What is the difference between open and glass-fronted fireplaces?
When considering a gas heater for a house, amongst the more common questions asked is: What’s the difference between open fronted and glass fronted? While visually there may seem little difference, what you don’t see is where the real differences occur.
Open gas fire efficiency
Open gas fires work in much the same way as a traditional solid fuel open fireplaces using a cleaner fuel source. This means the fire will use air from the room as an ignition source, and while a certain amount will be drawn under the fire and recirculated into the room whether fan assisted or through natural convection, a proportion of the rooms warm air will be drawn into the fireplace box and travel out through the flue.
An open fire also provides a vent for warm air to be drawn out of the house when it is not in use much as a traditional open fire does. Both of the above will require replacement air from outside to be introduced to maintain airflow. Therefore as the fire attempts to increase a room’s temperature it requires more air. This, in turn, means that energy input (gas) to heat output (kW) becomes disproportionate thus reducing efficiency.
Glass front gas log fire efficiency
As the gas log fire is sealed from the room there is no requirement for replacement air, or loss of heat through the fire. Air from within the room is pulled in through the front of the fireplace surround and over a heat exchanger then circulated back via either a fan or duct system.
This reduces the temperature difference between the rooms incoming and outgoing air to be minimum, thus achieving a more constant temperature. This type of system allows both the above Escea ranges to run at between 85-90% efficiency.
While efficiency is sometimes confused with output, they are totally different scenarios. Efficiency as described above is the amount of input (gas) used to produce an output (heat). Therefore in the case of the Escea DX1500, DX1000, DL1100 and DL850 fireplaces 85–90% of gas is turned into an output of between 8.4 – 10.4Kw.
For an example of the benefits of a glass fronted over open fronted gas fires, consider the following. An open fronted gas log fire currently on the market puts out 2.3Kw while the same heater fitted with a glass front achieves 6.97Kw, for the same input. Therefore not only using the gas more efficiently, but giving a 300% increase in output.
The requirement of open fronted heaters to draw air in means for the flue to work at maximum efficiency it needs to be vertical and straight (other factors such as diameter and length also need to be considered). Because of this, these types of fires can only be installed in positions where either the flue can be exposed or built into a chimney breast style structure. Both of these installations will require the roof cladding to be penetrated.
Fires such as the DX-Series or DL-Series ranges from Escea are designed using the very latest flue technology. The Powered Direct Vent system in these units uses a fan to both bring air from outside into the fire box and expel exhaust back out. Using this technology the fire is able to be installed in almost any situation with the power flue able to be installed vertically, horizontally or even through the floor.
Read our blog about the difference between unflued and flued gas heaters.
So which gas fireplace to choose?
If your choice of fire is made solely on the visual attributes of the fireplace then it is as simple as the personal preference. However, if you wish to combine something aesthetically pleasing with efficient cost effective heating the choice always has to be the glass-fronted option.