---
The 81 gallons RV fresh water tank from ICON is built for RV owners replacing a damaged water tank or planning a custom plumbing layout around exact measurements. The WT3644 gives you an OEM-grade fresh water tank option sized at 58" x 44.5" x 7.75", which helps you compare compartment space before you commit to a replacement.
This ICON fresh water tank is best chosen by verified dimensions, listed capacity, and the specific fitting configuration shown for this model. If you are matching an existing RV water system, confirm the port layout from the product image before ordering.
Features & Specifications
- ICON WT3644 81 gallons RV fresh water tank for RV water system replacement or custom installs.
- Measures 58" x 44.5" x 7.75" for fitment planning before you order.
- Configured with 0335790 as listed by ICON.
- Made from impact-resistant polyethylene.
- BPA free and mold resistant for potable water use.
- Certified to IAPMO and CSA standards according to ICON product data.
Why Choose ICON WT3644?
This 81 gallons RV fresh water tank helps buyers solve the biggest tank-replacement problem: finding a tank that actually fits the available space. Instead of relying on a generic capacity match alone, you can use the 58" x 44.5" x 7.75" footprint and the listed configuration to compare against your current setup.
Because this 81 gallons RV fresh water tank is made by ICON and sold as an OEM-grade replacement part, it is a strong option for repair shops, renovators, and RV owners who need a dependable fresh water tank without guessing on basic specs.
Compare Fresh Water Tanks
Not sure which RV fresh water tank is right for your setup? Here is a quick comparison of verified ICON alternatives in our catalog.
| Model | Capacity | Dimensions | Best For | View Details |
|---|---|---|---|---|
| ICON WT3644 - Part WT3644 | 81 Gallons | 58" x 44.5" x 7.75" | RV tank replacement when you need this exact capacity and footprint. | Current Product |
| ICON WT3644 - Part WT3644 | 81 Gallons | - 44 1/2" x 58" x 7 3/4 -" | Nearby capacity alternative when your compartment dimensions are different. | View Details |
| ICON WT3555 - Part WT3555 | 75 Gallons | 50" x 36" x 10" | Nearby capacity alternative when your compartment dimensions are different. | View Details |
| ICON WT3555 - Part WT3555 | 75 Gallons | 50" x 36" x 10" | Nearby capacity alternative when your compartment dimensions are different. | View Details |
Tip: Match the tank by dimensions and fitting layout first, then use gallon capacity as a secondary check.
Technical Specifications
- Brand: ICON
- Part Number: WT3644
- Capacity: 81 Gallons
- Dimensions: 58" x 44.5" x 7.75"
- Configuration: 0335790
- Material: Impact-resistant polyethylene
- Certifications: IAPMO and CSA
What's Included
- One ICON WT3644 fresh water tank.
- No additional fittings, hardware, or accessories unless shown or stated in the product configuration.
Compatible Models & Alternatives
If this tank is close but not exact for your RV, compare these verified ICON fresh water tank alternatives:
- ICON - 81 Gallon RV Fresh Water Tank - 44 1/2" x 58" x 7 3/4" - WT3644
- ICON - Fresh Water Tank, WT3555, 50x36x10, 75 Gallons, 0318083
- ICON - Fresh Water Tank, WT3555, 50x36x10, 75 Gallons, Tank Only
Frequently Asked Questions
Is this 81 gallons RV fresh water tank safe for drinking water?
ICON states its fresh water tanks are BPA free, mold resistant, and safe for drinking water.
How do I know if this ICON WT3644 tank will fit my RV?
Measure your available compartment space and compare it to the listed 58" x 44.5" x 7.75" dimensions before ordering.
Does this tank include fittings?
Use the listed configuration and product image to confirm the included fitting layout for this model.
Can I use this tank for a custom RV build?
Yes. Many buyers use ICON fresh water tanks for custom installs, but you should verify dimensions and port layout before purchase.
What is the best way to choose between similar RV fresh water tanks?
Start with exact dimensions and fitting layout, then compare gallon capacity and installation constraints.
Why Buy from Elkhart RV Parts?
Elkhart RV Parts carries OEM-grade RV replacement parts with verified product data, fast catalog access, and real comparison options so you can buy the right tank with more confidence.
| Product type | Fresh Water Tank |
|---|---|
| Brand | ICON |
| Model | WT3644 |
| Capacity | 81 Gallons |
| Dimensions | 58 x 44.5 x 7.75 inches |
| Material | Polyethylene |
| Impact resistant | true |
| Bpa free | true |
| Mold resistant | true |
| Drinking water safe | true |
| Certifications | IAPMO, CSA |
| Oem part number | 0335790 |
| Replaces | Jayco 0335790 |
| Shipping | LTL Only |
| Configuration options | Tank only or with pre-installed fittings |
- What material is the icon fresh water tank made from? The ICON Fresh Water Tank is made of durable and impact resistant polyethylene.
- Is the icon fresh water tank safe for drinking water? Yes, the tank is BPA free, mold resistant, and certified safe for drinking water.
- What are the dimensions of the icon fresh water tank? The tank dimensions are 58 inches by 44.5 inches by 7.75 inches.
- What is the capacity of the icon fresh water tank? The tank has a capacity of 81 gallons.
- Does the icon fresh water tank come with pre-installed fittings? There are many options available, including tanks only or tanks with pre-installed fittings. Please check the specific product option before ordering.
Factory-Fresh OEM Parts — the same brands installed in new RVs straight from Elkhart. Genuine, name-brand components made to order — never generic, never outdated. Sourced directly from the original RV manufacturers for perfect fit and factory-level quality.