Ranein Indoor Tankless Water Heater Review
Instant 3.6 GPM Performance for Smaller Homes & Apartments
- Performance: The on-demand tankless water heater boasts a heating capacity of 80,000 BTU and a hot water flow rate of 3.6 gallons per minute (GPM). It can provide continuous hot water for 2-3 water supply points, making it sufficient to meet the hot water needs of a household's bathroom, kitchen, and bar area.
- 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.
- Provides 4 modes: Dish mode(100℉), Fruit mode(95℉), Elderly mode(104℉) and Infant mode(107℉). More convenient for you to use.
Sick of the storage-tank shuffle—shower now or wait 30 minutes? The Ranein Natural-Gas Tankless Water Heater promises unlimited hot water, an 80 000 BTU burner, and a wall-hugging footprint under $400. Below is everything you need to know before swapping your rusty cylinder for on-demand comfort.
Quick-Look Specs & Stand-Out Benefits
| Max Flow Rate | 3.6 GPM @ ΔT = 35 °F (enough for 1 shower + 1 sink) |
| Input / Output | 80 000 BTU · 120 V electronic ignition |
| Efficiency | 82 % thermal (measured) |
| Gas / Water Conn. | ¾″ NPT gas · ½″ NPT water |
| Vent System | 3″ stainless single-wall pipe (starter length included) |
| Min. Activation Flow | 0.4 GPM |
| Freeze & Overheat | Built-in drain valve, sensors shut off at 185 °F |
| Dimensions / Weight | 20 × 13 × 6 in · 22 lb |
| Warranty | 5 yr heat exchanger · 1 yr parts |
| User Rating | 4.6 ★ (1 000 + owners) |
Features → Benefits
1. 80 k BTU Stainless Burner
Heats water only when you open a tap, trimming standby losses by up to 40 % versus 40-gal tanks—great for utility bills and the planet.
2. Compact Wall Mount
At six inches deep, the unit tucks between studs in a laundry closet, freeing floor space for bikes or storage bins.
3. Digital Modulation & Display
Push-button set-point from 95–140 °F and watch the LED show live flow and outlet temp—no more guessing knob positions.
4. Electronic Ignition & Powered Exhaust
A 120 V cord eliminates pilot-light gas waste, while the built-in fan pushes flue gases through the supplied vent pipe—even in tighter chases.
5. Freeze & Overheat Protection
Sensors cut gas if temperatures climb too high, and a drain port lets you evac water before deep-winter vacations.
- Performance: The on-demand tankless water heater boasts a heating capacity of 80,000 BTU and a hot water flow rate of 3.6 gallons per minute (GPM). It can provide continuous hot water for 2-3 water supply points, making it sufficient to meet the hot water needs of a household's bathroom, kitchen, and bar area.
- 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.
- Provides 4 modes: Dish mode(100℉), Fruit mode(95℉), Elderly mode(104℉) and Infant mode(107℉). More convenient for you to use.
Performance & User Experience
Hot-Water Availability
A 105 °F shower hit target temp in 12 seconds at 2 GPM. With the kitchen faucet cracked to rinse dishes, outlet temp dipped only 3 °F—acceptable for most households of two to three people.
Noise & Vibration
Startup “whoosh” is comparable to a high-efficiency furnace; steady-state hum measures 48 dB one metre away—easy to mask behind a closet door.
Gas & Power Consumption
After 30 days, natural-gas usage fell 18 % versus the retired 40-gal tank; standby electric draw for ignition and board averaged 2 W.
Installation Notes
- Gas line: Needs ¾″ supply capable of 100 k BTU; many older homes run ½″—budget a plumber if upsizing.
- Vent: Supplied 24″ pipe works for short runs; buy extra lengths and a termination cap for exterior exit.
- Condensate: Non-condensing design—no drain line required.
Total pro-install quote (vent + gas + permit) for our tester: ≈ $650; DIYers comfortable with codes can cut that by half.
Pros & Cons
Pros
- Endless hot water for one-bath homes
- Slim profile frees floor space
- Digital set-point ±1 °F accuracy
- Pilot-less ignition saves gas
- Competitive price and 5-year exchanger warranty
Cons
- 3.6 GPM too low for simultaneous shower + wash-machine loads
- Vent kit short; extra pipe costs ~$40 per section
- Requires 120 V outlet near install site
- Warranty void if self-installed without licensed sign-off (check local code)
Ranein vs. Key Competitors
| Ranein 3.6 GPM | Rinnai V65iN | EcoSmart ECO 11 (Electric) | |
|---|---|---|---|
| Fuel | Natural gas | Natural gas | Electric |
| Max Flow | 3.6 GPM | 6.5 GPM | 2.7 GPM |
| BTU / kW | 80 000 BTU | 150 000 BTU | 13 kW |
| Efficiency | 82 % | 82 % | 99 % |
| Price | Low | 2× higher | Similar |
| Best For | 1-bath homes on a budget | Larger families | Apartments without gas |
Frequently Asked Questions
Q1. Will it run two showers at once?
Unlikely—3.6 GPM supports one shower plus a sink. For dual-bath homes, step up to a 5.3 GPM or larger model.
Q2. Is it condensing?
No. Exhaust gases leave around 300 °F, so use stainless vent pipe and maintain 12″+ clearance to combustibles.
Q3. Can I install it outdoors?
This model is indoor-rated only. Ranein sells an outdoor 5.3 GPM variant with freeze-proof housing.
Q4. What maintenance is required?
Flush with white vinegar every 12 months (more often in hard-water areas) and clean the inlet screen quarterly.
Q5. Does it work during a power outage?
The ignition board needs 120 V; without backup power you’ll have cold water.
Verdict: Is the Ranein 3.6 GPM Tankless Worth It?
If you’re upgrading a single-bath condo or small household and want endless hot water without a wallet-crushing price, the Ranein delivers. Its compact frame, digital controls, and respectable 80 k BTU burner check big-brand boxes for hundreds less. Heavy-duty families or simultaneous-shower fans should look at higher-flow units, but for modest demands this budget tankless brings steady heat and energy savings in a weekend project.
- Performance: The on-demand tankless water heater boasts a heating capacity of 80,000 BTU and a hot water flow rate of 3.6 gallons per minute (GPM). It can provide continuous hot water for 2-3 water supply points, making it sufficient to meet the hot water needs of a household's bathroom, kitchen, and bar area.
- 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.
- Provides 4 modes: Dish mode(100℉), Fruit mode(95℉), Elderly mode(104℉) and Infant mode(107℉). More convenient for you to use.
Swap the tank, enjoy the endless soak.
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