Converting vented logs to non vented

agallant80

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I have a fire place in my house that needed some work so the privous owner decided to put in a vented gas insert to save on the chmini rebuild. The issue with this is all of the heat goes up the chmini instead of the house. I would like to convert the gas insert to a direct vent. I know this requires new logs, I can take the glass off of the existing insert and plug the vent hole with some sheet metal. Any thoughts on converting?
 

Vintin

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Re: Converting vented logs to non vented

Could be deadly.
 

bigdee

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Re: Converting vented logs to non vented

I have a fire place in my house that needed some work so the privous owner decided to put in a vented gas insert to save on the chmini rebuild. The issue with this is all of the heat goes up the chmini instead of the house. I would like to convert the gas insert to a direct vent. I know this requires new logs, I can take the glass off of the existing insert and plug the vent hole with some sheet metal. Any thoughts on converting?

I do not know exactly what you have so I can not make any recommendations for you. I have converted my logs to unvented,however they are about 40 years old with heavy ceramic logs. I simply shut and sealed the damper and adjusted the burner for a blue flame. A blue flame is unrealistic looking but that is what I had to do to make it safe and not set off the carbon monoxide detector. A word of warning if you use an unvented gas heater the combustion by-product is water...and lots of it. Water condensation on windows most likely will be a problem if you use this as a primary heat source.
 
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dingbat

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Re: Converting vented logs to non vented

The issue with this is all of the heat goes up the chmini instead of the house. I would like to convert the gas insert to a direct vent. I know this requires new logs, I can take the glass off of the existing insert and plug the vent hole with some sheet metal. Any thoughts on converting?

It sounds like you want a vent-less system, not a direct vent. You still need a vent with a direct system. A direct vent system uses a double walled pipe. air is drawn into the system on the outside and the combustion by products are exhausted in the inner pipe.
 

Tnstratofam

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Re: Converting vented logs to non vented

Our company has done several vented log to vent free log conversions over the years. Vented logs provide that natural wood fire look while loosing most of the heat up the flu. Vent free logs don't look as good however all your heat is radiated out into the house. Great for a backup heat source when the power fails. If you purchase vent free you can seal up the flu with sheet metal. Make sure your chimney cap is still good and you should pay to have it checked out for structural problems that could lead to water damage.

Some safety tips:

1. ALWAYS have a carbon monoxide detector in your home if you have any appliances that us natural gas, propane, fuel oil, kerosene, or even if you burn wood. REPLACE the batteries annually. REPLACE the detector every 10 years.

2. DO NOT use a glass enclosure over vent free logs unless you purchase a fireplace insert that has one. If your fireplace has glass doors and you put in a set of vent free logs make sure you open them when you use them.

3. Everybody wants to save a dollar. Me included, but I would recommend you talk to a local heating and air conditioning contractor for your specific needs. The people in the hardware stores, I. E. Lowes, Home Depot, Menards, Ace Hardware are sales people not installers and or technicians.:faint2: They may be well trained, but our company for example has liability insurance to cover us if we screw something up and mess up your house. Or burn it down!:eek:


Just .02 cents from a Nate certified Technician here though.:D
 

Fishing Dude too

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Re: Converting vented logs to non vented

I will say be careful or you will win a Darin Award.
 

CharlieB

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Re: Converting vented logs to non vented

I believe Darin is Darwin's younger brother that took over the family business when Darwin started slacking off.
 

agallant80

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Oct 25, 2010
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Re: Converting vented logs to non vented

Our company has done several vented log to vent free log conversions over the years. Vented logs provide that natural wood fire look while loosing most of the heat up the flu. Vent free logs don't look as good however all your heat is radiated out into the house. Great for a backup heat source when the power fails. If you purchase vent free you can seal up the flu with sheet metal. Make sure your chimney cap is still good and you should pay to have it checked out for structural problems that could lead to water damage.

Some safety tips:

1. ALWAYS have a carbon monoxide detector in your home if you have any appliances that us natural gas, propane, fuel oil, kerosene, or even if you burn wood. REPLACE the batteries annually. REPLACE the detector every 10 years.

2. DO NOT use a glass enclosure over vent free logs unless you purchase a fireplace insert that has one. If your fireplace has glass doors and you put in a set of vent free logs make sure you open them when you use them.

3. Everybody wants to save a dollar. Me included, but I would recommend you talk to a local heating and air conditioning contractor for your specific needs. The people in the hardware stores, I. E. Lowes, Home Depot, Menards, Ace Hardware are sales people not installers and or technicians.:faint2: They may be well trained, but our company for example has liability insurance to cover us if we screw something up and mess up your house. Or burn it down!:eek:


Just .02 cents from a Nate certified Technician here though.:D

From what I understand the direct vent logs still need to vent up the chmini, you just put this stopper thing that leaves the flue a little bit open. I also understand that you need diffrent logs seeing as the logs I have have a pilot light and a light switch to turn them on. My current box you are able to remove the glass and there is a bracket over the vent at the top that you can slide a plate in to to close it off a bit. Does this sound right?

Remove the glass
Change out the logs
Install plate in to bracket to close off vent 80% of the way or so (there is a stop so you can't close it off all of the way)
 

bigdee

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Re: Converting vented logs to non vented

From what I understand the direct vent logs still need to vent up the chmini, you just put this stopper thing that leaves the flue a little bit open. I also understand that you need diffrent logs seeing as the logs I have have a pilot light and a light switch to turn them on. My current box you are able to remove the glass and there is a bracket over the vent at the top that you can slide a plate in to to close it off a bit. Does this sound right?

Remove the glass
Change out the logs
Install plate in to bracket to close off vent 80% of the way or so (there is a stop so you can't close it off all of the way)

Your talking about VENTED FLUE, meaning 20% of heat goes out chimney. Unvented flue, 0% goes out chimney.
Direct vented means combustion intake air comes from within room. Indirect vented means air is drawn in from outside.

Four different things.
 

Tim Frank

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Re: Converting vented logs to non vented

A man jumps out of an airplane with a parachute on his back. As he's falling, he realizes his chute is broken. He doesn't know anything about parachutes, but as the earth rapidly approaches, he realizes his options are limited; he takes off the parachute and tries to fix it himself on the way down. The wind is ripping past his face, he's dropping like a rock, and at 5000 feet, another man goes shooting up past him.
In desperation, the man with the chute looks up and yells, "Hey do you know anything about parachutes?!"

The guy flying up looks down and yells, "No, do you know anything about gas fireplaces?!":D

Buy a DV unit.
We've had one for 10+ years.
They are great. :)
 
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bigdee

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Jul 27, 2006
Messages
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Re: Converting vented logs to non vented

A man jumps out of an airplane with a parachute on his back. As he's falling, he realizes his chute is broken. He doesn't know anything about parachutes, but as the earth rapidly approaches, he realizes his options are limited; he takes off the parachute and tries to fix it himself on the way down. The wind is ripping past his face, he's dropping like a rock, and at 5000 feet, another man goes shooting up past him.
In desperation, the man with the chute looks up and yells, "Hey do you know anything about parachutes?!"

The guy flying up looks down and yells, "No, do you know anything about gas fireplaces?!":D

Buy a DV unit.
We've had one for 10+ years.
They are great. :)

Love it. If the OP is just seeking info thats fine but if he is trying to DIY that is another matter. I converted mine but I am also trained and highly experienced in industrial and residential HVAC gas burners.
 

Tnstratofam

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Aug 18, 2013
Messages
2,679
Re: Converting vented logs to non vented

OP should contact a professional. AS I recommended in my previous post. You know what they say opinions are like elbows, Everybody has a right one and a wrong one.:D
 

Volphin

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Re: Converting vented logs to non vented

I was always told that they cannot be converted without changing burner systems.
 

bigdee

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Re: Converting vented logs to non vented

I was always told that they cannot be converted without changing burner systems.

If the burner intake air shutter can be opened enough to get a blue flame without any orange it can be unvented. Be advised that some jurisdictions/states do not allow unvented heaters. A unvented does not produce carbon monoxide but it can deplete the oxygen in the room if the house is tight and does not have a source for outside air to be drawn in. I have heated my home for +40 years with one 40,000 btu heater, one 40,000 btu gas logs and a 30,000 btu garage heater...all unvented.
The only problem I have is the humidity stays high but that is OK because dry air just about kills me! I need to occasionally run a de-humidifier to keep the windows from condensating on the inside.
 
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