The Suburban SF-35VHQ is one of the most capable propane furnaces available for RV use — a 35,000 BTU direct-duct unit designed for larger rigs that need serious heating performance. If you're replacing a worn-out furnace in a fifth wheel, large travel trailer, or Class A coach, or simply upgrading from an underpowered unit, the SF-35VHQ comes up consistently as one of the top recommendations.
But at $899.99, it sits at the higher end of the RV furnace market. Is the performance and build quality worth that investment? This review breaks it down.
Specs Overview
| Spec | Details |
|---|---|
| BTU Output | 35,000 BTU/hr |
| Ignition Type | Direct Spark Ignition (DSI) |
| Duct Outlet | 4-inch round duct |
| Input Voltage | 12V DC |
| Propane Consumption | ~0.38 lbs/hr at full output |
| Warranty | 2 years (Suburban) |
| Price | $899.99 at The RV Surplus |
Who Is This Furnace For?
The SF-35VHQ is built for larger RVs — fifth wheels, large travel trailers (29 feet and up), and Class A coaches — where a 25,000 or 30,000 BTU furnace simply can't keep pace in cold weather. If you've been underwhelmed by your current furnace's ability to heat the back bedroom or maintain temperature on sub-freezing nights, stepping up to 35,000 BTU typically solves that problem decisively.
It's also a strong choice for full-timers and cold-weather campers who put serious demands on their heating system season after season. Suburban's reputation for durability in high-use applications is well-established, and the SF-35VHQ is built to that standard.
Installation Experience
The SF-35VHQ installs in a standard RV furnace bay opening and uses a 4-inch round duct outlet — the same as most existing RV furnaces. For most owners replacing a previous unit, this is a straightforward swap: disconnect the gas line, disconnect the 12V wiring harness and DSI connections, unbolt the old unit, slide in the new one, and reconnect in reverse order.
The main variable is the physical footprint. If you're replacing a lower-BTU unit from a different manufacturer, confirm the SF-35VHQ's dimensions match your existing bay before ordering. Suburban furnaces are among the most dimensionally consistent in the industry, so cross-brand swaps are usually straightforward — but always measure first.
Most RV owners with basic mechanical experience complete the installation in 2–3 hours. First-timers should budget 3–4 hours and review our RV Furnace Sizing Guide to confirm this is the right BTU rating for their rig before starting.
Performance Testing
Heat Output
35,000 BTU delivers a noticeable step up from the 25,000–30,000 BTU units typically found in mid-size rigs. In a 35-foot fifth wheel, the SF-35VHQ brings the interior from a cold morning temperature to a comfortable setpoint significantly faster than a lower-BTU unit — and maintains it with shorter, more efficient run cycles rather than running continuously and barely keeping up.
Blower Performance
The multi-speed blower on the SF-35VHQ moves a high volume of air through the duct system, which helps distribute heat evenly throughout the coach. Slide-out areas and rear bedrooms — the zones most likely to feel under-heated with a smaller furnace — benefit noticeably from the higher airflow.
Noise Level
Like most propane RV furnaces, the SF-35VHQ isn't whisper-quiet — the blower and burner produce noticeable sound during operation. It's consistent and even, rather than intermittent or rattly, which most owners find acceptable. If you've previously lived with a failing furnace that was cycling poorly or making irregular noises, a properly functioning SF-35VHQ will feel significantly quieter by comparison.
Propane Efficiency
At approximately 0.38 lbs of propane per hour at full output, the SF-35VHQ is thriftier than its BTU rating might suggest. Because it heats efficiently and reaches setpoint quickly, it cycles off sooner — meaning total propane consumption over a cold night is often comparable to a smaller unit that runs longer to achieve the same result.
Pros and Cons
Pros
- Serious heating capacity: 35,000 BTU handles large floor plans and cold climates without struggling
- Suburban reliability: One of the most trusted furnace brands in the RV industry with wide parts availability
- Direct spark ignition: Reliable automatic ignition — no pilot light to babysit
- Standard fitment: Fits most existing furnace bays with a 4-inch duct outlet
- Strong blower output: Even heat distribution throughout larger coaches
- 2-year warranty: Backed by Suburban's standard coverage
Cons
- Price: At $899.99 it's a significant investment — but appropriate for what it delivers
- Overkill for smaller rigs: If your RV is under 28 feet, a lower-BTU unit is the better fit — see our BTU Sizing Guide
- Noise: Audible during operation, though consistent and non-disruptive for most owners
Who It's Best For
- You have a fifth wheel, large travel trailer (29 ft+), or Class A coach
- You camp in cold weather — consistently below 30°F overnight — and need reliable, powerful heat
- You're full-timing or camp frequently enough to justify a premium, durable unit
- Your current furnace is undersized and you're tired of cold spots and continuous run cycles
- You want a brand with excellent parts availability and a proven long-term track record
Final Verdict
The Suburban SF-35VHQ earns its price tag for the owner it's designed for. If you have a large rig, camp in serious cold, or want the most reliable furnace option on the market with the widest parts and service support, the SF-35VHQ delivers on all counts. The $899.99 price point reflects genuine quality — and the investment pays back over years of dependable cold-weather performance.
If you have a smaller rig or only camp in mild conditions, it's more furnace than you need. Use our RV Furnace BTU Sizing Guide to find the right unit for your specific rig and climate.
Frequently Asked Questions
What size RV is the Suburban SF-35VHQ designed for?
The SF-35VHQ is designed for larger RVs — typically fifth wheels, large travel trailers (29 feet and up), and Class A motorhomes. For rigs under 28 feet, a 25,000 or 30,000 BTU unit is usually the better fit.
Is the Suburban SF-35VHQ a direct replacement for other furnaces?
In most cases, yes. The SF-35VHQ uses a standard 4-inch duct outlet and fits most existing RV furnace bay openings. Confirm the physical dimensions match your existing bay before ordering, particularly if replacing a unit from a different manufacturer.
How long does it take to install the SF-35VHQ?
Most owners with basic mechanical experience complete the installation in 2–3 hours. Disconnect and reconnect the gas line, 12V wiring harness, and DSI connections, then secure the unit in the bay.
Does the Suburban SF-35VHQ come with a warranty?
Yes — Suburban covers the SF-35VHQ with a 2-year warranty.
How does the SF-35VHQ compare to the Dometic furnace lineup?
Both are reliable choices at the 35,000 BTU tier. Suburban has a longer track record in RV furnaces and typically has a slight edge on parts availability and technician familiarity. See our Suburban vs Dometic Furnace Comparison for a full breakdown.
Buy the Suburban SF-35VHQ at The RV Surplus
The SF-35VHQ is available at The RV Surplus for $899.99 with free shipping to the continental U.S.
Buy the Suburban SF-35VHQ at The RV Surplus →
Questions about whether this is the right furnace for your rig? Call or text us at 574-218-0549 and we'll help you confirm before you order. You can also check our RV Furnace Crossover Chart to see if your current model crosses over to the SF-35VHQ.