What is an open flue gas heater

Gas heater technical information

If your gas heater is not working and the evenings start to turn a bit cooler, and the mornings aren’t as dazzling as they were before, you’ll probably want to put on your boots and look for a new gas heater to keep you warm. When choosing the best gas heater for your house, you should ensure that you have all of the facts as far as gas heaters go. So, what exactly do phrases like ‘flued’ and ‘unflued’ imply when it comes to gas heaters?

A flued gas heater uses a flue pipe or chimney to remove combustion products from your house. This implies that gas-fired flued heaters within your residence do not emit combustion gas as well as water vapour into your spaces. They come in natural gas as well as LPG flued gas versions. Direct vent and balanced flue kinds of flued gas heaters are also available, which draw burning air from outside your home, resulting in fewer draughts.

The amount of air sucked in is equivalent to the volume of exhaust gas emitted by the flue. A flue in a gas-fixed flued heater transports the combustion gases outside of your property. On the other hand, Flued heaters are less fuel-efficient than non-flued gas heaters. Flued gas fireplaces with an open front are likewise less efficient than those with a closed front. If you choose a glass-fronted gas heater, you will save money on your utility bills and help preserve the environment.

These fireplaces, on the other hand, are often more costly. This is where you should assess the benefits and drawbacks of spending lots of money on a heating element that is more energy-efficient and healthier for your house. Read on if you are keen on finding out what an open flue gas heater is and how it operates.

What is an open-flued heater?

Open-flued heaters use indoor air to fuel the fire and exhaust combustion products through a flue. In some cases, insufficient ventilation and the usage of exhaust fans can suck carbon monoxide back into the room. The burning circuit is subjected to air pressure from both inside and outside the room at the burner input and also at the flue terminal outside due to its design.

As a result, factors like wind or the operation of equipment like washroom exhaust fans can reduce the air pressure within the room, resulting in an adverse pressure condition. Airflow through the flue may become limited or even reversed if the negative pressure is severe enough. If the burner’s source of fresh air is cut off, the flame will release a lot of carbon monoxide.

Numerous natural draught open-flued heaters have a draught deflector to keep the burner from being affected by variations in the flue. In the occurrence that the flue is obstructed or that there is negative indoor pressure, the draught valve is an opening in the flue that enables products of combustion to flow into the living space. The hot products of combustion moving up the flue will suck burning products directly past the draught deflector opening to outdoors if the vent is working correctly. On the other hand, the draught diverter is designed to automatically divert fumes towards the living area when there is a malfunction, without blocking airflow to the burner or releasing excessive carbon monoxide.

As a result, the space in which the heater is located needs ventilation to give replacement air and avoid negative pressures from exhaust fans from interfering with the heater’s regular performance. During installation and servicing, gasfitters must test heaters to verify that they do not spew combustion by-products and that any exhaust fans do not interfere with the heater. You must consult the manufacturer or a competent gasfitter to determine if your gas heater is open-flued.

Crucial things to note about open-flued heaters:

• Make use of a thermostat and a timer
• Warm-up big areas
• Instantaneous heat
• They run on LPG or mains natural gas
• Fossil fuels produce greenhouse gas emissions
• Fixed charges for the main gas supply
• LPG bottles have higher operating expenses
• During a power outage they fail to work

Advantages of flued gas heaters

The flue is the principal advantage of a flued gas heater. It sends potentially hazardous carbon monoxide up the chimney and into the atmosphere, where it dissipates quickly. Carbon monoxide (CO) accumulating within your space is the last thing you want as it is hazardous. You can die if you inhale too much CO. Each year, there are reports of individuals becoming gravely ill after taking an outside patio heater or a BBQ indoors.

Therefore, a flue is an essential safety component. When compared to reverse cycle heating, another advantage of flued gas heaters is that they are a more cost-effective means of heating a space. This is especially true with flued gas heaters that use convection. However, the majority of people choose radiant flued gas heaters because they produce a comforting heat that closely matches that of an old-fashioned wood fire.

Their heat production is outstanding, and they are unquestionably an aesthetically pleasing method to heat your house. There’s nothing that is quite like the comfort of home and hearth. Because only a tiny quantity of combustion gases, carbon monoxide, and nitrogen dioxide lingers in the space, flued gas heaters are healthier to use than unflued versions. More extensive options are available, so the size of your living area should not be a factor in your choice.

In addition, mould and mildew growth are less likely in the area of flued gas heaters because less water vapour remains in your space.

Disadvantages of flued gas heaters

On the other hand, flued gas heaters are not quite as energy-efficient as unflued gas heaters since a tiny amount of heat does escape through the flue at times. Remember, professional installation by a licensed gas fitter is required for these units.

Unflued gas heaters

Unflued gas heaters are a much more cost-effective and adaptable choice for your house. It is worth noting that these heaters require constant ventilation in their working area because they lack a chimney. As such, they have no other route for their harmful gases to exit your home. Another sort of unflued gas heater is an outdoor patio and an alfresco heater, which you should not use indoors. You may also obtain unflued gas heaters that are fixed or built-in.

A vast, freestanding unflued gas appliance can be hooked into a gas outlet (gas cylinders or natural gas) or used with an LPG gas tank. Unflued ethanol fireplaces are also available. Since it’s an unflued gas burner, it utilises the air in the room for burning and then vents the exhaust gas into the space via the very front of the heater.

Advantages of unflued gas heaters

• They are readily mobile; you may heat any space with an accessible gas bayonet.
• There are no hot air leaks since all of the heat produced is used to warm the space.
• Unflued heaters are less costly than flued heaters.
• Some unflued gas heaters have safety alert sensors to warn you of the dangers of gas concentrated harmful afterburning fumes, thus guaranteeing the heater’s safety.

Disadvantages of unflued gas heaters

Air pollution is a severe worry when it comes to utilising unflued gas heaters. They can emit nitrogen dioxide and carbon monoxide as a result of burning, both of which are harmful to your health. Indirect impacts such as water vapour, which promotes the formation of mould and dust mites, are another risk connected with gas burners.

Due to the lack of a flue to vent the combustion by-products away, unflued gas heaters have an open front, exposing the flame. This is not an excellent heating choice for tiny children or animals. Modern residences are airtight, with high insulation and limited outside airflow.

This is to ensure that the home keeps heat. In addition, it also ensures that moisture is kept to a minimum. Nevertheless, if you utilise an unflued, open-fronted, and even a natural vent gas heater, oxygen levels may diminish with time, potentially causing combustion problems.

Comparing costs of flued vs. flueless gas heaters

Residential flued gas heaters are more costly to acquire than portable gas heaters. When contrasting comparable sized flued gas heaters (flued LPG gas heaters to portable/flueless gas heaters), fixed flued gas heaters are around 44 per cent to approximately 57 per cent more expensive. If you are installing a gas-fixed flued heater, you may additionally need to acquire an auxiliary flue kit based on the brand and installation scenario.

What size gas heater do you need?

If you choose a heater that is too tiny, it would not be able to sufficiently heat the space. Choosing a heater that is too large can cost you more money, and it may also be dangerous. When deciding on the size of your gas heater, there are several factors to consider:

• The volume of the space to be heated, taking ceiling height into account.
• The climatic zone in which you reside.
• Ceilings and walls insulation, window covers, as well as carpeting.

Is a flue required for all gas heaters?

A flue is required for all interior gas heaters. The chimney-like device is used to vent out contaminants created by gas combustion from a dwelling. You might be inhaling dangerous carbon monoxide if you do not have a flue in your house. Although outdoor gas heaters need not require a vent, the vapours can be hazardous.

Choose the ideal gas heater for your home

A gas heater is a great addition to any Australian house, and they are trendy in the winter. Given the amount of use the heater will receive in your home, you must select the correct model for your needs. As you have seen, an unflued gas heater emits harmful air pollutants and water vapour straight into your residence, whereas a flued gas heater vents them outside the house via a flue or chimney.

This implies that an unflued gas heater can pollute the air in your home, posing a health risk. You have a lot of choices if you are looking for a gas heater. If you are not well-versed in the subject, you will have a hard time distinguishing between the numerous heaters in the marketplace and deciding the best option for the family’s winter comfort. Thankfully, most gas fitters will be able to answer all your questions.

The most prevalent varieties you will encounter on your search are flued and unflued gas heaters. Before purchasing a gas heater for your home or workplace, it is strongly advised that you consult with an approved gas fitter in your area. They have expertise in selecting the optimum system for almost any room and can provide guidance and suggestions for a gas heater that is appropriate for your needs.