Forimo 4.74 GPM Indoor Natural vs Forimo 16L Indoor Propane Tankless Water Heater: Spec Comparison
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You are looking at the forimo 4 74 gpm indoor natural vs 16l indoor propane tankless water heater comparison. Both units deliver instant hot water for indoor use in homes or cabins. They share stainless steel construction, digital displays, and similar safety features. The main difference lies in their fuel source and power output. One runs on natural gas with higher BTU capacity, while the other uses propane with a slightly lower flow rate. Choose based on your available gas line and hot water needs.
Key differences
| Aspect | Forimo 4.74 GPM Indoor Natural Gas Water Heater | Forimo 16L Indoor Propane Tankless Water Heater |
|---|---|---|
| Fuel Type | Natural Gas (LNG) | Propane (LPG) |
| Flow Rate | 4.74 GPM | 4.21 GPM |
| Power Output | 123,000 BTU/hr | 81,888 BTU/hr |
| Dimensions | 22 x 13.8 x 13.8 inches | 21.7 x 13.8 x 13.8 inches |
| Minimum Water Pressure | 0.2 MPa (29 PSI) | 3.6 PSI |
Which one should you choose?
Choose Forimo 4.74 GPM Indoor Natural Gas Water Heater if
- You have a natural gas line available for connection.
- You need a higher flow rate for multiple simultaneous uses.
- You prefer a unit with higher maximum power output.
Choose Forimo 16L Indoor Propane Tankless Water Heater if
- You rely on propane tanks for your heating needs.
- You have very low incoming water pressure (3.6 PSI).
- You want a slightly more compact vertical footprint.
Verdict: Select the natural gas model if you have a dedicated gas line and want faster hot water delivery. Choose the propane unit if you are using tanks or have low water pressure. Both provide efficient indoor heating for small spaces.
Flow, Fuel, and Venting Specs
Flow rate and output
You need to consider how much hot water each unit provides per minute. The Forimo 4.74 GPM Indoor Natural Gas Water Heater delivers 4.74 gallons per minute. This higher flow rate supports simultaneous use at multiple fixtures, such as a shower and a kitchen sink, without significant pressure drops. The Forimo 16L Indoor Propane Tankless Water Heater offers 4.21 gallons per minute. While still sufficient for most single-family homes, it provides slightly less volume. If you have a large household or high-demand appliances, the higher GPM of the natural gas model gives you more flexibility in usage.
Fuel type compatibility
The fuel source is a critical decision that determines which unit fits your home infrastructure. The Forimo 4.74 GPM Indoor Natural Gas Water Heater is designed exclusively for Natural Gas (LNG). It requires a connection to your existing natural gas line. The Forimo 16L Indoor Propane Tankless Water Heater uses Propane (LPG). This unit is suitable for homes with propane tanks or rural properties without natural gas lines. You must choose the model that matches your available fuel supply. Converting between natural gas and propane is not recommended or supported by the manufacturer specifications for these specific models.
Heating capacity and BTU
Power output affects how quickly water heats and how well it maintains temperature under load. The natural gas model features a maximum power output of 123,000 BTU per hour. This higher thermal input allows it to raise water temperature more aggressively, which is beneficial in colder climates or for larger units. The propane model has a maximum output of 81,888 BTU per hour. While this is adequate for standard indoor applications, it provides less raw heating power. If you live in an area with very cold incoming water temperatures, the higher BTU rating of the natural gas unit may offer more consistent performance.
Venting requirements
Installation involves specific venting needs that affect where you can place the unit. The Forimo 4.74 GPM Indoor Natural Gas Water Heater comes with a 6 cm (2.3 inch) diameter exhaust vent. This standard size requires a dedicated exhaust pipe to vent combustion gases outdoors safely. The Forimo 16L Indoor Propane Tankless Water Heater includes a 2.4 inch horizontal vent pipe. Both units require proper ventilation and smoke exhaust pipes for safe operation. You must ensure your home has the necessary ducting or wall penetration capabilities to accommodate the specific venting diameter and orientation required by your chosen model.
Physical dimensions and fit
Space constraints in your utility room or closet matter for installation planning. The natural gas model measures 22 inches in height, 13.8 inches in width, and 13.8 inches in length. The propane model is slightly shorter at 21.7 inches in height, with the same width and length of 13.8 inches. Both units are compact and save over 50% of the space compared to traditional tank water heaters. The difference in height is minimal, but if you have a tight vertical clearance, the propane model offers a slight advantage. Both are designed for indoor installation and feature a black finish.
Which Forimo tankless heater fits you
Natural gas users needing higher flow
This unit runs on natural gas and delivers 4.74 GPM. Its 123,000 BTU output supports simultaneous use at two or three fixtures. The minimum water pressure requirement is 0.2 MPa. You get steady temperature control with safety protections against overheating. The stainless steel body resists corrosion for long indoor use.
Propane users preferring lower pressure start
This model uses propane and outputs 4.21 GPM. It requires only 3.6 PSI water pressure to start, which helps if your supply is weak. The 81,888 BTU heater provides on-demand hot water. It features a digital display for temperature adjustments. The compact design fits indoor spaces like cabins or small apartments.
Buyers wanting maximum heat output
You should choose this option for its 123,000 BTU power rating. This higher output ensures faster heating and better performance during cold weather. The 4.74 GPM flow rate handles multiple taps easily. It includes an LED display for precise temperature setting. The built-in copper tank reduces heat loss effectively.
The products compared
Forimo 4.74 GPM Indoor Natural Gas Water Heater
Best for: Natural gas homes needing multi-point hot water
- Fuel Type
- Natural Gas
- Flow Rate
- 4.74 GPM
- BTU
- 123,000 BTU/hr
- Installation Location
- Indoor
- Temperature Control
- Fahrenheit digital display
- Dimensions
- 22 x 13.8 x 13.8 inches
View on Amazon: Forimo 4.74 GPM Indoor Natural Gas Water Heater Affiliate link
This Forimo indoor unit runs on natural gas and delivers 4.74 GPM at 123,000 BTU/hr. It features a stainless steel body with an oxygen-free copper heat exchanger for durability. The digital display lets you set precise temperatures in Fahrenheit. It requires a minimum water pressure of 0.2 MPa. This heater suits homes needing hot water for two to three fixtures at once.
Pros
- 4.74 GPM flow rate supports multiple fixtures
- 123,000 BTU/hr output for rapid heating
- Digital display for precise Fahrenheit temperature control
- Stainless steel construction with copper heat exchanger
Cons
- Indoor installation only
- Requires dedicated exhaust venting
- Higher water pressure minimum than some competitors
Good fit if
- You have a natural gas supply
- You need hot water for two to three points
- You want precise temperature control via a digital display
Skip if
- You only have propane access
- You need outdoor installation
- You have low water pressure below 0.2 MPa
Verdict: Forimo 18L Natural Gas 4.74 GPM fits households with natural gas lines that need reliable hot water for multiple bathrooms or kitchens simultaneously.
Forimo 16L Indoor Propane Tankless Water Heater
Best for: Indoor propane hot water needs
- Fuel Type
- Propane (LPG)
- Flow Rate
- 4.21 GPM
- BTU
- 81,888 BTU/hour
- Installation Location
- Indoor
- Temperature Control
- Fahrenheit digital display
- Dimensions
- 21.7 x 13.8 x 13.8 inches
View on Amazon: Forimo 16L Indoor Propane Tankless Water Heater Affiliate link
This Forimo unit delivers 4.21 GPM of hot water using propane gas. It features an 81,888 BTU/hour output and a built-in LED digital display for temperature control between 38℃ and 75℃. The stainless steel and copper construction supports indoor installation in homes or small cabins. It requires only 3.6 PSI water pressure and includes a 2.4-inch horizontal vent pipe for setup.
Pros
- Outputs 4.21 gallons per minute for simultaneous use
- 81,888 BTU/hour heating power
- LED digital display for precise temperature adjustment
- Low 3.6 PSI water pressure requirement
Cons
- Lower flow rate than the 4.74 GPM natural gas competitor
- Uses propane fuel instead of natural gas
- Includes only a 2.4-inch vent pipe, which may be insufficient for all installations
Good fit if
- You have a propane gas supply available
- You need a compact unit for indoor installation
- You want digital temperature control
Skip if
- You require a flow rate higher than 4.21 GPM
- You only have natural gas lines
- You need outdoor-rated durability
Verdict: Forimo 16L Propane Indoor Tankless Heater suits users with propane access who need reliable indoor hot water. It offers steady temperature control but falls short on flow compared to larger natural gas models.
Specifications side by side
| Spec | Forimo 4.74 GPM Indoor Natural Gas Water Heater | Forimo 16L Indoor Propane Tankless Water Heater |
|---|---|---|
| Fuel Type | Natural Gas | Propane (LPG) |
| Flow Rate | 4.74 GPM | 4.21 GPM |
| BTU | 123,000 BTU/hr | 81,888 BTU/hour |
| Installation Location | Indoor | Indoor |
| Temperature Control | Fahrenheit digital display | Fahrenheit digital display |
| Dimensions | 22 x 13.8 x 13.8 inches | 21.7 x 13.8 x 13.8 inches |
| Features | Digital Display | Digital Display |
| Weight | not stated | 21.9 pounds |
| Color | Black | Black(16L-Propane) |
| Model | HW-FM-18-LNG | CT1412-HWRSQ |
| Size | not stated | 16L |
Frequently asked questions
Can I install the Forimo 16L propane heater indoors?
Yes, the Forimo 16L Indoor Propane Tankless Water Heater is designed for indoor installation. It features a compact black body measuring 13.8 inches wide and 21.7 inches high. This model suits users with propane access who need reliable hot water in confined spaces.
What is the flow rate of the Forimo natural gas unit?
The Forimo 4.74 GPM Indoor Natural Gas Water Heater delivers 4.74 gallons per minute. This higher flow rate supports simultaneous use at multiple fixtures. It is ideal for households with natural gas lines needing reliable hot water for several bathrooms or kitchens.
Do both heaters have digital displays?
Yes, both units include a digital display. This feature allows you to monitor and adjust the water temperature precisely. The Forimo 4.74 GPM Natural Gas model and the Forimo 16L Propane model both offer this control for steady temperature management.
Which model is better for multi-bathroom homes?
The Forimo 4.74 GPM Indoor Natural Gas Water Heater is better for multi-bathroom homes. It delivers 4.74 GPM, supporting simultaneous use at multiple fixtures. The propane model offers steady temperature control but falls short on flow compared to this larger natural gas unit.
How big is the Forimo 16L propane heater?
The Forimo 16L Indoor Propane Tankless Water Heater measures 13.8 inches in width and length. Its height is 21.7 inches. It weighs 21.9 pounds. This compact size fits well in indoor utility spaces or cabinets where space is limited.
What fuel types do these Forimo heaters use?
The first unit uses natural gas, while the second uses propane. The Forimo 4.74 GPM model is built for natural gas lines. The Forimo 16L model is designed for propane access. Both provide instant hot water for indoor residential use.
Is the Forimo natural gas heater suitable for cabins?
Yes, it is suitable for cabins with natural gas lines. The Forimo 4.74 GPM Indoor Natural Gas Water Heater provides reliable hot water for multiple points of use. Its indoor design and digital display make it a practical choice for remote or small dwellings.
What is the model number for the propane unit?
The model number for the propane unit is CT1412-HWRSQ. It is marketed as the Forimo 16L Indoor Propane Tankless Water Heater. This identifier helps you locate the correct replacement parts or technical documentation for your specific indoor installation needs.