Martin Direct Vent Propane Wall Heater MDV20P – 20,000 BTU | Off‑Grid Wall‑Mount Heating Solution
Questions about this product
Questions about this product
What room size will each model handle?
538 Square Feet
Do they need electricity and will they run during an outage?
No power required. They use a standing pilot with a piezo ignitor and a mechanical control, so they keep heating with the lights out.
What clearances and mounting height do I need?
Sides 6 in. Above 24 in. From finished floor 7 in to the bottom of the heater. Rear clearance: MDV8 is 25/32 in, MDV12/MDV20 are 1-3/16 in. Use the included wall template. Keep the exterior vent cap at least 24 in from any outside intersecting wall.
What comes in the vent kit and what wall thicknesses are supported?
Vent kit includes: external air-intake tube with enamel hood, internal flue-gas tube, indoor and outdoor mounting plates, plus a wall thimble on MDV12 and MDV20, with threaded rod and adjusting nut. Approved wall thickness is 4-1/2 in to 12-5/8 in. Thicker walls aren’t supported by the manual.
Can I convert propane to natural gas, and what about high-elevation derate?
These units are not convertible. Order the model for your gas type. Above 2,000 ft, reduce input by 4 percent per 1,000 ft.
Delivery and shipping
Delivery and shipping
Orders are typically processed within 1 to 2 business days from the time of purchase, excluding holidays and weekends.
Shipping times and cost will vary depending on the product and your location.
On average:
Ontario and Quebec: 2 to 5 business days
Western Canada: 4 to 7 business days
Atlantic provinces: 4 to 8 business days
Northern or remote areas: Contact us to confirm
Martin Direct Vent Propane Wall Heater MDV20P – 20,000 BTU | Off‑Grid Wall‑Mount Heating Solution
Heat up your off-grid space with the Martin Direct Vent Propane Wall Heater MDV20P. The industry leading wall furnace keeps your living or work space warm with a direct vent wall heater that includes a built-in thermostat to monitor your heat dispersion. The direct vent gas heater produces safe, clean energy that’s economical and aesthetically pleasing. Installation is made easy by connecting the heater to a gas fitter to heat your living space effectively with low maintenance required.The sleek fireplace design is constructed from heavy-duty die-cast aluminum for durability and reliability. Its versatile front grill allows for better heat flow keeping the back of the unit at room temperature preventing the wall from becoming soiled. When installing wall thickness cannot be less than 4.5 inches and cannot exceed 12.63 inches.
Key Features
• 20,000 BTU Heating Power – Comfortably warms up to 538 ft²
• No Power Needed – Operates independently of electricity for off-grid reliability
• Direct Vent Safety – Clean, safe indoor air with external combustion and exhaust
• Built-In Thermostat – Automatically adjusts flame height for consistent room temperature
• Heavy-Duty Die-Cast Construction – Built to last in rugged environments
• Clean Wall Protection – Rear of the unit remains cool to avoid wall discoloration
• Simple Installation – Fits wall thicknesses from 4.5” to 12.63”
• Low Maintenance – Minimal upkeep with efficient, clean combustion
• Larger Footprint – 26” (W) x 8 1/4” (D) x 22 5/8” (H) | Weight: 47.4 lbs
• Color – Sleek silver and black
• Warranty – 1-Year Limited Manufacturer’s Warranty
Why Choose This Heater?
✔ Ideal for Off-Grid Living – Perfect for larger cabins, workshops, or off-grid homes that need more heat.
✔ Wall-Mounted Convenience – No bulky floor unit; just clean, efficient wall placement.
✔ Certified & Safe – CSA-certified for use in Canada and the US, with safety-focused direct venting.
✔ Set It & Forget It – With its built-in thermostat, the MDV20VP adjusts automatically to your desired comfort level.
To serve our customers across Canada, whether you're in a major city or completely off the grid, many of our products are shipped via freight delivery to ensure safe and efficient transport. Depending on your location and the item, you’ll have the option to pick up from a nearby warehouse terminal or request home delivery.
Free Terminal Pickup on Most Large Items
Most large items we sell, including appliances, solar kits, and other freight-shipped products, include free shipping to your closest warehouse terminal.
Your order will be delivered to the nearest terminal based on your location, where you can pick it up at your convenience.
Need it delivered to your home or cabin? We can set that up for you. There is a small additional fee for residential delivery.
Remote and Hard-to-Reach Locations
If you live in a remote area or outside standard freight zones, please contact us before placing your order.
Some rural locations may require additional charges or special delivery arrangements. We'll confirm everything with our freight partner before shipping.
Local Pickup Options Across Canada
We work with warehouse terminals in every province, so many of our products can be picked up locally to save on shipping costs.
Not all items are eligible, so if you're unsure at checkout, give us a call or send us an email and we'll confirm the best option for your area.
Shipping Times and Order Processing
Orders are typically processed within 1 to 3 business days from the time of purchase, excluding holidays and weekends.
Shipping times will vary depending on the product and your location. On average:
- Ontario and Quebec: 2 to 5 business days
- Western Canada: 4 to 7 business days
- Atlantic provinces: 4 to 8 business days
- Northern or remote areas: Contact us to confirm
We will provide tracking details when available once your order has shipped.
Receiving Freight Shipments
For large freight deliveries, you will receive a call from the carrier or your nearest terminal when your order is ready for pickup or delivery.
Important: Always inspect your shipment before signing any paperwork.
If the box or pallet is damaged:
- Do not sign the Bill of Lading (BOL) as "received in good condition"
- Instead, note the damage clearly on the BOL
- Or refuse the shipment if damage is significant
If no damage is recorded and the shipment is accepted, the freight carrier will consider it delivered in perfect condition. In that case, we cannot issue a refund or replacement. This is a strict freight carrier policy and applies to all deliveries.
Damaged or Missing Items
If there’s an issue with your shipment (whether it’s damage, missing parts, or anything unusual) please contact us within 48 hours of receiving the item. Be sure to include photos whenever possible, as these are often required to file a freight claim on your behalf. If the item was shipped to a terminal, it must be picked up within 48 hours or a $45/day storage fee will apply.
Payment & Security
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.