"Vented" Gas Log Sets...For An Inexpensive Gas Fireplace, "Without
The Heat"
Mar 07 '02
The Bottom Line Vented Decorative Gas Log Sets are not Heaters. They are cost effective alternatives to
heater rated gas fireplace inserts, for those who don't want any heat but, want instant ambiance.
This is an updated look at the Decorative rated vented gas log sets available. The first thing I wanted to stress,
is that these products are not energy efficient. They are approved and classified as Decorative gas appliances.
They are designed for just that, providing a decorative effects flame in your existing vented wood fireplace. Just
don't buy one, expecting them to produce any useable heat. They will invariably use more energy than they
Converting an existng wood burning, masonry or steel fabricated fireplace to a gas-fired unit has never been
easier. Decorative, retrofit Gas Log Sets are considered the poor cousins to the Heater rated gas fireplace
inserts by many people. They are the least expensive retrofit option and there are a number of pro's and con's
to consider before buying one.
Generally, anyone in a warmer climate, who doesn't want more heat added to a given room, but, wants a
running fire in the fireplace for ambiance, without the mess and fuss associated with burning wood. These
products are especially more popular in municipalities that have bans on burning wood during certain times of
the year. More and more cities and towns throughout North America are concerned about smoke pollution,
from wood fires, that tends to settle in low lying areas. So what's the point of having a fireplace, if you can't use
it? In these cases, a number of people have turned to Gas Log Sets or Gas Fireplace Inserts, which meet local
pollution restrictions.
There are also quite a few people who already have, well balanced, central heating systems that heat their
homes adequately. They know that the old wood fireplace drew more heated air out of the house than it added
and now they simply want to convert it to something they can light, at the flick of a switch. Again, the low fuss
factor is the big sales feature.
Anyone who bought one, thanks to an over ambitious sales person, expecting the gas log set to generate more
heat than their wood fireplace did. These are the unfortunate, dissatisfied owners of gas log sets, who didn't
have the benefits of reading this review before they bought one.
Let's face facts, these products are designed to produce the illusion of a wood fire. They can never truly
simulate a wood fire. Real wood fires change all the time, as the logs burn down, flare up, or as more wood is
added. Wood fires are interactive events, requiring attention, poking, and chucking a bit more on top. Gas
fireplaces do their very best to come close to these effects and improvements each year are bringing them
closer. However, they aren't interactive, you shouldn't poke them or stoke them.
There have been "some" gas log sets I've seen recently are very realistic. Some have logs with knot holes and
flames licking out at different spots. Most have ember beds with glowing ceramic fiber coals and control panels,
that hide away all of the gas piping and controls behind a decorative front facia, or control panel.
First consider, realistically, why you want to convert your masonry fireplace to gas and what you expect from it.
Let me save you the time of reading this whole review. If you want supplementary heat for the room it's going
in, move on to look at your options under gas-fireplace inserts which are almost all Heater rated.
As I've said above, Gas Log Sets are the least expensive gas-fired hearth products for converting an existing
wood fireplace to gas. A gas log set is simply that, a burner, a gas control, usually, a cradle to hold it all
together and a set of fake non-combustible logs. All are designed and positioned to simulate, as realistically as
possible, a wood fire. Remember, a simulated realistic wood fire, is always subjective. What may look realistic
to you may look pretty fake to me or vica versa. Realism is in the eye and the imagination of the beholder.
If you've decided that you don't want the fireplace to contribute any amount of heat to your home and you have
no concerns about fuel costs or if you don't plan to use it very often, except for improving the ambiance when
entertaining. The simple gas log set is the kind of product you should consider.
Since the average gas log set has no restrictions with regards to firebox size, they are usually set up to burn
anywhere from 30,000 Btu's to 80,000 Btu's per hour or higher. Most larger gas log sets will burn two to three
times more fuel than a heater rated insert. They will also use large amounts of secondary air from the room in
which they are installed. In most cases they will draw more heated air up the chimney than they can deliver
to the room. If you live in a colder area of the country, this means your central heating system must pick up the
difference and work a little harder to maintain the comfort level you want. On the other hand, if you live in
Florida or parts of California, it probably means you are happy, because the outside temperature is 75 F and
you've got the air conditioning going. The fireplace is just on for effect.
The only exception to this, "no heat rule", from certified Decorative vented gas log sets, is with the so-called
99.9% unvented gas log sets, which I view as; products for people with a death wish and I have already made
my epinion clear on the dangers of unvented gas appliances in many previous reviews. Once again, don't buy
unvented (vent-free, ventless) gas log sets and if you do buy one, don't use it, if you care about your health.
Certainly, don't buy an unvented gas log set if you don't want heat added to the home. (In addition to increased
humidity and indoor air pollution. Sorry, I couldn't resist slipping that in)
The damper from the old wood fireplace must be disabled to remain in the open position or removed
This safety requirement of national installation codes is intended to ensure that no one will ever operate a gas
fired log set with the damper closed. People who do that by accident with a wood fire are quickly engulfed in
smoke from the fireplace. However, a gas log set will simply spill products of combustion into the room and
could injure or even kill people, operated that way. That is the reason for the government mandated
requirement to remove or disable the damper in the open position.
For all you "do-it-your-selfers" out there, who think you can beat the system by leaving the damper in and
turning it down to generate some heat. You are literally playing with fire and gambling with your health, maybe
even your life. These products are not equipped with any safety devices for detecting spillage into the home
and neither are human noses. What sometimes seems like a clever idea may end up killing you or someone
you love.
The first advantage to a gas log set is that they are inexpensive units to buy. The chimney does not have to be
lined, in fact, according to gas codes, it can't be lined with a gas log set, further lowering installation costs. A
simple gas line to the fireplace and you're in business. No more wood to chop, no more ashes to clean out and
remember, no heat from a vented "Decorative gas log set.
As opposed to a roaring wood fire, a gas log set is under the full control of the operator. It is the consumer's
choice to flick it on or off, to turn it down, or to turn it up.
The major drawbacks are that the operating fuel costs will be higher, there could be intermittent cold draft
problems coming from the fireplace, and there will usually be a continuous draw of heated air out of the
home, whether the gas log set is operating or not, after the damper is permanently opened. These products
are considered to be negative energy users in your home, designed specifically for effects, aesthetics and
While it is an open flame, they are not designed to handle the drippings from cooking marshmallows and
hotdogs. Nor are they a good place to toss old newspapers and garbage. These kinds of creative, and fun
activities will eventually clog up burner ports and create hazardous conditions, from delayed ignition to carbon
monoxide poisoning. Trust me, I had to put that warning in, because folks have done it.
Although as I've stated above, the flame is controlled, the open flame may also be considered as a drawback if
you have young children in the home. Children should always be supervised around any type of open flame.
That would hold especially true for a wood fire as well.
It is important to remember, if you choose to go with one of these products, don't necessarily choose the lowest
Btu/H input. Studies have shown that if the fireplace temperatures are not kept high you can expect problems
within your chimney, since it is not lined with a protective aluminum liner with a gas log set. With so much
excess, dilution air from the room, mixing with the flue gases, the temperatures within the chimney can be
relatively cool and may condense. 30,000 Btu's is considered the minimum input rate that one of these
products should be fired at in order to generated sufficient draft and maintain a hot, dry chimney.
Personally, I recommend 40,000 to 50,000 Btu per hour for an average masonry chimney that is 25 to 35 feet
high. (The average chimney height of a two or three storey home.) You will burn a little bit more gas per hour of
operation, but, remember, these products are probably only going to be used a few hours per evening. A unit in
this Btu range will generally burn hot enough to keep the chimney dry and venting all products of combustion.
The hotter the chimney, the better the draft.
Cool damp chimnies will promote condensation and that moisture is acidic and will attack clay tile liners and
mortar joints inside the chimney. In short, it is more cost effective to burn a little more gas and keep the
chimney dry, than to have to rebuild the chimney every five years. If you have an outside steel chimney or a
very tall chimney, you really should go with a higher Btu/H rating. I have a problem with the units that go higher
than 60,000 Btu's. Bigger isn't always better, in this case.
Most of these products come with push button ignition and adjustable gas valves for turning the flame height up
and down. However, it is not advisable to run them on the low fire setting for very long if you want your chimney
to remain intact and good draft action to take the fumes away.
A gas log set can not be connected to a room thermostat and work. Since the room temperature will not be
affected by any great amount whether it's on or off. Most people simply connect them to an on/off toggle type
wall switch. However, a remote control can be connected to them for those of you who don't like to get off the
couch. Just try not to mix it up with the controllers for the TV, stereo, DVD, VCR, and your robot dog that brings
you beer.
Take time to check what material the simulated logs are constructed from. Older models mostly used concrete
or a mixture very similar to concrete. The logs tended to be extremely heavy and not very attractive to look at.
Something like elephant droppings. More recent products are using ceramic fiber logs. These do tend to give
more glowing effects when the flames lick them. Whereas the heavy concrete type don't glow at all. My only
concern, surrounding the ceramic fiber logs, is that there has not been enough studies done to ensure that
these products are safe if they wear down or break. Ceramic fibers have been suspected of acting much the
same as asbestos fibers once airborne. Ceramic fiber logs are also much more expensive than the older
concrete type.
The good news is there are log sets on the market, constructed out of a lightweight yet hardened material, that
is neither concrete or ceramic fiber. These logs do glow when the flames impinge and they are not substantially
more expensive than concrete logs.
If I have turned you off to the idea of a gas log set by any of the drawbacks mentioned above. Consider a low
Btu input gas fireplace insert. When gas inserts are installed, the installer is required to also install an aluminum
liner in the chimney (to protect the chimney from corrosion). Some come ready to fire at, as low as, 20,000
Btu's per hour, and with a gas turn down control that can be adjusted down to 10,000. Pick one with a low
efficiency rating if you don't want supplementary heat. Ask if the circulation fan is optional and don't get one if
you only want the decorative aspects of the product. (Personally, I would get it, as it is less expensive to buy
with the original unit than to add at a later date.)
Some of the new low Btu inserts produce a great effects flame with very little energy waste and can be
adjusted to provide very little heat. If the furnace ever quits working, you may find this product is a useful back
up for emergencies, since most of them don't require any electrical supply in order to operate. More on GasFired Inserts in another review.
Gas Log Sets have a place in the market. People in the southern states, where climate conditions don't call for
heat, seem to enjoy the benefits of them. California has a large market for gas log sets. Alternatively, I have
known people in the cold white north of Canada, whose heating systems were generating all the heat they
needed, and they simply wanted an aesthetically pleasing flame in the fireplace. You can also usually find them
in restaurants, pubs and other public places, where, their only job is to set the mood as you wine and dine.
Use a competent and qualified gasfitter. They should come out and have a look at the job before installing the
gas log set, to look at the best way to run the gas line and the type of damper system they will be disabling.
Make certain the damper has been blocked in the open position or removed by the installing contractor.
Whenever someone has decided to convert an old used wood fireplace they should always have the existing
chimney cleaned, (one last time!) by a registered chimney sweep. The last thing you want is a lot of very
flammable creosote inside the chimney with a roaring gas fire down below. Chimney fires have been known to
burn down houses very quickly in extreme cases.
Before anyone installs either a gas log set or a gas fireplace insert, the inside of the fireplace should be
thoroughly cleaned of soot and ashes. The cleaning should include any clean out ports for the ashes.
Installation of a gas log set is usually a pretty quick and easy job. Most installers can be in and out within a
couple of hours, including time to check their own work for gas leaks and cleaning up. If they're competent,
they've left no mess behind.
Whether you go for a gas log set or a gas fireplace insert, the greatest advantage is a clean burning fire, at the
flick of a switch, with no wood to chop and haul and no ashes to clean up later.
Vented gas log sets are very simple systems, for people with a desire for a simple effects flame.
They are equipped with very few controls, other than a gas valve and a pilot. So, if that's what you've decided
upon, you can expect it to run heat and trouble free for many years to come. 
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