Gas Heater vs Portable Gas Heater
When it’s time to buy a new gas heater do you buy a portable gas heater or a one of the flued gas heaters?
Gas heater type, sizing, fuel type, and paying too much are some common mistakes that many people make when choosing a gas heater.
You can sidestep these slip-ups by being informed.
Gas Heating – Find the Best Gas Heater
Avoid these four typical mistakes and you should end up with a brilliant gas heater that impeccably suits your home:
1. Choosing the wrong fuel
2. Selecting the wrong type of gas heater
3. Getting the wrong size gas heater
4. Paying too much
1. Choosing a Gas Heater for the Wrong Fuel Type
You can choose from two types of gas heaters: natural gas heating and LPG gas heaters.
Gas heaters are manufactured with only one gas type and will not work safely with other gaseous fuels.
You need to make sure you buy a gas heater model for the type of gas in your home.
Always double-check that the gas heater for sale is the right fuel type.
But why?
There are two main differences in how LPG (Propane) gas heaters and natural gas (Methane) heating work.
- LPG has a higher calorific value or energy content, so less gas is required to produce the same amount of heat as you would with natural gas.
- The oxygen-to-fuel ratio required for proper combustion. LPG gas heaters require an oxygen-to-gas ratio of approximately 25 to 1, while natural gas heating requires a ratio of around 10 to 1.
To achieve this difference, LPG is typically provided in a smaller quantity but at a higher pressure, drawing more oxygen into the burner.
Never attempt to connect a gas appliance to the wrong type of gas, as it can be extremely hazardous.
If you have a natural gas heater but your home gas runs on LPG, or vica versa, then you will need to either have a licensed professional convert your gas heater to run on a different fuel, or you need to buy a new gas heater that is compatible with your home gas supply.
Modifying gas heaters is always a job for a professional, and conversion is not always possible based on the age and model of gas heater you have.
2. Selecting the Wrong Type of Gas Heater
Gas heaters are broadly grouped as either Portable (unflued) gas heaters or Flued heaters.
Within these groups are sub-groups of radiant, convectors, radiant-convectors, power flued, flued radiant and wall heaters.
Radiant gas heaters warm you much like the sun.
Radiant heaters allow specific spaces within an indoor area to be heated, primarily warming only the people and objects positioned in front of the unit.
They also come in smaller sizes for minor heating applications.
Radiant heaters are generally not suitable if you want even heating within a larger space.
Think of them more as spot heaters.
Convector (Convection) heaters warm your space using convection or air movement.
Along with the gas burner, they incorporate a fan to help distribute the heat more evenly throughout the space.
Convectors are also sometimes referred to as Space Heaters.
Fan driven convection heaters are much more suitable for larger spaces, doing a much better job of even heat distribution than radiant heaters.
However, if you only wish to heat a small area within a larger space, these may be more than you really need.
You should also consider if you want a flued or an unflued heater.
For the majority of people, unflued heaters are quite safe when you follow all of the manufacturer’s safety instructions, including providing adequate ventilation.
Care should be taken when using an unflued gas heater if the family includes very young, unborn, elderly or individuals with some medical conditions, as they may be more sensitive to the emissions.
3. Getting the Wrong Size Gas Heater
Once you pick your type of heater, you will also need to decide what size unit you need, as each type comes in various heat output models.
If you buy a gas heater that’s too small for your home area, it will not be able to adequately heat the intended area. Buying a gas heater that is too large, on the other hand, will cost you extra money, and oversizing can be unsafe.
You can use the table below as a rough guide, or speak to your LPG gas heater’s store representative to determine which size is best for your home or specific use.
Room size | kW output | Gas consumption |
Small (29–42sqm) | 2.9–4.2kW | 13–15MJ/h |
Medium (46–66sqm) | 3.4–6.6kW | 18–21MJ/h |
Large (52–82sqm) | 5.2–8.2kW | 23+MJ/h |
4. Paying Too Much for Your Gas Heater
Many people buy their gas heater unit through the closest retailer, without comparison shopping.
While this may end up being a good deal, it may not be the most cost effective way to buy.
The good news is that you can now compare gas heater prices online for all the major brands including Rinnai, Braemar, Paloma and Cannon.
_______________________________________
More on Correct Gas Heater Sizing
Finding the right LPG/LNG gas heater size for your needs will help keep your room warm without breaking the bank or hurting your energy bill.
What to Consider with Gas Heating
- A number of things need to be considered when determining your heater sizing:
- The volume of the area to be heated, including the ceiling height.
- The climate zone that you live in. Whether you’re in the warmer Australian regions or those experiencing frigid snaps during the cold winter months.
- The physical features of your home, include wall & ceiling insulation, window coverings, and carpeting.
- The kW output of the gas heater. Not to be confused with the gas MJ input.
Heating Area Volume & Climate Zone
The required kW output primarily depends upon the area to be heated and the climate zone in which you live. You want the best LPG gas heater with the right heating capacity (kW) that meets this heat output. The following rough guide assumes your ceilings are no higher than 2.4M:
- Very Cold Zone: 1kW output required for each 8.5m²
- Cold Zone: 1 kW output required for each 10m²
- Cool Zone: 1kW output required for each 13 m²
- Mild Zone: 1kW output required for each 16m²
Gas Heating Adjustment Factors
The indicated heating areas would be adjusted down by 5% for each of the following conditions: houses built on pillars (non-slab), no carpets on floors, no drapes on windows, or a ceiling height exceeding 2.4m.
This must also be factored in when selecting the best LPG gas heater for sale that meets this adjusted heat output.
Deduct an additional 10% if the area does not have ceiling insulation. Please note that this is only a guide, and individual home designs and situations may vary.
Gas Heater Sizing for sale Example #1:
You live in the Cold Zone and want to heat an area 5m X 10m, which equals 50m². Because 1kW will heat 10m², you should need a heater with a 5kW output.
Gas Heater Sizing for sale Example #2:
Same as the previous example, but in this case, your ceilings are over 2.4m, and you have wood flooring instead of carpeting.
You would need to deduct 5% for each of these two items. So, instead of 1 kW heating 10m², it would heat 9m² (10% total reduction).
This means you would need a heater with 5.6 kW of output (50 ÷ 9).
Use kW, not MJ, for Natural Gas or LPG Gas Heater
Megajoules per Hour (MJ/hr) ratings on appliances indicate the appliance’s gas consumption, not the heat output.
Many LPG gas heaters for sale are advertised using MJ ratings.
You need to ask our LPG technicians about the kW heat output rating, which is often incorrectly expressed as just MJ.
Kilowatt-hour (kWh or just kW) measures gas heater output.
Energy Efficiency Matters: Star Ratings for Natural & LPG Gas Heater
Remember to use kW as a comparison and not MJ.
The efficiency of the gas heater for sale, in converting gas energy to heat, is a key factor.
For example, a 25MJ LPG gas heater for sale with a 5.8 Star rating has an output of 6.2kW.
A 25MJ heater with a 2.8 Star rating only has an output of 5.0kW.
As a result, in a Cold Zone climate, they would heat 62m² and 50m², respectively.
This means that the 5.8 Star heater will heat an area 24% larger while using the same amount of gas.
Please refer to the manufacturers’ specifications to determine the exact kW output for each heater you are considering.
Minimum Room Sizing
Portable gas heaters for sale should not be used in bedrooms, bathrooms, or hallways.
Some States specify the minimum room size (volume of room in M³) and minimum ventilation requirements for unflued heaters.
Minimum room size also varies between thermostatically controlled and manually controlled heaters.
All installations must comply with Australian Standard AS5601 – Gas Installations.
Your gas fitter can guide you on many of these points.
Manufacturer Sizing Charts for Natural Gas or LPG Gas Heaters
To make it even easier, most manufacturers, like Rinnai gas heaters, have sizing charts for their heaters based on climate zone maps.
Measure the area you wish to heat and use these charts and maps to buy the correctly sized LPG gas heater for sale.
It is always wise to follow the manufacturers’ advice.
New Residential LPG customer?
New Business LPG customer?
Existing ELGAS customer?
- Elgas to the Rescue with Helicopter LPG Delivery - November 14, 2024
- Outdoor Heaters: Outdoor Gas Heaters – Gas Patio Heater Guide - September 22, 2024
- LPG Meaning – LPG Means: What Does LPG Stand For - August 31, 2024
Steve Reynolds
Technical Consultant
Steve Reynolds is a leading expert in the LPG industry with over 22 years of experience. As part of the national management team at ELGAS, Steve ensures the safe and efficient storage, handling, and transportation of LPG. He serves as the lead investigator for incidents and collaborates with authorities on industry developments.
Steve is a technical advisor to Standards Australia and Gas Energy Australia (GEA), and an active member of the World LPG Association (WLPGA), contributing to global standards and technical reviews. He holds a BSc. (Hons) in Industrial Chemistry from UNSW and has held senior safety and technical roles at ELGAS, making him a trusted authority in LPG safety and standards.