Search  for anything...
MIZUDO

Natural Gas Tankless Water Heater, MIZUDO 4.0 GPM, 90,000 BTU Indoor Installation Instant Hot Water Heater, Gen 2

    • Based on 43 reviews
Condition: New
Checking for product changes
$399.00 Why this price?
Save $59.00 was $458.00

Buy Now, Pay Later

As low as / mo
  • – Up to 36-month term if approved
  • – No impact on credit
  • – Instant approval decision
  • – Secure and straightforward checkout

Ready to go? Add this product to your cart and select a plan during checkout. Payment plans are offered through our trusted finance partners Klarna, PayTomorrow, Affirm, Afterpay, Apple Pay, and PayPal. No-credit-needed leasing options through Acima may also be available at checkout.

Learn more about financing & leasing here.

Selected Option

Free shipping on this product

30-day refund/replacement

To qualify for a full refund, items must be returned in their original, unused condition. If an item is returned in a used, damaged, or materially different state, you may be granted a partial refund.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

Availability: Only 10 left in stock, order soon!
Fulfilled by Amazon
Arrives Saturday, Mar 15
Order within 10 hours and 31 minutes
Available payment plans shown during checkout

Material Type: 4.0GPM | 90,000BTU


Style: Natural Gas


Features

  • Quality Certification: It has passed CSA certification and has protection functions such as overheating protection and accidental flameout protection. It meets national safety standards and protects the safety of you and your family in many aspects.
  • Endless Hot Water: No need to wait for the water tank to heat up, it provides endless hot water 24 hours a day, allowing you and your family to use a steady stream of hot water at multiple locations at any time.
  • Precise Temperature Control: The internal movement can keenly sense changes in water temperature and intelligently adjust the water temperature to ensure that the temperature difference is within 1F.
  • Quality Material: The built-in oxygen-free copper water tank has excellent thermal conductivity and anti-corrosion effects, allowing the water heater to have a longer service life and achieve durability.
  • Product Information: Dimensions are H 26.2'' x W 17.1'' x D 7.3''. Compared with tank water heaters, it can save more than 50% of space. The interface is universal 3/4"NPT, which is easy to install.

Brand: MIZUDO


Product Dimensions: 16.3"W x 25"H


Special Feature: Comfortech 2nd Generation, Built-in Water Proportional Valve 2.0, 2&5 Years Warranty, 24/7 Customer Service, CSA Certified See more


Color: White


Wattage: 20 watts


Brand: ‎MIZUDO


Product Dimensions: ‎16.3"W x 25"H


Special Feature: ‎Comfortech 2nd Generation, Built-in Water Proportional Valve 2.0, 2&5 Years Warranty, 24/7 Customer Service, CSA Certified


Color: ‎White


Wattage: ‎20 watts


Voltage: ‎120 Volts (AC)


Maximum Flow Rate: ‎4 Gallons Per Minute


Heat Output: ‎90000 BTU per Hour per Foot per Degree Fahrenheit


Efficiency: ‎High


Mounting Type: ‎Wall


Is Electric: ‎No


Manufacturer: ‎Mizudo


Item Depth: ‎22.76 inches


Item Weight: ‎28.8 pounds


Item model number: ‎FDG-CS90AG-NG


Item Package Quantity: ‎1


Special Features: ‎Comfortech 2nd Generation, Built-in Water Proportional Valve 2.0, 2&5 Years Warranty, 24/7 Customer Service, CSA Certified


Included Components: ‎‎Gas Water Hetaer x 1, Manual x 1, Perforated Paper x 1, Assembly Kit x 1, Warranty Card x 1


Batteries Included?: ‎No


Batteries Required?: ‎No


Date First Available: January 13, 2024


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Mar 15

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
  • PayTomorrow Financing
  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Similar Products

Top Amazon Reviews

    • Great heater for the money
Material Type: 5.1GPM | 120,000BTU Style: Propane
Review Image by Jeffz Jeffz
I installed this in the cabin we live in about a month ago and so far it's been working well for us. The distance from the heater to the various taps is fairly short and there is a bit of a lag getting hot water to the outlets,but I believe that is more of a result of the "water saving" fixtures we are stuck with these days and their flow restrictive nature. Water temp fluctuations have been minimal. Though we have noticed some due to the lower temp of the incoming water to the heater after the water has run for a period of time. We have very cold water from our well. The unit is a little noisy,but that is far from our concerns. My only real concern is the water heater cycling when running the washing machine when set to a warm wash temperature. It runs for such a short period that the water doesn't really get an opportunity to heat and I feel like the rapid cycling is probably not good for the heater. I feel this is more of an issue with the washer than the heater. Our solution was to run the washer on a hot setting and reduce the temperature on the water heater. Right now we just have a whole house filter installed in the inlet. We did have a Water Drop scale inhibitor installed,but it leaked and had to return it to Amazon for a replacement. Definitely on the homestead priority list as we have very hard water. All in all we have been pretty happy with the heater. Super easy install except for cutting a hole in the logs for the vent. ... show more
Reviewed in the United States on May 23, 2024 by Jeffz Jeffz
    • Excellent Heater
Material Type: 4.0GPM | 90,000BTU Style: Propane
We installed this water heater for our tiny house 5 months ago and it has been wonderful. The water gets hot really quickly, and can get REALLY hot. I actually had to turn down the max heat temp. because it would get too hot! It also stays hot, though sometimes struggles to maintain the exact same temperature, but it never goes cold (and for this price it is working astonishingly well). Our shower is outside so hot water is crucial in December. Seems efficient, too, we haven’t yet had to refill our 100 gallon propane tank in the entire 5 months we’ve been using it. ... show more
Reviewed in the United States on December 16, 2024 by Anna Young
    • Good product
Material Type: 5.1GPM | 120,000BTU Style: Natural Gas
The first one that I ordered had some electrical defects when I hooked it up. The system continued to beep on and off constantly and would not work. I filed for a replacement through Amazon and it was a good interaction. I received a replacement model which works perfect!! It's quiet and heats water in seconds.. I'd buy again! ... show more
Reviewed in the United States on December 20, 2024 by Brett
    • Works Great!
Material Type: 4.0GPM | 90,000BTU Style: Natural Gas
Review Image by Jordan F. Jordan F.
I have a small 1200ft house with just my fiancé and I. This works great for our needs! Do research on the install as it’s not your normal water heater connections. I placed a larger 4” metal dryer vent hood through the exterior wall then routed the smaller vent pipe for the unit through it (vent pipe is smaller, 3”, so it doesn’t touch the homes walls). Water pressure is great, heat is very good, the only caveat is if your turning on and off your water (say washing your face) it’ll have to shoot out the cold water from restarting before it gets back to hot. Overall great purchase as it also should save money from not having a lite water heater 24/7. If you have hard water (I don’t) then maybe install a filter in line or flush your unit once a year with vinegar. ... show more
Reviewed in the United States on November 20, 2024 by Jordan F. Jordan F.
    • Do Not Purchase This!
Material Type: 4.0GPM | 90,000BTU Style: Natural Gas
Not working and no repair parts available. Waste of money. Transistor on mother board burned out and can not find replacement part. Had two service people look extensively from manufacturers company. So sorry we actually purchased two of these units, one for my daughter's home and one for our own home. Hers lasted almost 5 months. I'm afraid now to install mine. ... show more
Reviewed in the United States on December 18, 2024 by Janet M. Albritton
    • Works well
Material Type: 5.1GPM | 120,000BTU Style: Natural Gas
The heater is easy to install. Heat up water instantly and so far is working well without any problem.
Reviewed in the United States on January 8, 2025 by TL
    • Great workmanship
Material Type: 4.0GPM | 90,000BTU Style: Propane
I installed a 5.1 gpm in my RV. Couldn’t be happier. This was #2. As the first one had an issue. Amazon took it back and sent a replacement the next day. Works perfectly. Customer service at Mizudo was extremely helpful and friendly. Good choice to make!
Reviewed in the United States on July 28, 2024 by Ira A.
    • Saves a fortune
Material Type: 4.0GPM | 90,000BTU Style: Natural Gas
Plenty of hot water for a small household and so inexpensive.
Reviewed in the United States on October 3, 2024 by Andrew Yates

Can't find a product?

Find it on Amazon first, then paste the link below.