Top 28 4 GPM Tankless Water Heaters on Amazon (Verified You can Buy)
CAMPLUX 2.64 GPM Portable Tankless Water Heater, Outdoor Water Heater Propane with 4.3'' S/S Rain Cap, On Demand Propane Hot Water for Camping, Cabins, Outdoor Use
CAMPLUX ENJOY OUTDOOR LIFE
BD264C N1
13.0 x 13.0 x 28.5 Inches
18.0 Pounds
Ratings for CAMPLUX ENJOY OUTDOOR LIFE (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| Camplux | - | ❌ | ❌ | ❌ |
| Amazon Resale | - | ❌ | ❌ | ❌ |
Features
【Propane On Demand Hot Water】Portable water heater is rated at 2.64 GPM and has 68,000 BTU/hour maximum heat output. No need for complex settings, with LED display & gas/water flow control knobs, easily get the temperature rise at 50°F-122°F
【Effortless Installation in 5 Minutes】Size 13.0(L)*7.3(W)*28.5(H with Cap) inches, weight 18 lbs. Includes pre-installed gas regulator and quick connect ON/OFF shower kit. Simply connect water inlet and outlet, attach 20lb propane tank, insert 2D batteries, put rain cap on the top, you're ready to go
Vancepic Natural Gas Tankless Water Heater Indoor,4.3 GPM | 3-4 Point Use for Family, 100,000 BTU, on Demand Instant Hot Water Heater with LED Display, Silent operation, Child Lock Design
VancEpic
VH10K-W-NG-U01
14.4 x 14.4 x 24.6 inches
25.1 Pounds
Ratings for VancEpic (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| Vancepic WarmHome Mall | - | ❌ | ❌ | ❌ |
Features
𝐀𝐢𝐫𝐁𝐨𝐨𝐬𝐭 𝐂𝐨𝐦𝐛𝐮𝐬𝐭𝐢𝐨𝐧, 𝐏𝐨𝐰𝐞𝐫𝐟𝐮𝐥 𝐇𝐨𝐭 𝐖𝐚𝐭𝐞𝐫: AirBoost preheated air technology enhances combustion efficiency, delivering up to 100,000 BTU and 4.3 GPM continuous hot water. This natural gas tankless water heater easily supports 3-4 water outlets for whole-house hot water needs.
±𝟏°𝐅 𝐏𝐫𝐞𝐜𝐢𝐬𝐞 𝐓𝐞𝐦𝐩𝐞𝐫𝐚𝐭𝐮𝐫𝐞 𝐂𝐨𝐧𝐭𝐫𝐨𝐥: Intelligent gas water and temperature linkage automatically adjusts heating output to maintain water temperature within ±1°F. Enjoy stable, comfortable hot water without sudden temperature fluctuations.
Tankless Water Heater 4.75 GPM Natural Gas Constant Hot Water
Amzgachfktch
FM-WHAQ3016W
13.7 x 13.7 x 21.6 inches
Ratings for Amzgachfktch (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| FanmiTechnology | - | ❌ | ❌ | ❌ |
Features
【Endless Constant Hot Water for Whole-Home Use】Delivers a powerful 4.75 GPM flow rate, supporting up to 3-4 fixtures simultaneously—shower, kitchen faucet, and bathroom sink all at once. Powered by a robust 102,000 BTU natural gas burner, this hot water heater provides instant temperature rise and an endless supply of hot water on demand. No more cold shocks when someone flushes a toilet or turns on another tap; every family member enjoys steady, uninterrupted hot water.
【Advanced Precision Temperature Stability (±1°F)】Featuring advanced water servo technology and high-sensitivity temperature sensors, this instant hot water heater precisely adjusts water flow and gas intake in real-time to maintain temperature stability within ±1°F—even when water pressure fluctuates or multiple fixtures are running simultaneously. No more unexpected cold blasts or scalding surprises; just set your ideal temperature (95°F–149°F) and let the system deliver consistent, comfortable hot water on demand.
Top 4
27kW Tankless Water Heater Electric, NOVIEEX 240V 3s Instant Hot Water Heater, Flow Rate Max 7.4 GPM, Supply for 3-4 Points, Indoor Installation, Heavy Duty Ideal for Whole House Use
NOVIEEX
DS-18
14.13 x 14.13 x 15.86 Inches
Ratings for NOVIEEX (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| NOVIEEX Global | - | ❌ | ❌ | ❌ |
Features
【HIGH-POWER 27kW PERFORMANCE】 Built for demanding hot water needs, this 27kW tankless water heater delivers high-power heating performance at 240V, with a maximum current of 112.5A. It requires 3 × 40A double-pole circuit breakers and 3 sets of 8 AWG wires with a ground wire. The unit measures 14.13" (W) × 15.86" (H) × 3.18" (D) and features 3/4" NPT water connections. Please consult a qualified electrician and verify that your electrical system meets the requirements before purchasing.
【WHOLE HOUSE HEAVY DUTY】 The NOVIEEX 27kW tankless hot water heater electric is a heavy-duty solution custom-built to satisfy full household demands. Designed to seamlessly supply larger homes, its streamlined wall-mount enclosure saves 80% more space than mammoth 50+ gallon storage tanks, inserting perfectly into narrow closets or compact utility spaces.
Top 5
Best for 5 GPM
Ranein Propane Gas Tankless Water Heater, 5.3 GPM, 130,000 BTU, Indoor
Ranein
RH13K-LPG
14.17 x 14.17 x 23.15 Inches
38.0 Pounds
Ratings for Ranein (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| Ranein Store | - | ❌ | ❌ | ❌ |
Features
Fans Placed Underneath: It will be more secure in terms of safety, and no smoke backflow will occur. The blower has large power and can automatically adjust the rotating speed according to the change of external wind pressure and the change of water temperature to provide sufficient oxygen for gas combustion, ensuring full combustion and safer use. Low noise and longer service life.
No Waiting Required: Unlike traditional tank water heaters, tankless water heaters eliminate the need for a 30-minute preheating wait time, allowing you to have unlimited hot water on demand.
Top 6
Best for Residential
ThermoMate 98,500 Propane Tankless Water Heater, Up to 4 GPM, High Efficiency Instant On-Demand Hot Water for Whole House Use, Indoor Residential Water Heater with Multi-Point Heating, CZ360LP
thermomate
CZ360LP
13.77 x 13.77 x 21.65 Inches
21.16 Pounds
Ratings for thermomate (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| ThermoMate Official | - | ❌ | ❌ | ❌ |
Features
[Max 4 GPM & 98,500 BTU] - The ThermoMate instant water heater delivers water hot enough for simultaneous use— at 105°F to a shower (2 GPM) and a kitchen faucet (1 GPM) — from a 62°F inlet. It reliably supplies a comfortable single shower even with a 40°F inlet temperature. No waiting time, no cold water shocks, perfect for busy households. With an advanced flow sensor, its built-in chip regulates heating 20,000 times/sec to keep water temperature within ±1°F for a stable.
[Safety & Reliable] - This gas tankless water heater integrates 8 protections: boil-dry, freeze, flame-out, overheating, over-temperature, pipe blockage, high-temperature lock, and excessive air pressure. Equipped with 4 ceramic heating cores, it auto-activates frost protection when temperatures hit 41°F (5℃). The energy-smart system uses minimal electricity to generate gentle warmth, preventing pipe ice buildup without high energy costs.
Top 7
Best for Propane
Best Gas Water Heaters
Best for 40 Gallon
Best for 50 Gallon
Best for 60 Gallon
Best for Tankless
Novieex Propane Gas Tankless Water Heater Up to 4.3 GPM 100,000 BTU, Indoor
NOVIEEX
RS-16
13.78 x 13.78 x 23.23 inches
19.84 Pounds
Ratings for NOVIEEX (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| NOVIEEX Global | - | ❌ | ❌ | ❌ |
| Woot | 115 | ❌ | ❌ | ❌ |
Features
【Note 】 This 4.3GPM propane gas model. Gas rated pressure: 11.24" w.c. (2.8 kPa), Gas Inlet & Cold Water Inlet & Hot Water Outlet：NPT 1/2", Power Supply: 110V-120V AC/60Hz, Water Pressure Range: 1.5-116 psi (0.01-0.8MPa)
【Reliable Hot Water on Demand】 With 100,000 BTU power, this on demand water heater delivers up to 4.3 GPM instant hot water. You can comfortably run a shower, kitchen faucet, and bathroom sink simultaneously—all without any noticeable temperature drop.
Top 8
Best for Rheem
Best for Inline
Best for Tanked
Best for Electric
Best for NG
Best for Thermostat
Best for Whole House
Best for Rheem
Best Tankless Water Heaters
Best for Takagi
Best for Noritz
Best for Rheem
Best for Rinnai
Best for EcoSmart
Best for FOGATTI
Best for GASLAND
Best for Eccotemp
Best for AO Smith
Best for 2 GPM
Best for 5 GPM
Best for 7 GPM
Best for 8 GPM
Best for 9 GPM
Best for 10 GPM
Best for 11 GPM
Best for 12 GPM
Best for 14 GPM
Best for 15 GPM
Rheem 11kW 240V Tankless Electric Water Heater
Rheem
RTEX-11
12.63 x 8.25 x 3.63 inches
7.0548 Pounds
99,8%
Ratings for Rheem (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| Amazon.com | - | ✅ | ✅ | ✅ |
| Plumber's Paradise | - | ✅ | ✅ | ✅ |
| CASA CAYOS | - | ✅ | ✅ | ✅ |
| AXY Co | - | ✅ | ✅ | ✅ |
| Amazon Resale | - | ❌ | ❌ | ❌ |
| Trena's Liquidation LLC | - | ❌ | ❌ | ❌ |
| MTL Retailers | - | ❌ | ❌ | ❌ |
Features
ON/OFF Dial Control with adjustable digital temperature display
Self-modulating power control
Top 9
Best for Whole House
Best for 80 Gallon
Best for 2 GPM
Best for 8 GPM
Best for 9 GPM
Best for 12 GPM
Best for 14 GPM
18kW Tankless Water Heater Electric 240V WINTEMP, On Demand Instant Hot Water Heater, Up to 4.3 GPM, with LED Temperature Display, Whole House Hot Water Supply, WiFi Control, ETL Certified
WINTEMP
WN18
19.1 x 11.1 x 4.0 inches
12.0 pounds
Ratings for WINTEMP (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| WINTEMP | - | ❌ | ❌ | ❌ |
Features
Important Note: Ensure this tankless water heater meets your installation requirements, 150 Amp Household Service Recommended. The WN18 model is rated at 18KW (240V) with a maximum amperage of 75A. It requires 2 x 40 Amp DP breakers and 2 x 8/2 AWG wiring with ground. The unit dimensions are 11.1” (W) x 19.1 ” (H) x 4” (D), the water connection is 3/4" NPT, Please consult a qualified electrician before purchasing
Stable Water Temperature: Automatically adjusts energy consumption based on incoming water temperature and flow rate to ensure maximum efficiency, continuous stable temperature, and optimal power usage. Its maximum hot water output is 4.3 gallons per minute. It is perfect for residential shower use, eliminating the need to wait for preheating. There’s no longer any concern about running out of hot water in the tank, and you won’t experience temperature fluctuations during your shower. Provides continuous hot water for showers and everyday household use
WINTEMP 36kW Tankless Electric Water Heater 240V, Instant On-Demand Endless Hot Water, Up to 8.7 GPM, LED Temperature Display, Whole House Supply, WiFi Control, ETL Certified
WINTEMP
WN36
13.7 x 13.7 x 21.1 Inches
36.05 Pounds
Ratings for WINTEMP (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| WINTEMP | - | ❌ | ❌ | ❌ |
Features
Important Note: Please ensure this tankless water heater meets your installation requirements, 300 Amp Household Service Recommended. The WN36 model is rated at 36KW (240V) with a maximum current draw of 150A. It requires 4 x 40 Amp double-pole (DP) breakers and 4 x 8/2 AWG cables with ground. A 300A household power supply is recommended. Unit dimensions: 13.7” (W) x 21.1” (H) x 5.3” (D). Water connection: 3/4" NPT, Please consult a qualified electrician before purchasing
Stable Water Temperature: Automatically adjusts energy consumption based on incoming water temperature and flow rate to ensure maximum efficiency, a consistently stable temperature, and optimal power usage. With a maximum hot water output of 8.7 gallons per minute, it’s ideal for residential showers — no need to wait for preheating, no risk of running out of hot water, and no more temperature fluctuations during your shower. Provides continuous hot water for showers and everyday household use
FOGATTI Propane Gas Tankless Water Heater Outdoor - Max 5.1 GPM 120,000 BTU, CSA Certified Compact Design On Demand Instant Hot Water Heater - Instagas Comfort 120S Series
FOGATTI
120S
15.5 x 15.5 x 23.9 inches
29.3 Pounds
Ratings for FOGATTI (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| Westinghouse Home Comfort Direct | - | ❌ | ❌ | ❌ |
Features
Efficient Tankless Heating: The FOGATTI tankless water heater propane occupies only a third of the size of traditional heaters while delivering five times the performance. With 120,000 BTU and 5.1 GPM flow rate, it provides instant, endless hot water, supporting 2-4 outlets at once, making it perfect for whole house with medium family
Excellent Value: The tankless water heater provides excellent value with top performance at low energy costs. Its eco-efficient design helps reduce energy bills while saving space. Offering reliable hot water on demand, it ensures you get great value for the investment, combining efficiency, savings, and convenience
CAMPLUX Climatech 7 Tankless Water Heater Propane 3.6 GPM Up to 4 GPM, 85,300 BTU CSA Certified On Demand Instant Propane Tankless Hot Water Heaters Indoor, 1-3 Points Real Data No Exaggeration
CAMPLUX ENJOY OUTDOOR LIFE
CA360WLP
13.8 x 13.8 x 6.7 inches
21.2 Pounds
Ratings for CAMPLUX ENJOY OUTDOOR LIFE (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| Camplux | - | ❌ | ❌ | ❌ |
Features
𝟑.𝟔 𝐆𝐏𝐌(Max 4 GPM) 𝐓𝐚𝐧𝐤𝐥𝐞𝐬𝐬 𝐏𝐫𝐨𝐩𝐚𝐧𝐞 𝐖𝐚𝐭𝐞𝐫 𝐇𝐞𝐚𝐭𝐞𝐫: The Camplux CA360W delivers powerful 85,300 BTU(Real Data, No Exaggeration) performance for simultaneous hot water in 2-3 zones—showers, kitchen, and laundry. Up to 4 GPM, each delivering 105°F water at a flow rate of 2 GPM, based on an inlet water temperature of 65°F. Enjoy 100% continuous flow: baths and dishwashers run without interruption. Suitable for Whole house, Tiny home, Mobile home, Apartment, Rental property (for rent), RV, Cabin.
𝐒𝐦𝐚𝐫𝐭, 𝐄𝐟𝐟𝐢𝐜𝐢𝐞𝐧𝐭 𝐈𝐧𝐬𝐭𝐚𝐧𝐭 𝐏𝐫𝐨𝐩𝐚𝐧𝐞 𝐇𝐨𝐭 𝐖𝐚𝐭𝐞𝐫 = 𝐒𝐞𝐫𝐢𝐨𝐮𝐬 𝐒𝐚𝐯𝐢𝐧𝐠𝐬: Get hot water fast, precisely when you need it. Intelligent gas control optimizes usage year-round, and our premium heat exchanger delivers maximum efficiency. Stop paying to heat water you don't use – start saving money today. 0.93 UEF rating saves $168/year vs. standard models (CSA guidelines). Saves $150+/year on utility bills - 100% recirculation ready.
Top 13
Best for Inline
Best for Indoor
Best for Whole House
Best for Residential
Best for High Efficiency
Best Gas Water Heaters
Best for 30 Gallon
Best for 40 Gallon
Best for 50 Gallon
Best for 60 Gallon
Best for 75 Gallon
Best for 80 Gallon
Best for Tankless
Best for Rinnai
Best for 3 GPM
Best for 5 GPM
Best for 7 GPM
Best for 9 GPM
ThermoMate CZ422NG Natural Gas Tankless Water Heater, Up to 5 GPM 113,000 BTU, High Efficiency Instant On-Demand Hot Water for Whole House Use, Indoor Residential Water Heater with Multi-Point Heating
thermomate
CZ422NG
13.77 x 13.77 x 21.65 inches
22.0 Pounds
Ratings for thermomate (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| ThermoMate Official | - | ❌ | ❌ | ❌ |
Features
[Max 5 GPM & 113,000 BTU] - The ThermoMate instant hot water heater can supply two showers simultaneously, each delivering 105°F water at a flow rate of 2 GPM, based on an inlet water temperature of 65°F. No waiting time, no cold water shocks, perfect for busy households. Adopting advanced water flow sensor, the built-in chip can adjust the heating power 20,000 times per second, ensuring that the hot water within ±1℉ fluctuations for a comfortable shower experience.
[Safety & Reliable] - This gas tankless water heater integrates 8 protections: boil-dry, freeze, flame-out, overheating, over-temperature, pipe blockage, high-temperature lock, and excessive air pressure. Equipped with 4 ceramic heating cores, it auto-activates frost protection when temperatures hit 41°F (5℃). The energy-smart system uses minimal electricity to generate gentle warmth, preventing pipe ice buildup without high energy costs.
Top 14
Best Gas Water Heaters
Best for 30 Gallon
Best for 40 Gallon
Best for 50 Gallon
Best for 60 Gallon
Best for 75 Gallon
Best for 80 Gallon
Best for Tankless
Tankless Water Heater, Novieex On Demand Water Heater Natural Gas, Up to 4.3 GPM, 100,000 BTU Instant Hot Water Heater with LED Display, Indoor Installation, 2-4 Point Use for Family Bathroom Kitchen
NOVIEEX
RS-16
28.54 x 17.32 x 10.83 Inches
19.84 pounds
Ratings for NOVIEEX (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| NOVIEEX Global | - | ❌ | ❌ | ❌ |
| Amazon Resale | - | ❌ | ❌ | ❌ |
| Woot | 115 | ❌ | ❌ | ❌ |
Features
【Note 】 This is 4.3GPM natural gas model. Gas rated pressure: 8.04" w.c. (2.0 kPa), Gas Inlet & Cold Water Inlet & Hot Water Outlet：NPT 1/2", Power Supply: 110V-120V AC/60Hz, Water Pressure Range: 1.5-116 psi (0.01-0.8MPa)
【Reliable Hot Water on Demand】 With 100,000 BTU power, this on demand water heater delivers up to 4.3 GPM instant hot water. You can comfortably run a shower, kitchen faucet, and bathroom sink simultaneously—all without any noticeable temperature drop.
Top 15
Best for Residential
ThermoMate 98,500 Natural Gas Tankless Water Heater, Up to 4 GPM, High Efficiency Instant On-Demand Hot Water for Whole House Use, Indoor Residential Water Heater with Multi-Point Heating, CZ360NG
thermomate
CZ360NG
13.7795 x 13.7795 x 21.6535 inches
Ratings for thermomate (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| ThermoMate Official | - | ❌ | ❌ | ❌ |
Features
[Max 4 GPM & 98,500 BTU] - The ThermoMate instant water heater delivers water hot enough for simultaneous use— at 105°F to a shower (2 GPM) and a kitchen faucet (1 GPM) — from a 62°F inlet. It reliably supplies a comfortable single shower even with a 40°F inlet temperature. No waiting time, no cold water shocks, perfect for busy households. With an advanced flow sensor, its built-in chip regulates heating 20,000 times/sec to keep water temperature within ±1°F for a stable.
[Safety & Reliable] - This gas tankless water heater integrates 8 protections: boil-dry, freeze, flame-out, overheating, over-temperature, pipe blockage, high-temperature lock, and excessive air pressure. Equipped with 4 ceramic heating cores, it auto-activates frost protection when temperatures hit 41°F (5℃). The energy-smart system uses minimal electricity to generate gentle warmth, preventing pipe ice buildup without high energy costs.
FOGATTI Natural Gas Tankless Water Heater Indoor - Max 5.1 GPM 120,000 BTU, CSA Certified Compact Design On Demand Instant Hot Water Heater - Instagas Comfort 120S Series
FOGATTI
InstaGas Comfort
15.5 x 15.5 x 23.9 Inches
Ratings for FOGATTI (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| Westinghouse Home Comfort Direct | - | ❌ | ❌ | ❌ |
Features
Powerhouse Performance: The FOGATTI tankless water heater takes up a third of the space of traditional tank heaters but delivers 5 times the performance. With a high heating power of 120,000 BTU and a flow rate of 5.1 GPM, it provides endless hot water on demand, perfect for multitasking households
Instant Heating: Unlike traditional tank heaters, this tankless water heater gas delivers instant and endless hot water as water flows through. Whether it’s for showers, sinks, or appliances, even for 2-4 outlet points, it ensures uninterrupted hot water whenever you need it
FOGATTI Propane Gas Tankless Water Heater Indoor - Max 5.1 GPM 120,000 BTU, CSA Certified Compact Design On Demand Instant Hot Water Heater - Instagas Comfort 120S Series
FOGATTI
InstaGas Comfort
15.5 x 15.5 x 23.9 inches
Ratings for FOGATTI (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| Westinghouse Home Comfort Direct | - | ❌ | ❌ | ❌ |
Features
Powerhouse Performance: The FOGATTI tankless water heater takes up a third of the space of traditional tank heaters but delivers 5 times the performance. With a high heating power of 120,000 BTU and a flow rate of 5.1 GPM, it provides endless hot water on demand, perfect for multitasking households
Instant Heating: Unlike traditional tank heaters, this tankless water heater propane delivers instant and endless hot water as water flows through. Whether it’s for showers, sinks, or appliances, even for 2-4 outlet points, it ensures uninterrupted hot water whenever you need it
FOGATTI Propane Gas Tankless Water Heater Indoor - Max 7.5 GPM 170,000 BTU, CSA Certified Compact Design On Demand Instant Hot Water Heater - Instagas Comfort 170S Series
FOGATTI
InstaGas Comfort
16.3 x 16.3 x 25.0 inches
Ratings for FOGATTI (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| Westinghouse Home Comfort Direct | - | ❌ | ❌ | ❌ |
Features
Powerhouse Performance: The FOGATTI tankless water heater takes up a third of the space of traditional tank heaters but delivers 5 times the performance. With a high heating power of 170,000 BTU and a flow rate of 7.5 GPM, it provides endless hot water on demand, perfect for multitasking households
Instant Heating: Unlike traditional tank heaters, this tankless water heater propane delivers instant and endless hot water as water flows through. Whether it’s for showers, sinks, or appliances, even for 3-5 outlet points, it ensures uninterrupted hot water whenever you need it
APUS Tankless Water Heater Natural Gas, Up to 5.43 GPM, Indoor Tankless Water Heater, 120,000 BTU on Demand Instant Hot Water Heaters with Smart Digital Display,Space Gray
APUS
AP-AWH-Q16NG
19.29 x 19.29 x 27.59 Inches
19.18 pounds
High
Ratings for APUS (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| APUS WATER EQUIPMENT | - | ❌ | ❌ | ❌ |
Features
Powerful & High-Capacity: This high-performance gas tankless water heater delivers 120,000 BTU heating capacity with 5.43 GPM high flow rate, featuring innovative 0.66GPM low-flow start technology. As a versatile natural gas tankless water heater, it meets simultaneous hot water demands for 2 showers plus 1 sink while maintaining stable temperatures even during peak usage.
Precise & Steady: With high-precision sensors and smart CPU technology, this tankless gas water heater maintains water temperature within ±1°F of your desired setting (adjustable from 95°F-140°F). No more sudden hot/cold shocks—just perfectly steady water for showers, washing, and more, even with multiple faucets running. Enjoy worry-free comfort every time!
Top 20
Best Gas Water Heaters
Best for 30 Gallon
Best for Tankless
Best for Eccotemp
Best for 5 GPM
Best for 10 GPM
Best for 14 GPM
Ranein Propane Gas Tankless Water Heater, Indoor Max 4.3 GPM, 100,000 BTU Instant Hot Water Heater
Ranein
RANEIN-43GPM-100KBTU
14.1732 x 14.1732 x 22.5079 inches
Ratings for Ranein (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| Ranein Store | - | ❌ | ❌ | ❌ |
| Woot | 115 | ❌ | ❌ | ❌ |
Features
Powerful On-Demand Heating: 100,000 BTU & 4.3 GPM for this tankless water heater propane, supports 3-4 water points simultaneously, delivers endless propane hot water on demand with no waiting.
4 Intelligent Preset Modes: One-click switch for 4-season/Kitchen/Bathtub/Shower modes on the propane tankless water heater; 4-season auto-matches temp, kitchen defaults to 100°F, bathtub supports 50-800L volume adjustment.
Top 21
Best Gas Water Heaters
Best for Tankless
Best for Takagi
Best for AO Smith
Best for 2 GPM
Best for 5 GPM
Best for 6 GPM
Best for 8 GPM
Best for 9 GPM
Ranein Propane Gas Tankless Water Heater, Indoor Max 8.5 GPM, 190,000 BTU Instant Hot Water Heater
Ranein
RH19K-LPG
15.08 x 15.08 x 24.25 inches
42.0 Pounds
Ratings for Ranein (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| Amazon Resale | - | ❌ | ❌ | ❌ |
| Ranein Store | - | ❌ | ❌ | ❌ |
Features
Fans Placed Underneath: It will be more secure in terms of safety, and no smoke backflow will occur. The blower has large power and can automatically adjust the rotating speed according to the change of external wind pressure and the change of water temperature to provide sufficient oxygen for gas combustion, ensuring full combustion and safer use. Low noise and longer service life.
No Waiting Required: Unlike traditional tank water heaters, tankless water heaters eliminate the need for a 30-minute preheating wait time, allowing you to have unlimited hot water on demand.
GASLAND Outdoors 16L Propane Tankless Water Heater 4.22GPM, On Demand Propane Hot Water Heater for Off Grid, Adjustable Temperature, Overheating Protection, Easy to Install, Black, BE422B
GASLAND
BE422
15.7 x 15.7 x 25.6 Inches
Ratings for GASLAND (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| Gasland | - | ❌ | ❌ | ❌ |
Features
4.22𝗚𝗣𝗠/16𝗟 𝗣𝗿𝗼𝗽𝗮𝗻𝗲 𝗪𝗮𝘁𝗲𝗿 𝗛𝗲𝗮𝘁𝗲𝗿 - Maximum power output 11,0000BTU/Hr.The temperature raise is 109.4℉ (43℃) at its highest point and 55.4℉ (13℃) is at its lowest point of 1.58 GPM. Also, 1.58 gallons of hot water can be produced per minute at the flow rate of 4.22 GPM. Low water pressure start up, just need 4.0 PSI of water pressure to start.
𝗚𝗼𝗼𝗱 𝗳𝗼𝗿 𝗢𝗳𝗳-𝘁𝗵𝗲-𝗚𝗿𝗶𝗱 - Runs on a standard 20 lb. liquid propane tank and is equipped with an electronic ignition powered by two D-cell batteries. Can be used in a variety of scenarios: while you're camping, RVing, hunting, hanging poolside, washing your pets or horses, cleaning your vehicle, or even in your tiny home, greenhouse, or cabin house.
Top 23
Best for Gas Powered
Best Gas Water Heaters
Best for 30 Gallon
Best for Tankless
Best for Rheem
Best for 5 GPM
Best for 6 GPM
Best for 7 GPM
Best for 8 GPM
Ranein Natural Gas Tankless Water Heater, Indoor Max 8.5 GPM, 190,000 BTU Instant Hot Water Heater
Ranein
RH19K-NG
15.08 x 15.08 x 24.25 Inches
42.0 pounds
Ratings for Ranein (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| Ranein Store | - | ❌ | ❌ | ❌ |
| Amazon Resale | - | ❌ | ❌ | ❌ |
Features
Fans Placed Underneath: It will be more secure in terms of safety, and no smoke backflow will occur. The blower has large power and can automatically adjust the rotating speed according to the change of external wind pressure and the change of water temperature to provide sufficient oxygen for gas combustion, ensuring full combustion and safer use. Low noise and longer service life.
No Waiting Required: Unlike traditional tank water heaters, tankless water heaters eliminate the need for a 30-minute preheating wait time, allowing you to have unlimited hot water on demand.
Top 24
Best for Whole House
Best Gas Water Heaters
Best for 30 Gallon
Best for 40 Gallon
Best for 50 Gallon
Best for 60 Gallon
Best for 75 Gallon
Best for Tankless
Best for Takagi
Best for 2 GPM
Best for 7 GPM
MIZUDO Natural Gas Tankless Water Heater, Indoor or Outdoor Convertible Installation, Max 5.1 GPM 120,000 BTU, WiFi&APP Control CSA Certified for Large Families Whole House, GEN 3
MIZUDO
FDG-CS120AW-NG
14.56 x 14.56 x 22.83 inches
Ratings for MIZUDO (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| Mizudo Home Comfort Direct | - | ❌ | ❌ | ❌ |
Features
[Flexible Indoor&Outdoor Installation Solution]: Mizudo innovative natural gas tankless water heater indoor offers versatile installation options to meet various home configurations. Convert from indoor to outdoor use with accessory kits (Purchase Required), providing homeowners unprecedented flexibility for space utilization
[Smart WiFi and App Control]: Manage your tankless water heater gas remotely through the dedicated mobile application. Adjust temperature settings, monitor energy usage, and receive maintenance notifications from anywhere
Top 25
Best for Rheem
Best for Rinnai
Best for EcoSmart
Best for 2 GPM
Best for 3 GPM
Best for 6 GPM
Best for 9 GPM
Best for 12 GPM
Best for 14 GPM
Westinghouse 14kW Tankless Water Heater Electric 240V, Wifi, ETL, Gray
Westinghouse
9.56 x 9.56 x 12.59 Inches
Ratings for Westinghouse (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| Westinghouse Home Comfort Direct | - | ❌ | ❌ | ❌ |
Features
【Dedicated Circuit Requirements & Installation】This Westinghouse tankless water heater electric requires a dedicated 60A double-pole breaker and 6 AWG wire at 240V for stable, safe operation. With 1/2" NPT connections and a compact wall-mountable design at just 12.59"H x 9.56"W x 3.28"D that takes zero floor space, this Westinghouse electric tankless water heater offers quick, hassle-free installation—whether new build or replacement, just as you'd expect from a genuine Westinghouse tankless water heater.
【3s Instant Heating& Strong GPM Output】This Westinghouse electric tankless water heater 240v delivers hot water in just 3 seconds with 98% thermal efficiency. The minimum start-up flow rate is 0.53 GPM.When inlet temperature is 62°F and outlet is set to 105°F, flow reaches 3.4 GPM—supporting 2 water points simultaneously. This on demand water heater brings endless instant hot water to your daily routine. That's the reliable performance you expect from a 14kW Westinghouse tankless water heater electric.
MIZUDO Tankless Water Heater Propane, Indoor or Outdoor Convertible Installation, Max 5.1 GPM 120,000 BTU, WiFi&APP Control CSA Certified for Large Families Whole House, GEN 3
MIZUDO
FDG-CS120AW-LP
14.56 x 14.56 x 22.83 inches
Ratings for MIZUDO (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| Mizudo Home Comfort Direct | - | ❌ | ❌ | ❌ |
Features
[Flexible Indoor&Outdoor Installation Solution]: Mizudo innovative propane tankless water heater offers versatile installation options to meet various home configurations. Convert from indoor to outdoor use with accessory kits (Purchase Required), providing homeowners unprecedented flexibility for space utilization
[Smart WiFi and App Control]: Manage your tankless water heater propane remotely through the dedicated mobile application. Adjust temperature settings, monitor energy usage, and receive maintenance notifications from anywhere
Top 27
Best for Rheem
Best for Rheem
Best for 50 Gallon
Best for 75 Gallon
Best for Rheem
Best for AO Smith
Best for 3 GPM
Rheem RRTGH84DVLN3701171 Rheem RTGH Series 8.4 GPM 157,000 BTU 120 Volt Residential Indoor Natural Gas Tankless Water Heater Stainless Steel
Rheem
RTGH-84DVLN-3
9.8 x 17.7 x 23.7 inches
59.88 pounds
Super High Efficiency
Ratings for Rheem (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| MTL Retailers | - | ❌ | ❌ | ❌ |
| Amazon.com | - | ❌ | ❌ | ❌ |
Features
Flow rate of 0.4 - 8.4 GPM
Available temperature settings range from 100 to 140F (default setting of 120F)
Top 28
Best for NG
Best for 30 Gallon
Best for 50 Gallon
Best for 75 Gallon
Best for Tankless
Best for Noritz
Westinghouse Smart Outdoor Tankless Water Heater Gas, 8.1 GPM 180,000 BTU Natural Gas Tankless Water Heater Whole House, ±1°F Temp Stability, Non-Condensing High Efficiency for 3-5 Fixtures, CSA
Westinghouse
HS180A0G-NG
17.1 x 17.1 x 26.8 Inches
42.0 Pounds
Ratings for Westinghouse (CPR Score)
| Seller | CPR Rank | Amazon Fulfilled | Prime | Free Shipping |
|---|---|---|---|---|
| Westinghouse Home Comfort Direct | - | ❌ | ❌ | ❌ |
Features
【Endless Hot Water for the Whole Home】Designed for outdoor installation, this natural gas tankless water heater delivers up to 8.1 GPM and 180,000 BTU of powerful on-demand performance. Comfortably supports 3–5 fixtures simultaneously, including showers, sinks, dishwashers, and laundry appliances without running out of hot water.
【Precise ±1°F Temperature Stability】Advanced self-modulating technology automatically adjusts gas and water flow to maintain consistent water temperature within ±1°F for a more stable and comfortable shower experience. Helps reduce cold bursts and sudden temperature fluctuations during everyday household use.
Top 10 4 GPM Tankless Water Heaters - Verified to Buy (October 2026)
- 1. CAMPLUX 2.64 GPM Portable Tankless Water Heater, Outdoor Water Heater...
- 2. Vancepic Natural Gas Tankless Water Heater Indoor,4.3 GPM | 3-4...
- 3. Tankless Water Heater 4.75 GPM Natural Gas Constant Hot Water
- 4. 27kW Tankless Water Heater Electric, NOVIEEX 240V 3s Instant Hot...
- 5. Ranein Propane Gas Tankless Water Heater, 5.3 GPM, 130,000 BTU,...
- 6. ThermoMate 98,500 Propane Tankless Water Heater, Up to 4 GPM,...
- 7. Novieex Propane Gas Tankless Water Heater Up to 4.3 GPM...
- 8. Rheem 11kW 240V Tankless Electric Water Heater
- 9. 18kW Tankless Water Heater Electric 240V WINTEMP, On Demand Instant...
- 10. WINTEMP 36kW Tankless Electric Water Heater 240V, Instant On-Demand Endless...
Top 10 4 GPM Tankless Water Heaters Brands on Amazon
Here is the list of top-rated brands that were evaluated by CherryPicks.
- CAMPLUX ENJOY OUTDOOR LIFE
- VancEpic
- Amzgachfktch
- NOVIEEX
- Ranein
- thermomate
- Rheem
- WINTEMP
- FOGATTI
- APUS
Related 4 GPM Tankless Water Heaters Guides
For more personalized 4 GPM Tankless Water Heaters guides, Check those pages,
GPM
Top 10 4 GPM Tankless Water Heaters Sellers: CPR Seller Rank List
CPR sellers rank is based on CherryPicks-AI bestselling ranking system that helps us analyze each seller's sales trends. The List of top seller ranks is our in-house data, essential for our product ranking to help you make the right shopping choice.
- 1. Woot : 266,742 Yearly Feedback , Avg. Ratings 4.8
- 2. Camplux : 2,742 Yearly Feedback , Avg. Ratings 4.7
- 3. Plumber's Paradise : 2,222 Yearly Feedback , Avg. Ratings 4.8
- 4. Gasland : 1,802 Yearly Feedback , Avg. Ratings 4.6
- 5. MTL Retailers : 499 Yearly Feedback , Avg. Ratings 4.1
- 6. Mizudo Home Comfort Direct : 404 Yearly Feedback , Avg. Ratings 4.7
- 7. Amazon.com : 386 Yearly Feedback , Avg. Ratings 4.7
- 8. ThermoMate Official : 375 Yearly Feedback , Avg. Ratings 4.7
- 9. Westinghouse Home Comfort Direct : 268 Yearly Feedback , Avg. Ratings 4.8
- 10. AXY Co : 172 Yearly Feedback , Avg. Ratings 4.9
| Rank | Name | Yearly Feedbacks | Avg. Ratings |
|---|---|---|---|
| 🥇 | Woot | 266,742 | 4.8 |
| 🥈 | Camplux | 2,742 | 4.7 |
| 🥉 | Plumber's Paradise | 2,222 | 4.8 |
| 4 | Gasland | 1,802 | 4.6 |
| 5 | MTL Retailers | 499 | 4.1 |
| 6 | Mizudo Home Comfort Direct | 404 | 4.7 |
| 7 | Amazon.com | 386 | 4.7 |
| 8 | ThermoMate Official | 375 | 4.7 |
| 9 | Westinghouse Home Comfort Direct | 268 | 4.8 |
| 10 | AXY Co | 172 | 4.9 |
[Get] 4 GPM Tankless Water Heaters Deals (✅Exclusively for Prime)
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Why Should You Trust Us?
Now hundreds and thousands of Rough Plumbing supplies are available on Amazon, Picking the right one is not easy, and that may take a lot of your time, Right? and What is the best 4 GPM Tankless Water Heaters to buy for new October 2026?
CherryPicks’s Methodology for Evaluating 4 GPM Tankless Water Heaters
We developed the CherryRatings-AI system to identify and score reviews and the CherryPicks-AI ranking system that uses TensorFlow framework to generate the best list, It will help us evaluate Rough Plumbing items that sell on Amazon. The score of items is based on over ten parameters such as analyzing customer review content, product reviewing rating statistics, brand reputation evaluation, comparing product price with features, etc, You can visit How We Rank to learn more in detail.
We collected and analyzed 306 of 4 GPM Tankless Water Heaters reviews based on our selection criteria. It helped us shortlist the top qualified and rated 4 GPM Tankless Water Heaters for Rough Plumbing, We found that most customers choose 4 GPM Tankless Water Heaters with an average price of $414.71, and the top brands are Westinghouse, CAMPLUX ENJOY OUTDOOR LIFE, GASLAND, Rheem, thermomate And FOGATTI.
Then our expert-level editors reviewed all those quality items and selected the top 28 4 GPM Tankless Water Heaters for you, We have researched hundreds of sellers and picked the top sellers for Rough Plumbing, including Amazon Resale, Woot, Camplux, Plumber's Paradise, Gasland, MTL Retailers, Mizudo Home Comfort Direct, Amazon.com, ThermoMate Official, Westinghouse Home Comfort Direct, AXY Co And Trena's Liquidation LLC. The CAMPLUX 2.64 GPM Portable Tankless Water Heater... are available for purchase right now, and The seller of #1 rank product has received honest feedback from 1,107 consumers with an average rating of 4.2.
We've helped a lot of satisfied users get the right Tools & Home Improvement product based on their needs, and save lots of time for them to pick 4 GPM Tankless Water Heaters to buy.
Sandy Armstrong is a sit-at-home mom that has used a good number of home appliances — some were good, others average, while some were terribly bad and a waste of money. She is here to help you avoid wasting your money by providing you with honest reviews on appliances.