Best Commercial Electric Tankless Water Heaters for Businesses
When choosing a commercial-grade electric tankless water heater, consider flow needs, electrical capacity, and space. This guide highlights five reliable options that suit small businesses, offices, salons, and light commercial setups. Each product is evaluated for best use cases, installation requirements, and potential limitations, helping you pick the right model for continuous hot water at point-of-use or whole-building scale. The following table summarizes key attributes to compare at a glance.
| Product | Best For | Power | Max Flow | |
|---|---|---|---|---|
| Rheem 18kW 240V Tankless Electric Water Heater | Small commercial spaces with moderate hot-water needs | 18 kW | Up to 4.4 GPM | External digital thermostat; copper elements |
| Rheem RTEX-24 24kW | Higher demand in compact spaces | 24 kW | Depends on inlet temp; continuous hot water | Requires multiple 40A breakers |
| WINTEMP 36kW Tankless | Mid-size commercial homes or offices with high demand | 36 kW | Up to 8.7 GPM | High amperage; 300A service recommended |
| Stiebel Eltron Tempra 29 Plus | Electric installations needing space savings | 28.8 kW | High efficiency, multiple memory presets | Hard-wired 240V supply required |
| APUS Tankless 4.5kW | Under-sink or single-point use in small offices | 4.5 kW | Low to moderate; best for 1 point | Ultra-compact; ideal for kitchens, bathrooms |
Rheem 18kW 240V Tankless Electric Water Heater
Best for small commercial kitchens or offices needing reliable on-demand hot water without a storage tank. Features include an external digital thermostat with LED display, self-modulating power to match demand, and durable copper immersion heating elements. Flow rate reaches up to 4.4 GPM, useful for single or two-point needs. A limitation is its smaller output, which may require staged installation for higher simultaneous hot-water use.
Rheem RTEX-24 24kW 240V Electric Tankless
Choose this for higher hot-water demand in compact spaces. It requires a robust electrical setup: 3 x 40A double-pole breakers and a 200A service recommended. It offers continuous hot water with on/off dial and adjustable temperature display from 80–140°F. Best for small offices or service areas where multiple fixtures might run simultaneously, but plan for electrical panel capacity and professional installation.
WINTEMP 36kW Tankless Electric 240V
Best for medium-to-large small commercial setups with higher hot-water needs. It features self-modulating technology for energy savings and stable temperature, with a maximum output of 8.7 GPM. Note the high installation requirements: 300A service recommended and four 40A double-pole breakers. It’s a strong choice where consistent, high-volume hot water is essential, but it requires careful electrical planning.
Stiebel Eltron Tempra 29 Plus
Ideal for businesses prioritizing space savings and efficient operation. The Tempra 29 Plus provides on-demand heat with no venting required and offers two temperature memory presets. It requires a hard-wired 240V service with a maximum draw of 28,800 watts. Best for small commercial spaces where multiple points of use need reliable hot water without bulky equipment.
APUS Tankless 4.5kW Under-Sink Heater
Best for point-of-use needs in small commercial environments like cafes or salons. The APUS unit provides instant hot water within seconds and uses self-modulating technology to improve efficiency. It’s compact and convenient for spaces where a full-size unit would be impractical. A limitation is its small capacity, making it unsuitable for higher flow demands.
Buying Guide
- Determine your flow needs. Estimate simultaneous hot-water usage across fixtures to choose a model with adequate GPM ratings.
- Assess electrical capacity. Higher-output units require substantial service (e.g., 300A for 36kW systems). Confirm panel space and breaker availability before purchase.
- Consider installation space. Wall-mounted units save floor space in compact commercial environments; plan clearances for service access.
- Evaluate temperature stability. Self-modulating models adjust power to maintain target temperatures, reducing energy waste and temperature fluctuations during peak use.
- Future-proofing. If expansion is possible, choose units with higher maximum flow and flexible installation options to avoid redoing electrical work later.
Frequently Asked Questions
- What size tankless heater do I need for a small business? Start with a model that supports your peak simultaneous hot-water demand in GPM, and ensure your electrical service can handle the unit’s power requirements.
- Are these units suitable for commercial kitchen use? Yes, but verify dishwasher and sink flow rates, and ensure proper water temperature stability and electrical readiness.
- Do I need professional installation? For high-power units, yes. Electric tankless heaters require correct wiring, grounding, and breaker planning for safety and performance.
- Can I vent these units? Most electric models do not require venting, which simplifies installation in many commercial settings.
- Will these reduce my energy bills? Self-modulating models reduce energy use by matching heat output to demand, which can lower operating costs compared with storage tanks.
- What maintenance is required? Regular inspections of electrical connections and flushing to remove mineral buildup are common practices to maintain performance.