Expert Advice – Mr. Heater Big Maxx Garage Heaters

The Mr. Heater Big Maxx series has been a top selling garage heater for years. Designed for those cold winters, where work needs to get done, in places like : your garage, a company warehouse, barn or any other large space where warmth is essential, and appreciated, even if by an animal.

Below you’ll find the top selling (and highly rated) garage heaters :

Besides the Mr. Heater Big Maxx review, we also provide many tips and advice, as well as share garage heater installation videos to help you make a smart buying decision.

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Big Maxx Warranty : 10 year warranty on heat exchanger / 3 year warranty on parts and burner

📄 Read brochure or the Installation Manual : for the Big Maxx Heater Series : 50K BTU / 80K BTU / 125K BTU

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Intro | Mr. Heater Big Maxx

Garage Heaters | Reviews

Whether you have a barn that you work in or you have a fully kitted workshop or, like many DIY enthusiasts, you use the garage as a workshop for different projects, you’re probably spending a good deal of time there. Many people also use the garage as a home gym.

Workshop areas and garages are not the easiest to heat. These are large areas and are not always designed with creature comforts in mind. After all, if your garage is only used for parking cars, what’s the point of spending money on making it comfortable? So, when you’re using these areas in winter you need a special kind of heating. Garage heaters are designed to provide the type of heating that is required for this specific purpose.

Large Spaces — 125,000 BTU : Mr. Heater Big Maxx MHU125NG

Unlike in your home, you only spend time in your garage/workshop when needed. So you won’t be keeping it heated throughout the winter. You only want to use your garage heater when you’re actually there. This means that a garage heater needs to heat a large area rapidly and keep it warm while you’re in the area. For this reason, garage heaters are powerful radiation heaters that provide instant heat.

When it comes to garage heaters, the question of natural gas or propane vs electric is a common one. For a large open area that needs rapid heating, an outside fuel source (like propane or natural gas) is the most efficient. Electric is fine for space heaters used in small areas or central heating/AC units. In order to provide the BTUs needed for garage heating, burning a fuel is much more efficient.

Video | Installation & Operation | Mr. Big Heater Maxx

As the climate starts to turn and we head into winter, you may be looking at installing or replacing your existing garage heater. So we’ve set out to find some high-quality options at a reasonable price. After a good deal of research, the results come out in favor of the Mr. Heater Big Maxx range. We’ve considered what you’re looking for and this is firstly, the power to do the job and of course, durability. Even a cheap garage heater is going to cost a bit, so you need to know that you’re spending your money wisely. So this usually means not going for the cheapest deal but, at the same time, you don’t want to spend more than you have to.

Mr. Heater Big Maxx garage heaters offer a good combination of quality, features, and pricing and this is why we’ve chosen two of their most popular models as the focus of this review. These would be the Mr. Heater Big Maxx MHU50NG (50,000 BTU) and the more powerful MHU80NG (80,000 BTU). As a comparison, we’ll also look at the Modine HD60AS0111 Hot Dawg as a good alternative, though the price tag on this one might not be to everyone’s liking. In my humble opinion, you can’t beat the Mr. Heater Big Maxx range when it comes to value for the money.

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Mr. Heater Big Maxx MHU50NG (F260550) 

50,000 BTU

Perfect for : Residential Garages, Metal Buildings, Warehouses, Agricultural Building, Storage Buildings

Features:

• Easy outside access to thermostat and A/C terminals and gas connection
• Limited 3 year warranty on parts and burners
• Powered exhaust allows for vertical or horizontal venting
• Natural Gas to Liquid Propane conversion kit included
• 50,000 BTU per hour heats up to 1250 sq. ft.
• For use with natural gas
• Spark ignition features self-diagnostic control module
• Includes 2 angle brackets for ceiling mount
• Low Profile Design – Can be installed in low-ceiling buildings
• Minimum 8 ft clearance from floor to base of heater required
• 1/2″ gas connection
• Category 1 vertical, category 3 horizontal venting
• Natural Gas to Liquid Propane conversion kit included

✓ View or download the MANUAL for the Mr. Heater Big Maxx MHU80NG.

One of the benefits of using a propane or natural gas heater is that it doesn’t require a high current electrical supply and the Mr. Heater Big Maxx MHU50NG only requires a standard 115V AC supply. This is to power the fan and electric ignition spark.

This garage heater is designed for easy installation and access to the necessary connections. The Mr. Big Maxx MHU50NG has outside connections for the gas pipe and thermostat. You can choose whether to use it with natural gas or propane. If you want to use it with a propane gas cylinder, you’ll need a conversion kit.

Installation versatility is important for garage heaters, not everyone will be mounting it in the same position. To allow for this, the Mr. Big power exhaust can be adjusted for both vertical and horizontal venting. The unit also needs only 1” clearance, so it can be mounted right up against the ceiling with the vents directing the air downward for maximum heating efficiency. The brackets that are supplied with the unit, make for a simple installation job. With a weight of 63 lbs. and measuring 29.3” X 26.4” X 15.5”, it shouldn’t be difficult to find a convenient and safe position to mount the heater.

The heating power supplied by the Mr. Big Maxx MHU50NG is 50,000 BTU. This is sufficient heating for an area of about 1250 square feet. A powerful fan blows air across the heat exchange. It sucks the cold air in and disperses warm air into the surrounding area, providing an even spread of heating throughout your garage or workshop. To control the temperature of the room, I’d recommend installing the Mr. Heater thermostat. This will ensure that the area remains at a comfortable temperature and prevent burning up too much gas, thereby reducing your running cost.

The Mr. Heater Big Maxx range is built to last, with an extremely durable design. They are very confident of their products and offer a 3-year warranty as well as a 10-year warranty on the heat exchange. I really don’t think that you need to worry about hauling out your hard-earned cash on one of these garage heaters. They’re very reasonably priced and offer excellent quality.

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Mr. Heater Big Maxx MHU80NG (F260560) | 80,000 BTU

Uses : Residential Garages, Metal Buildings, Warehouses, Agricultural Building, Storage Buildings
Warranty 3 year Limited on parts and burner, 10 year limited on heat exchanger

Features:

• 80,000 BTU per hour heats up to 2,000 sq. ft.
• Easy outside access to thermostat and A/C terminals and gas connection
• Limited 3 year warranty on parts and burners
• Powered exhaust allows for vertical or horizontal venting
• Natural Gas to Liquid Propane conversion kit included
• For use with natural gas
• Heats up to 2,000 sq. ft.
• Spark ignition features self-diagnostic control module
• Includes 2 angle brackets for ceiling mount
• Low Profile Design – Can be installed in low-ceiling buildings
• Minimum 8 ft clearance from floor to base of heater required
• 1/2″ gas connection
• Category 1 vertical, category 3 horizontal venting

✓ View or download the MANUAL for the Mr. Heater Big Maxx MHU80NG.

The Mr. Heater Big Maxx MHU80NG is very much the same as the smaller MHU50NG. It has the same design features and operation. This includes the horizontal and vertical vents, a fan, mounting brackets and external gas and thermostat connections. It looks exactly the same, only bigger.

If you want to heat a larger area (up to 2000 square feet), the 80,000 BTU Mr. Heater Big Maxx MHU80NG will be the better option. Of course, it will cost slightly more than the smaller model – who would expect otherwise? Measurements are 25” X 18.5” X 17” and it weighs 88.45 lbs.

Other than this, it’s the same and comes with the same excellent warranty.

Tech Specs :

• Heating Area (Sq Ft) : 2,000
• Weight  : 88.45 lbs.
• Model : MHU80
• Length 25.00 / Width 18.50 / Height 17.00
• Thermostat Sold Separately
• Safety Tip-Over Switch : No
• Fuel Type  : Propane
• Heat Type Forced : Air
• High Limit Safety Shut-off (HLS) : Yes

Learn more about Mr. Heater Big Maxx heaters by visiting their site.

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Modine HD60 Hot Dawg | HD60AS0121

60,000 BTU : Power Vented HD Model

Suitable to heat : 3 to 3.5 Car Garage

Features:

• Produces up to 60,000 BTU/hour to keep you warm and comfortable on cold days
• Ideal for residential, commercial and industrial applications
• Accommodates piping from the left or right
• Noise Level : 59 dB
• Surface mounts to the ceiling
• Low-profile design great for tight spaces
• CSA listed
• Trouble-free motor dependability
• Simplified side-wall or roof venting with small-diameter vent pipes
• Hush-puppy quiet operation
• 10 year warranty on heat exchanger
• Lightweight, easy installation 1″ from ceiling
• Operates with natural or propane gas
• Power vented model simplifies side-wall or roof venting with small-diameter vent pipe
• Finger-proof fan guards on all units
• Permanently lubricated motor
• Controls can be either single or two-stage, direct spark ignition, 100% shut-off with continuous retry
• Made in the USA

✓ Documents for the Modine HD60:

• View or download the INSTALLATION/MANUAL
  
• View or download the BROCHURE
• View or download the MAINTENANCE CHECKLIST
• View or download the TECH SPECS

The Modine Hot Dawg range of garage heaters are great units, with a number of models from 35,000 to 75,000 BTUs. Though I have to admit, I have trouble justifying the extra price of this 60,000 BTU model with the two Mr. Heater Big Maxx heaters that we’ve just looked at. Though it does have some redeeming features and there are those that will prefer the Modine HD60ASO121 Hot Dawg over the Mr. Heater Big Maxx options.

This model is a direct vent option, so it doesn’t have a ventilation fan. There is an option for the same model that does include a fan. It has a versatile design for side-wall or roof mounting. It has a small diameter vent pipe that will draw flue exhaust into the heater, maximizing its efficiency. Its design gives it a 1” clearance and it measures only 18” X 26” X 25”. This is a very compact size. So, if space is an issue the Modine is way better than the Mr. Heater Big Maxx equivalents. It weighs 82.7 LBS. Another advantage of the Modine range is that they are incredibly quiet and you probably won’t hear them at all. Of course, the models that use a fan will be a bit noisier.

Video | Modine Hot Dawg Installation

It uses an aluminum heat exchange, which is pretty impressive, both for durability and improved efficiency. Like the Mr. Heater Big Maxx heaters, this one can run on natural gas or propane and will, like the others, require an adaptor kit for propane. It also uses a 115V VAC power source and will draw virtually no current as it only really needs to power the ignition spark.

If you’re an auto or bike enthusiast who likes to display your fine machinery in an elegant environment, the look of your garage is likely to be important. While most people see the garage as a storage area and a place where we work, some will want a look that’s more refined. For these guys, the Modine range has the perfect solution. This range of garage heaters has the option of a kit to modify the look of the heater. So if the standard utilitarian look of a regular garage heater is not your thing, you’ll appreciate this extra option that they offer.

Video | See How the Operation of the Modine Hot Dawg Garage Heater

The Modine HD60ASO121 Hot Dawg is, without a doubt, a high-quality item. And for those who prefer to buy American, it’s built in the USA. It has the same warranty as the Mr. Heater Big Maxx heaters, being 3 years for the unit and 10 years for the heat exchange.

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Choosing the Right Garage Heater

Which is better, an electric heater or one that uses a combustible fuel like natural gas, propane or kerosene? The advantage of a fuel burning heater is that they heat the area very quickly and efficiently and you don’t need to install any extra wiring as they don’t use much electricity. An electric heater that’s powerful enough to heat your garage will often require a 230V circuit and may draw a lot of amps.

The advantage of electric is that it’s safer. A propane heater can be hazardous if you’re using flammable liquids or solvents, like when spray painting. If fumes enter the heating unit, they may ignite as fuel burning heaters use a flame. However, if correctly installed a natural gas or propane heater is very safe under most working conditions.

The next thing that you may want to consider is whether to use a fan forced or radiation heater. A radiation heater provides a more gentle form of heating in that the heat is absorbed by the objects in the room and then radiated out from them. This can be more comfortable than having the hot air blasted by a fan. The downside of radiation heating is that it heats the objects closest to the heater and you’ll probably have to work in quite close proximity to the heater. A radiation heater will heat the whole room over a long period, but the area around the heater will always be hottest. A fan assisted heater will circulate the hot air around the room and will give a more even heat distribution.

Video | How to Install A Garage Heater

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Effectively Heating Your Garage

Whenever you’re looking at controlling the temperature in a room, insulation is vital – this is important whether you’re heating or cooling the area. You want to keep the air at the desired temperature, without the outside weather conditions affecting the temperature inside.

Because a garage is not built for human habitation, little care is taken when considering the comfort inside. To save on costs, many garages don’t have the same level of insulation as you’ll find inside your home. Insulating your ceiling and walls will make the area more comfortable to be in and drastically reduce your heating costs.

Keeping the hot air in and the cold air out may also require sealing up air gaps. Roller doors are not the best for keeping the heat in. While we can’t do away with them, we can make the garage doors more heat-friendly. Most roller doors will have a flexible rubber seal at the bottom to make sure that the door seals against the floor and prevents air from flowing in or out. If your garage doors don’t seal properly, this can be easily remedied.

Flexible foam rubber strips are readily available and are the ideal solution for sealing any door or window. You just need to get a roll of foam rubber that matches the thickness of the garage door and glue it to the bottom of it. Many of these products are self-adhering in that they have the glue already applied and you just need to peel off a protective strip and apply it to the surface. Though, I’ve found this glue to be inferior and using a contact adhesive works much better.

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How many BTUs do you need to heat your garage?

British Thermal Units (BTUs) are the most common units of measurement for heat transfer. It basically indicates what amount of heat is transferred into or out of an area, depending on whether you’re heating or cooling the room. If we’re calculating the heat transfer in BTUs, it’s important to look at the volume of the room and not just the area. So this means that you’re not just looking at the square feet of the floor, but the ceiling height as well. You’re heating the entire volume of the room.

Because conditions vary, you may have an above standard height ceiling and you may also not have the best insulation, we can only give a basic indication of what to look for when determining how many BTUs you need to heat your garage.

Let’s assume that you have a standard ceiling with adequate insulation. When talking insulation, I’d say a minimum of 4” in the walls and 6” in the ceiling is adequate. If you don’t have good insulation or your ceiling above a height of around 8 Ft, you’ll need to adjust your BTUs accordingly. Without insulation, you’ll need about 30% more heating and the ceiling height will need to be adjusted by the percentage difference between the standard height and your actual ceiling height.

Based on these factors, we can say that a standard 2½ car garage will need a heater capable of 40,000 BTUs and a 3 car garage will require 60,000 BTUs. This is using a forced air (fan) heater. Infrared electric heaters will require less heating, although they heat slower. In the case of these heaters, you can work on 30,000 BTUs for a 2½ car garage and 50,000 for a 3 car garage.

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Garage Heater Safety

Installing your garage heater can be quite simple if you know what you’re doing. However, there are some safety concerns, especially if you’re using natural or LP gas and you may want to get a professional in. Installing the heater safely is only the start and you should ensure that you’re working in a safe environment.

The main difference between heating the garage and any other room is that you’re probably storing hazardous materials in the garage. Cans of gas, paint, solvents and aerosol cans all pose a fire risk. This means that you need to take care where and how you store these items. You should avoid storing any flammable items or chemicals close to the heater.

If your garage heater uses a kerosene, natural gas or LP gas burner, you must be cautious about releasing any flammable fumes into the air as they can easily combust when they come into close proximity with the heater.