{"product_id":"dometic™-dfmdh35121-rv-furnace-35-000-btu-lp-gas-bottom-discharge-12v-dc","title":"Dometic™ DFMDH35121 RV Furnace – 35,000 BTU – LP Gas – Bottom Discharge – 12V DC","description":"\u003ch1\u003eDometic™ DFMDH35121 RV Furnace – 35,000 BTU – LP Gas – Bottom Discharge – 12V DC\u003c\/h1\u003e\n\u003cp\u003e\u003cstrong\u003eDFM Series | Hall Effect Sensor | Doorless Model | 2-Year Warranty\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eModel:\u003c\/strong\u003e DFMDH35121\u003cbr\u003e\u003cstrong\u003eSeries:\u003c\/strong\u003e DFM “H” Series\u003cbr\u003e\u003cstrong\u003eFuel Type:\u003c\/strong\u003e LP Gas (Propane)\u003cbr\u003e\u003cstrong\u003eBTU Output:\u003c\/strong\u003e 35,000 BTU\u003cbr\u003e\u003cstrong\u003eStage:\u003c\/strong\u003e Single Stage\u003cbr\u003e\u003cstrong\u003eVoltage:\u003c\/strong\u003e 12 Volt DC\u003cbr\u003e\u003cstrong\u003eDischarge Type:\u003c\/strong\u003e Bottom Discharge\u003cbr\u003e\u003cstrong\u003eGas Connection:\u003c\/strong\u003e Rear Gas Manifold\u003cbr\u003e\u003cstrong\u003eExterior Door:\u003c\/strong\u003e Not Required (Doorless Model)\u003cbr\u003e\u003cstrong\u003eThermostat Sold Separately\u003c\/strong\u003e\u003c\/p\u003e\n\u003chr\u003e\n\u003ch2\u003eProduct Overview\u003c\/h2\u003e\n\u003cp\u003eThe \u003cstrong\u003eDometic™ DFMDH35121\u003c\/strong\u003e is a high-output \u003cstrong\u003e35,000 BTU LP gas RV furnace\u003c\/strong\u003e designed for medium-sized heating applications where maximum flexibility and installation simplicity are required.\u003c\/p\u003e\n\u003cp\u003eThis model is part of the advanced \u003cstrong\u003eDFM “H” Series\u003c\/strong\u003e, featuring a modern \u003cstrong\u003eHall Effect airflow verification system\u003c\/strong\u003e that replaces the traditional mechanical sail switch. The Hall sensor electronically monitors blower motor rotation to confirm proper airflow before ignition — improving reliability and reducing common airflow-related service issues.\u003c\/p\u003e\n\u003cp\u003eUnlike standard furnace models, the DFMDH35121 is a \u003cstrong\u003edoorless configuration\u003c\/strong\u003e, meaning no exterior access door is required for installation. This eliminates the need to cut a large hole in the sidewall of your RV.\u003c\/p\u003e\n\u003cp\u003eThis makes the DFMDH35121 one of the easiest furnaces to install in:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eVan conversions\u003c\/li\u003e\n\u003cli\u003eSmall travel trailers\u003c\/li\u003e\n\u003cli\u003eTruck campers\u003c\/li\u003e\n\u003cli\u003eOverland builds\u003c\/li\u003e\n\u003cli\u003eTiny homes\u003c\/li\u003e\n\u003cli\u003eIce fishing houses\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e⚠ \u003cstrong\u003eImportant:\u003c\/strong\u003e Always measure your existing cut-out before ordering to ensure proper fitment.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch1\u003eKey Features\u003c\/h1\u003e\n\u003cul\u003e\n\u003cli\u003e35,000 BTU heating capacity\u003c\/li\u003e\n\u003cli\u003eLP gas (propane) operation\u003c\/li\u003e\n\u003cli\u003eSingle-stage heating performance\u003c\/li\u003e\n\u003cli\u003eBottom discharge airflow configuration\u003c\/li\u003e\n\u003cli\u003e12 Volt DC operation\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eHall Effect airflow verification (no mechanical sail switch)\u003c\/strong\u003e\u003c\/li\u003e\n\u003cli\u003eBuilt-In Soft Start technology\u003c\/li\u003e\n\u003cli\u003eRear gas manifold configuration\u003c\/li\u003e\n\u003cli\u003eDoorless design (no exterior access door required)\u003c\/li\u003e\n\u003cli\u003eFlexible installation orientation\u003c\/li\u003e\n\u003cli\u003eThermostat sold separately\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003e2-Year Limited Manufacturer Warranty\u003c\/strong\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch1\u003eSpecifications\u003c\/h1\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eModel:\u003c\/strong\u003e DFMDH35121\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSeries:\u003c\/strong\u003e DFM H Series\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBTU Rating:\u003c\/strong\u003e 35,000 BTU\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFuel Type:\u003c\/strong\u003e LP Gas\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHeating Stage:\u003c\/strong\u003e Single Stage\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVoltage:\u003c\/strong\u003e 12 Volt DC\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAirflow Configuration:\u003c\/strong\u003e Bottom Discharge\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGas Connection:\u003c\/strong\u003e Rear Manifold\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWidth:\u003c\/strong\u003e 16-1\/2 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHeight:\u003c\/strong\u003e 7 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDepth:\u003c\/strong\u003e 20 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAirflow Monitoring:\u003c\/strong\u003e Hall Effect Sensor\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSoft Start:\u003c\/strong\u003e Yes\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExterior Door Included:\u003c\/strong\u003e No (Doorless Model)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThermostat Included:\u003c\/strong\u003e No\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 2-Year Limited Manufacturer Warranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch1\u003eDoorless Installation – Pros \u0026amp; Cons\u003c\/h1\u003e\n\u003ch3\u003eBenefits\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eNo large exterior wall cut required\u003c\/li\u003e\n\u003cli\u003eCleaner RV exterior appearance\u003c\/li\u003e\n\u003cli\u003eGreater flexibility in mounting options\u003c\/li\u003e\n\u003cli\u003eEasier installation for custom builds\u003c\/li\u003e\n\u003cli\u003eIdeal for compact or specialty RV layouts\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003e⚠ Considerations\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eFurnace must be serviced from inside the RV\u003c\/li\u003e\n\u003cli\u003eNo exterior access panel for maintenance\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eFor many van and custom builds, avoiding a large exterior cut is a major installation advantage.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch1\u003eWhy Choose the DFM “H” Series?\u003c\/h1\u003e\n\u003cp\u003eTraditional RV furnaces use mechanical sail switches that can:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eStick or collect debris\u003c\/li\u003e\n\u003cli\u003eCause intermittent ignition failures\u003c\/li\u003e\n\u003cli\u003eRequire cleaning or replacement\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThe \u003cstrong\u003eHall Effect system\u003c\/strong\u003e in the DFMDH35121 electronically verifies airflow by monitoring motor rotation, resulting in:\u003c\/p\u003e\n\u003cp\u003e✔ Improved ignition reliability\u003cbr\u003e✔ Reduced maintenance\u003cbr\u003e✔ Better cold-weather performance\u003cbr\u003e✔ Fewer airflow-related faults\u003c\/p\u003e\n\u003cp\u003eCombined with Soft Start technology, it reduces startup surge and protects your RV’s 12V electrical system.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch1\u003eFrequently Asked Questions (FAQ)\u003c\/h1\u003e\n\u003cp\u003e\u003cstrong\u003eQ: What does the “H” in DFMDH mean?\u003c\/strong\u003e\u003cbr\u003eA: It indicates a Hall Effect airflow verification system rather than a mechanical sail switch.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: Does this furnace require an exterior access door?\u003c\/strong\u003e\u003cbr\u003eA: No. This is a doorless model.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: Where is the gas connection located?\u003c\/strong\u003e\u003cbr\u003eA: It uses a rear gas manifold configuration.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: Is this propane only?\u003c\/strong\u003e\u003cbr\u003eA: Yes, it operates on LP gas (propane).\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: Is a thermostat included?\u003c\/strong\u003e\u003cbr\u003eA: No. A compatible 12V furnace thermostat must be purchased separately.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: What warranty is included?\u003c\/strong\u003e\u003cbr\u003eA: This furnace includes a 2-year limited manufacturer warranty.\u003c\/p\u003e","brand":"RV Furnace Guys","offers":[{"title":"Default Title","offer_id":47857606623473,"sku":null,"price":1549.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0784\/4941\/0289\/files\/351211.png?v=1772400431","url":"https:\/\/www.rvfurnaceparts.com\/products\/dometic%e2%84%a2-dfmdh35121-rv-furnace-35-000-btu-lp-gas-bottom-discharge-12v-dc","provider":"RV Furnace Guys","version":"1.0","type":"link"}