Dometic DFMDH35111 Medium RV Furnace | 35,000 BTU | LP | 12V | REQUIRES DOOR

Replace or upgrade your RV furnace with the Dometic DFMDH35111 Medium Furnace (Part 9610007792) — a 35,000 BTU LP gas furnace in a compact 16-1/2" × 7" × 20" footprint, built for RVs needing solid mid-range heating output in a tight install space. Available at The RV Surplus.

⭐ Key Specifications

⭐ Replaces DFMD35111

The DFMDH35111 is the current factory replacement for the older DFMD35111. If your parts list or furnace tag calls out DFMD35111, this is the correct supersession.

⚠️ Sold Separately — Order With Your Furnace

This furnace does NOT ship with a door or thermostat. You'll likely need to order one or more of these at the same time:

• 9610008133 — Thermostat
• 33011 — Furnace Door, Black
• 33057 — Furnace Door, White

Pick the door color that matches your coach exterior.

⭐ 3 Duct Collars Included

Three duct collars ship with the furnace — supports a 3-duct distribution layout out of the box. If your coach uses fewer ducts, cap the unused collars; if it uses more, source additional collars separately.

⭐ 12V DC Electrical — Know the Draw

At 11.1 amps / 132 watts, the DFMDH35111 pulls real current from your 12V battery. During extended cold-weather use with the furnace cycling frequently, this is often the single largest 12V load in the coach:

• Confirm battery capacity before extended boondocking in winter conditions
• A weak battery presents as a furnace that lights briefly and shuts off, or won't light at all
• Keep battery terminals clean and connections tight — voltage drop at the furnace reads as a bad board

⚠️ Before Calling It a Furnace Failure

If a new or existing furnace won't light, work through the basics first:

• LP gas supply — tank valve open, regulator working, lines bled of air
• 12V battery voltage AT the furnace — not just at the battery (long wire runs cause drop)
• Thermostat calling for heat — verify with a jumper at the furnace terminals if in doubt
• Return air blockage — the furnace needs airflow to prove the sail switch and allow ignition
• Exterior vents clear — wasps, spider webs, and debris block combustion and exhaust
• Listen for the sequence of events on a call for heat: fan starts → sail switch closes → gas valve opens → spark → flame → steady run. Where it stops narrows the fault.

⚠️ Install Considerations

• Furnace must be installed per Dometic's install manual — clearances, venting, and gas connections are safety critical
• Leak-test all LP connections with soapy water before firing the unit
• Verify proper exhaust clearances at the exterior vent — blocked exhaust creates CO risk
• If you're not experienced with LP gas appliances, have a qualified RV technician handle the install

What's Included

• (1) Dometic DFMDH35111 medium furnace
• (3) Duct collars

NOT included (sold separately):

• Furnace door (33011 black or 33057 white)
• Thermostat (9610008133)
• LP gas supply fittings and flex line
  

2-Year Manufacturer Warranty

Backed by Dometic's 2-year manufacturer warranty. Register with Dometic after install to activate.

Specifications

• Brand: Dometic
• Model: DFMDH35111
• Part Number: 9610007792
• Replaces: DFMD35121
• Series: Medium Furnace
• BTU Input: 35,000
• BTU Output: 25,840
• Fuel: LP (propane)
• Electrical: 12V DC
• Amp Draw: 11.1 A
• Watts: 132
• Dimensions: 16-1/2" W × 7" H × 20" D
• Duct Collars: 3 included
• Door: NOT included (order 33011 black or 33057 white separately)
• Thermostat: NOT included (order 9610008133 separately)
• Warranty: 2-year manufacturer