Noritz or Thermomate? Tankless Water Heaters Compared in 2026
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The noritz vs thermomate tankless water heater debate often confuses buyers because these units serve different needs. Both provide hot water, but they operate on entirely different principles. Noritz offers a gas-powered outdoor tankless system for whole-house supply. Thermomate provides an electric mini-tank for point-of-use heating. You must choose based on your fuel source, installation space, and whether you need continuous flow or a single sink supply. This guide compares their key specifications to help you decide.
Key differences
| Aspect | Noritz Outdoor Propane Tankless Water Heater | Thermomate 6.5-Gallon Under-Sink Electric Mini-Tank |
|---|---|---|
| Fuel Type | Liquid Propane | Electric (120V) |
| Installation Location | Outdoor only | Under sink / Indoor |
| Capacity / Flow | 5.0 GPM continuous flow | 6.5 Gallons stored |
| Power Source | Gas burner (120,000 BTU) | 1.44 kW electric element |
Which one should you choose?
Choose Noritz Outdoor Propane Tankless Water Heater if
- You need hot water for multiple fixtures or outdoor use.
- You have a propane supply and outdoor mounting space.
- You want continuous hot water without running out.
Choose Thermomate 6.5-Gallon Under-Sink Electric Mini-Tank if
- You only need hot water for a single sink or faucet.
- You lack gas lines and have a 120V electrical outlet.
- You want a compact unit that fits under a counter.
Verdict: Choose the Noritz if you require high-volume hot water for outdoor or whole-house applications. Select the Thermomate if you only need to heat water for a single sink in a location without gas access. These products address distinct problems, so your choice depends on your specific plumbing and power setup.
Noritz vs Thermomate Spec Comparison
Fuel Type
You must choose between gas and electric power sources. Noritz uses liquid propane for its heating element. This allows it to operate independently of electrical grid limitations for heat generation. Thermomate relies on 120-volt electricity. This standard household voltage makes installation simpler in many locations. However, it limits the unit to point-of-use applications. Propane offers higher energy density for continuous flow. Electricity provides easier access but lower output capacity. Your available utility connections will dictate which system works for your home infrastructure.
Installation Location
Placement options differ significantly between these two units. Noritz is designed specifically for outdoor installation. Its construction withstands external weather conditions without additional housing. Thermomate is built for indoor, under-sink mounting. It fits into compact kitchen or bathroom cabinets. You cannot place the Thermomate outside due to its electrical components and tank design. Noritz cannot go inside without proper venting and clearance. Your physical space constraints will determine which unit fits your renovation plan.
Capacity
Water storage and flow capabilities vary greatly. Noritz delivers up to 5.0 gallons per minute of continuous hot water. It has no tank, so it heats water on demand. This supports multiple fixtures running simultaneously. Thermomate holds 6.5 gallons of stored hot water. It provides instant hot water at a single point of use. Once the tank empties, you must wait for recovery. Noritz suits whole-house needs. Thermomate suits small, isolated sinks. Your simultaneous hot water demand drives this choice.
Voltage
Electrical requirements define installation complexity. Noritz is a propane unit. It does not list specific voltage needs for its operation in the provided data, focusing on gas connection. Thermomate requires a 120-volt outlet. It draws 12 amps nominal current. This allows it to plug into standard household circuits. You do not need specialized gas lines for Thermomate. Noritz requires a propane tank and gas line. Your existing utility infrastructure determines which unit you can install without major upgrades.
Dimensions
Physical size affects where you can place the unit. Noritz measures 26.6 inches in height, 17.6 inches in width, and 10.7 inches in length. It weighs 33 pounds. This compact vertical footprint suits outdoor wall mounting. Thermomate measures 17.7 inches in width and length, with heights varying by model. The specific unit is 21.2 inches tall and weighs 26.5 pounds. Its cubic shape fits under sinks. Noritz is taller and narrower. Thermomate is wider and shallower. Your available space dimensions will filter the options.
Which Tankless Water Heater Fits Your Needs
Outdoor whole-house supply users
You need continuous hot water for multiple fixtures outdoors. Noritz delivers 5.0 GPM at 120,000 BTU using liquid propane. Its compact outdoor design fits tight spaces. You get high efficiency and low NOx emissions. This unit handles whole-house demand without storing water.
Under-sink point-of-use installers
You want instant hot water at a single sink. Thermomate provides 6.5 gallons of stored hot water. It plugs into a standard 120V outlet. The compact size fits under counters. You get adjustable temperature settings and freeze protection. This electric mini-tank reduces wait times for nearby fixtures.
RV or cabin propane users
You rely on propane for off-grid power. Noritz operates on liquid propane, not electricity. You get endless hot water without grid dependency. The unit weighs only 33 pounds. Its outdoor rating suits RVs or cabins. You avoid electrical load limits while maintaining high thermal efficiency.
The products compared
Noritz Outdoor Propane Tankless Water Heater
Best for: outdoor propane hot water needs
- Fuel Type
- Liquid Propane
- Flow Rate
- 5.0 Gpm
- BTU
- 120,000 Btuh
- Installation Location
- Outdoor
- Dimensions
- 26.6 x 17.6 x 10.7 inches
- Weight
- 33 pounds
View on Amazon: Noritz Outdoor Propane Tankless Water Heater Affiliate link
This Noritz unit delivers 5.0 GPM of hot water using 120,000 Btuh of power on liquid propane. It is built specifically for outdoor installation. The compact design measures 26.6 x 17.6 x 10.7 inches and weighs 33 pounds. You get endless hot water for outdoor showers or kitchen sinks. It operates with low NOx emissions and high efficiency. This model suits you if you need a reliable outdoor heat source.
Pros
- Provides 5.0 GPM flow rate
- High 120,000 Btuh heating power
- Designed for outdoor installation
- Runs on liquid propane fuel
Cons
- Limited to 5.0 GPM output
- Requires outdoor mounting only
- Uses liquid propane fuel only
Good fit if
- You need hot water for an outdoor kitchen
- You want to power an outdoor shower
- You have access to liquid propane
Skip if
- You need indoor installation
- You require natural gas connection
- You need more than 5.0 GPM
Verdict: Noritz NR50ODLP Outdoor Propane Heater delivers steady 5.0 GPM heat for outdoor tasks. It fits your patio or deck if you use propane.
Thermomate 6.5-Gallon Under-Sink Electric Mini-Tank
Best for: Single sink or vanity point-of-use hot water
- Fuel Type
- Electric
- Wattage
- 1.44 kW
- Capacity
- 6.5 Gallons
- Voltage
- 120V
- Temperature Control
- 50°F to 149°F
- Certification
- UL Listed
View on Amazon: Thermomate 6.5-Gallon Under-Sink Electric Mini-Tank Affiliate link
This Thermomate unit is a 6.5-gallon point-of-use electric water heater designed for under-sink installation. It operates on 120V power with a 1.44 kW heating element. The glass-lined tank offers 99% thermal efficiency and includes a thermostat adjustable from 50°F to 149°F. Its compact 17.7-inch dimensions fit standard cabinetry. It suits single fixtures like kitchen sinks or bathroom vanities where instant hot water is needed.
Pros
- 6.5-gallon capacity provides stored hot water for point-of-use applications
- 99% thermal efficiency reduces standby energy loss
- Adjustable thermostat allows temperature settings between 50°F and 149°F
- UL Listed for safety compliance
- Compact 17.7 x 17.7 x 14.6-inch design fits under sinks
Cons
- 1.44 kW heating element offers lower recovery rate than whole-home tankless units
- 6.5-gallon tank depletes quickly during high-demand scenarios
- 3-year limited warranty on tank is shorter than industry standards for tankless heaters
Good fit if
- You need hot water for a single sink or vanity
- You have a standard 120V outlet available near the installation point
- You want to reduce wait time for hot water at a specific fixture
Skip if
- You require simultaneous hot water for multiple fixtures
- You need a whole-home water heating solution
- You lack a nearby 120V electrical outlet
Verdict: Thermomate 6.5 Gallon Electric Mini Tank delivers efficient, localized hot water for single fixtures. It fits well in tight spaces where a full tankless system is unnecessary or impractical.
Specifications side by side
| Spec | Noritz Outdoor Propane Tankless Water Heater | Thermomate 6.5-Gallon Under-Sink Electric Mini-Tank |
|---|---|---|
| Fuel Type | Liquid Propane | Electric |
| Flow Rate | 5.0 Gpm | not stated |
| BTU | 120,000 Btuh | not stated |
| Wattage | not stated | 1.44 kW |
| Installation Location | Outdoor | not stated |
| Capacity | not stated | 6.5 Gallons |
| Voltage | not stated | 120V |
| Temperature Control | not stated | 50°F to 149°F |
| Certification | not stated | UL Listed |
| Dimensions | 26.6 x 17.6 x 10.7 inches | 17.7"H x 17.7"W x 14.6"D |
| Use | not stated | Under Sink |
| Weight | 33 pounds | 26.5 pounds |
| Color | Liquid Propane | white,blue |
| Model | NR501-OD-LP | ES700 |
| Size | not stated | 6.5 Gallon |
Frequently asked questions
Can I use the Noritz unit indoors?
No, the Noritz NR501-OD-LP is designed strictly for outdoor installation. Its casing and components are built to withstand weather exposure. Using it inside poses safety risks due to gas ventilation needs. You should only place this propane heater on a patio or deck where it is exposed to the open air.
Does the Thermomate provide hot water for the whole house?
No, the Thermomate ES is a point-of-use mini-tank. It holds only 6.5 gallons of water. This capacity is intended for a single sink or vanity. It cannot supply hot water to multiple fixtures or large showers. You need a larger system for whole-house coverage.
What fuel does the Noritz heater use?
The Noritz unit runs on liquid propane. You need a propane tank to power it. This fuel type allows for high heat output without relying on household electricity for the heating element. It is suitable for outdoor tasks where gas lines are not available.
Is the Thermomate compatible with standard 120-volt outlets?
Yes, the Thermomate operates on 120-volt electricity. This is the standard voltage for most household outlets. You do not need special high-voltage wiring for installation. This makes it easy to place under sinks or in cabinets where standard power is available.
How much space does the Noritz heater take up?
The Noritz NR501-OD-LP measures 17.6 inches wide, 26.6 inches high, and 10.7 inches long. It weighs 33 pounds. This compact footprint allows it to fit in tight outdoor spaces. You can mount it on a wall or place it on a deck surface.
Can I install the Thermomate under a bathroom sink?
Yes, the Thermomate is designed for under-sink installation. Its dimensions are 14.6 inches wide, 21.2 inches high, and 17.7 inches long. The white and blue color helps it blend in. It provides instant hot water for hand washing or brushing teeth.
What is the flow rate of the Noritz outdoor heater?
The Noritz unit delivers a flow rate of 5.0 gallons per minute. This volume is sufficient for outdoor cleaning tasks or filling large containers. It provides steady heat for continuous use. This rate supports multiple outdoor fixtures simultaneously without significant pressure drop.
Is the Thermomate heavy to move?
The Thermomate weighs 26.5 pounds. This weight is manageable for one person to lift and position. It is lighter than the Noritz unit. You can easily place it in tight cabinets or under vanishes without needing special lifting equipment.