Universal FloThru Spa Heater 4.0kW
Model: 48-1540-HS
Product Overview
We supply this versatile universal FloThru heater, designed to simplify repairs and maintenance across multiple spa models. This 15-inch heater represents the perfect balance of reliability, versatility, and performance for your hot tub heating needs.
Key Features
- Professional-grade 4.0kW heating element
- Universal 15″ length design
- Premium stainless steel construction
- Multiple pressure switch ports with stainless steel plugs
- Adjustable grounding and mounting studs
- Customizable thermowell cover position
- Complete with 2″ heater tailpieces including gaskets/o-rings
- Versatile union connections for easy installation
Universal Compatibility
This 4.0kW heater serves as a direct replacement for both 4.0kW and 4.5kW systems, making it a truly universal solution for multiple spa brands and models. The adjustable components ensure proper fit across various configurations.
Professional Benefits
- Streamlined inventory management
- Single-visit repair capability
- Wide compatibility across spa brands
- Time-saving installation features
- Robust construction for long-term reliability
Technical Specifications
| Specification | Detail |
|---|---|
| Model Number | 48-1540-HS |
| Voltage | 230V |
| Power Rating | 4.0kW |
| Length | 15 inches |
| Diameter | 2 inches |
| Connection Type | Union fittings |
| Construction | Stainless steel |
| Temperature Control | Adjustable thermowell |
| Mounting | Adjustable studs |
| Pressure Ports | Multiple (switch not included) |
| Application | Universal hot tub/spa |
Installation Notes
The adjustable design elements of this heater allow for custom positioning of key components, ensuring compatibility with your specific installation requirements. The unit comes complete with all necessary gaskets and O-rings for the tailpieces.
Compatibility
This universal heater is engineered to replace numerous OEM spa heaters across major brands and models. The adaptable design features ensure proper fitment in most standard spa configurations.
Note: Pressure switch sold separately
Below you will find information on specific heaters the universal heater can match.
| Picture | Part # | Description | Tube Length | Rating |
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46-371-1210 | Flo ThruHeater 4.0KW 2″x15″ PS/SI Brett/Caldera | 15″ | 4.0kW |
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46-371-1199 | Flo thruHeater 4.5KW 2″x15″ Hydroquip 5/97-Now | 15″ | 4.5kW |
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46-320-1165 | Flo ThruHeater Assy 2″x15″ PS/TI 4.0kW Brett | 15″ | 4.0kW |
🔧 Parts and fittings for this
| Part | Our part number | Availability | Price | ||
|---|---|---|---|---|---|
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Reducer Bushing Fitting 437-251 – 2"SPG x 1-1/2"S | 437-251 | 779 in stock | $5.02 | Add to cart |
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Tecmark Pressure Switch 3029 | 3029 | 170 in stock | $48.17 | Add to cart |
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Hydro-Quip Heater Cables 48-0023 | 48-0023 | 136 in stock | $6.98 | Add to cart |
Commonly replaced parts
Parts commonly replaced on this item that we stock.
| Part | Our part number | Availability | Price | ||
|---|---|---|---|---|---|
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Flow Thru Element, 4.0kW, Generic, 10", 230v, Titanium | 47-555-2525 | In stock | $79.99 | Add to cart |
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Split Nut, Waterway, 2", with Screws, Heater | 400-5161 | 306 in stock | $4.74 | Add to cart |
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Tailpiece, 2"bt x 2"s,for Split Nut | 417-5050 | 652 in stock | $4.04 | Add to cart |
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Waterway O-Ring/Gasket 711-4030 | 711-4030 | 3835 in stock | $0.73 | Add to cart |
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Band Clamp Kit, Hydro-Quip, Heater Repair, Quantity 2 | 48-0035 | 2 in stock | $13.17 | Add to cart |

















