INSTAHEAT ULTRA
35K BTU RV Propane Furnace
$739.99
$1,299.99
Save $560.00
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Stronger ducted heat for colder RV travel.
InstaHeat 35K delivers four heating levels from 17K to 35K BTU through a central duct system. Rapid, Standard and Sleep modes, 320 CFM airflow and a 40 dB sleep setting give owners more control over recovery time and overnight comfort.
View all features ↓Best for larger compatible ducted RVs and colder trips that need the highest furnace output in this range.
35,000 BTUMaximum propane heating output
4 heat levels17K / 25K / 30K / 35K
320 CFMAirflow for central RV ducting
40 dBSleep-mode sound
Secure checkout
More options available at checkout
30-day returns
Free contiguous U.S. shipping
1-year warranty
Choose your InstaHeat furnace
CURRENT MODEL
InstaHeat 35K
35K BTU · 320 CFM
Choose 35K whenA larger compatible ducted RV and colder travel require the highest output in the range.
InstaHeat 30K
30K BTU · 260 CFM
Choose 30K whenA compatible mid-size RV needs balanced ducted heating recovery.
InstaHeat 25K
25K BTU · 240 CFM
Choose 25K whenA smaller compatible RV and lower calculated heat load make 25K the right size.
Fit and installation
- Furnace dimensions
- 17.7 W × 7.8 H × 20.1 D in
- Power supply
- 12V DC
- Duct outlet
- 4-in round
- Duct connections
- 7 openings
- Mounting
- Horizontal / vertical
- Heating system
- Central ducted
- Size
- 20.1 × 17.7 × 7.8 in
- Weight
- 27.6 lbs / 12.5 kg
Confirm cabinet space, return-air area, duct count, propane connection, exterior access and exhaust location. Non-horizontal mounting requires the approved bracket.
What’s included
- ✓FurnaceInstaHeat 35K propane heating unit
- ✓ControllerSmart wired controller
- ✓Access configurationSelected door option
- ✓Product documentationInstallation and operation manual
- ✓Package hardwareParts shown for the selected variant
Ducting, propane-line materials and vertical-mount brackets may need to be ordered separately.
Specifications
- Maximum heat output
- 35,000 BTU
- Heating levels
- 17K / 25K / 30K / 35K
- Operating modes
- Rapid / Standard / Sleep
- Airflow
- 320 CFM
- Sleep-mode sound
- 40 dB
- Electrical supply
- 12V DC
- Rated input
- 120W / 10A
- Duct outlet size
- 4 in round
- Fuel
- LP propane
Quick answers
Can it be installed vertically?
Yes. Horizontal or vertical mounting is supported when the approved bracket and manual clearances are used.
Will it work with in-floor ducts?
It can work with compatible central ducting when static-pressure and airflow requirements are met.
What door should I choose?
Select the option that matches the installation plan and exterior access arrangement.
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Complete a larger RV comfort system with rooftop cooling and hot water matched to the installation.
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Add 18K cooling and 16K heat-pump output with ducted or non-ducted options matched to the RV roof and 115V supply.
Check roof fit and configuration
For common tank-water-heater replacement openings
InstaShower Ultra
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View door and installation fit
InstaHeat 35K
Checkout code
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$739.99
$1,299.99
Save $560.00
HIGHER-OUTPUT DUCTED HEAT
Recover fast, then settle in quietly
InstaHeat 35K provides four heating levels from 17K to 35K BTU, 320 CFM airflow and a 40 dB sleep setting. It is built for larger RVs and colder travel where one fixed output forces a compromise between recovery and overnight comfort.
35,000 BTUMaximum heating output
4 heat levels17K / 25K / 30K / 35K
320 CFMCentral-duct airflow
40 dBSleep-mode sound
Use only the heat the cabin needs
The four output levels and three operating modes give the furnace more room to respond to changing cabin demand.
RAPID RECOVERY
Recover quickly with 35K output
Higher maximum output shortens recovery when the heat load, ductwork and propane system are all sized correctly.
FOUR HEAT LEVELS
Step down instead of always running high
The 17K, 25K, 30K and 35K levels help the system match changing cabin demand more closely.
QUIETER NIGHT OPERATION
Maintain comfort in 40 dB sleep mode
Use the lower-output mode to maintain comfort overnight instead of repeatedly calling for maximum recovery.
BUILT-IN PROTECTION
Monitor ignition, flame and airflow
Correct propane, exhaust, return air and 12V installation remain essential to safe heating.
WHO NEEDS 35K?
35K output for larger central-duct RV systems
Four heat levels and up to 320 CFM give larger RVs more recovery and control in colder travel.
A strong fit for larger rigs and colder routes
Choose it when faster recovery and more heat reserve are genuinely needed.
Choose 30K for a more balanced mid-size replacement
The 30K model provides a balanced option for moderate heat loads and lower duct airflow.
Match output to return air and duct capacity
A restricted duct system can undermine performance and create avoidable furnace problems.
Complete 35K furnace-system compatibility
The 35K platform pairs with compatible return air, supply ducts, exhaust, 12V power and LP propane.
FIT AT A GLANCE
Built for larger central-duct RV heating systems.
The four-stage furnace delivers up to 35K BTU and 320 CFM through a compatible return-air and supply-duct layout.
- Heating levels
- 17K / 25K / 30K / 35K
- Airflow
- 320 CFM
- Power supply
- 12V DC
- Rated current
- 10A
- Duct static pressure
- 0.10 in WC
Horizontal or vertical installation is supported; vertical mounting uses the specified bracket and guide clearances.
Compatible Accessories
Match output to the RV and ducts
Compare output with the furnace being replaced and the capacity of the existing duct system.
InstaHeat 35K
For larger rigs, colder travel and owners who need fast recovery plus lower overnight levels.
- Maximum heat
- 35K BTU
- Airflow
- 320 CFM
- Heat levels
- 4
InstaHeat 30K
For many travel trailers and fifth wheels with moderate heat loads.
- Maximum heat
- 30K BTU
- Airflow
- 260 CFM
- Heat levels
- Standard output
InstaHeat 25K
For lighter heat loads and smaller ducted interiors.
- Maximum heat
- 25K BTU
- Airflow
- 240 CFM
- Best for
- Smaller cabins
See installation and heating in action
Cabinet work, vertical mounting and real heating operation in three practical videos.
▶
FURNACE REPLACEMENT
See a complete furnace replacement
Cabinet preparation, ducting, propane, 12V wiring and startup.
▶
VERTICAL INSTALLATION
See how vertical mounting is supported
Bracket placement, clearances and the details that change with orientation.
▶
OWNER REVIEW
See heating operation after installation
A practical look at startup, airflow and cabin heat in an RV.
Quick answers about 35K output, ducts and installation
Clear guidance on heat load, duct capacity, cabinet fit and installation orientation.
Which RVs are a strong fit for 35K?
It is designed for larger RVs, colder routes and central duct systems sized to move up to 320 CFM.
Does it work with central RV ducting?
Yes. It distributes heat through compatible return-air and supply-duct systems.
Can it be installed vertically?
Yes. Use the specified bracket, clearances and orientation instructions in the installation guide.
What do the four heat levels change?
They let the furnace recover at higher output, then step down to maintain comfort more quietly and efficiently.
What does installation require?
A compatible cabinet, exhaust location, return-air area, supply ducts, 12V wiring and LP propane connection.
Ready for higher-output ducted heat?
Select the door option in the buy box. The installation guide is available for final furnace-fit planning.
This product is rated 4.9 of 5.0 stars.
It has received 34 reviews.
Overall rating: 4.885714 / 5 from 35 reviews.
AI Generated Review Summary
The Fogatti 35,000 BTU Quiet LP Gas Propane RV Furnace offers rapid warmth with adjustable power levels and heating modes. It features advanced temperature control, safety technology, and a quiet operation for comfortable sleep. Its durable design and reliable safety features make it a dependable choice for RV heating.
Summary topics
- Weather Protection (10%): Customers expressed appreciation for the waterproof and dustproof design, which ensures their furnace stays protected, no matter the weather or road conditions.
- Installation Simplicity (26%): Many customers brought up that the installation of the product was very simple and took just a few minutes.
- Door Durability (20%): A significant number of customers loved the door for their RV, praising its durability and ease of installation.
- Installation Ease (17%): Customers have mixed opinions about the unit, with some finding it nice and easy to install.
Review topics: [].
Review highlights
- "Installation was simple, and the material of the door feels good and sturdy." —
- "The waterproof and dustproof design is practical; my door can get wet or dusty." —
- "The door for my furnace was the perfect size; it fit in perfectly." —
Reviews
I m replacing
"I m replacing my old Atwood unit. Up grading the size and output. Need to make a few significant changes but honestly feel it will be a worthwhile and enjoyable choice. Will try to share another review when the project is completed and in use."
"Delivery great. Hadn’t opened yet."
The unit is very
"The unit is very nice; I wish they make it with a rotating duct ring in housing to make an easier installation with a longer cable or WiFi thermostat. Other than that; It s a Great product as the company is known for !!! Can I get a hat/shirt to promote lol"
Its a great furnace,
"It's a great furnace, it's both quieter and heats better then the Suburban it replaced. The only minus I can see it it's not possible to calibrate the thermostat. Mine is off -11 degrees and I have to take that into account when setting the temperature. Still better than having an anemic chainsaw heating your rig."
I am replacing an
"I am replacing an old Atwood rv furnace and have heard many good things about Fogatti furnaces. Better quality and better parts. Much better price. After talking with Fogatti, they did not have the exact match, which I will have to have, so I had to shop elsewhere. This review is to complement Fogatti on being honest with me and not trying to sell me something close that would require modifications to the unit or my camper. In Fogatti's words "We want you to be happy with your purchase. " Thank you Fogatti. Ken Shelton"
This is for the
"This is for the RF035 unit to replace a 35,000 BTU Attwood factory installed in our 2018 Thor Hurricane 31S. This is a long review. GREAT PRODUCT. Before purchasing I discussed with Fogatti if the RF035 was a direct replacement and found it is not a DIRECT replacement in the the Propane connection as at the bottom on the LHS looking from the outside of the RV and at the inside near the heating ducts connections. Also the dimensions were slightly different specifically, the RF035 was taller. After checking access to the existing furnace and sizes I purchased the RF035. The RF035 is well built and there are no sharp metal edges. After removing the old unit I checked the fitting of the RF035. I had to make another base support which which had to be 0. 75" lower because the extra height in order for the RF035 to clear the waste water pipe. I then bench tested the unit on a table next to the RV. Everything worked well and the controller is a great upgrade. I had to add 24" propane hose extension and built a new insert for the opening in the RV wall mainly to securely fit the new front cover door. I used the existing wiring for the thermostat; spliced the connections at the unit and at the old thermostat and installed the new Thermostat in the same area as the existing thermostat. . The RF035 is so much quieter"
GREAT PRODUCT! Was very
"GREAT PRODUCT! Was very easy to install. Replaced the old hard to find Atwood unit with this one. Went right in. Connected everything, ran through start up and it fired right up with no issues. LOVE FOGATTI!!"
Exactly as described. Installation
"Exactly as described. Installation went fairly well and the furnace works as expected. Arrived undamaged and well packaged and on time."
Very simple installation. Three
"Very simple installation. Three output settings, works great. Very impressed with heat output and overall function."
Hi, a little slow
"Hi, a little slow in my reply, but with two calls, A BIG HAMMER (LOL) it works great. Replacing a Suburban in a 2002 Newmar Kountry Star. Could not be more pleased. Simple instructions, but small space with big fingers. Just took my time, many coffee breaks and everything worked out. I am looking forward to my next RV that I could try out the tankless water heater. Have a Truma now, no need to change."