure, etc., for this system, please refer to the "Resources (System Manuals and Warranty)" Tab above on this page.
Critical Fitment & Requirements
- Drain outlet diameter: 3/4 in — confirm your unit's drain size before ordering.
- Includes rubber washer for sealing against the drain outlet.
- Pairs with drain outlet assembly SKU 6422-7010.
- Fits PolarCool models: 18, 24, 36, 36 Single Speed, 36 Pro (early black units only), 48.
- Does NOT fit all 36" Pro or Zone models.
- Later 36" Pro models use a 2" drain assembly (part number 6422-0722) — this 3/4" cap will NOT fit those units.
Key Benefits
- Direct-fit replacement designed for straightforward installation without modification.
- Rubber washer restores a tight seal against the drain outlet.
- Durable construction rated for repeated removal and reinstallation during routine service.
- Genuine PolarCool component matched to OEM drain outlet assembly SKU 6422-7010.
- Reduces service downtime with a fast swap during scheduled maintenance.
| Spec | Value | Unit |
|---|---|---|
| Drain Outlet Diameter | 3/4 | in |
| Sealing Component | Rubber washer | - |
| Compatible Drain Outlet Assembly SKU | 6422-7010 | - |
| Alternate Drain Assembly (later 36 Pro, incompatible) | 6422-0722 | - |
Note: See "Resources (System Manuals and Warranty)" Tab above for full specifications.
Compatibility & Fitment
- Fits PolarCool model families: 18, 24, 36, 36 Single Speed, 36 Pro, 48.
- Fits some early-version black 36" Pro units that use a 3/4" drain outlet.
- Compatible with drain outlet assembly SKU 6422-7010.
- Does NOT fit all 36" Pro or Zone models — verify drain size and configuration before ordering.
- Does NOT fit later 36" Pro units using the 2" drain assembly (part number 6422-0722).
| Item | Guidance |
|---|---|
| Material Handling | Rubber washer and cap component; inspect for wear or damage before each installation. |
| Installation Standard | Follow manufacturer installation guidelines for secure fitment and leak-free operation. |
FAQ
What size is this drain cap?
This is a 3/4" drain cap. It does not fit all 36" Pro or Zone models, so verify your drain size and configuration before ordering.
Will this fit my 36" Pro cooler?
Some early versions of the black 36" Pro use this 3/4" drain cap. Later 36" Pro models use a 2" drain assembly, part number 6422-0722, which this cap does not fit. Verify your drain size before ordering.
Does this include the rubber washer?
Yes. The replacement cap includes a rubber washer for sealing against the drain outlet. Inspect it for wear during installation to ensure a leak-free seal.
What drain outlet assembly does this pair with?
This cap is compatible with drain outlet assembly SKU 6422-7010.
Which PolarCool models use this cap?
It is used across the 18, 24, 36, 36 Single Speed, and 48 model lines, plus early black 36 Pro units with a 3/4" drain outlet.
Warranty & Registration
Manufacturer warranty terms for this component were not included in the source data provided. Refer to the "Resources (System Manuals and Warranty)" Tab above on this page for current PolarCool warranty documentation applicable to this part. [NEEDS VERIFICATION]
