Vented or Vent-Free?

[djradz]

As others have said, they work nice, very little odor, but you will notice condensation, starting on your windows and door and eventually everything. It gets worse when you've operated for a while, and then shut down. The heat leaves, but not the moisture. The only way you won't have too much of a problem is if you have a lot of air leakage. Good luck otherwise.

 

[gsxr1100]

I have a Vermont Casting (B-vent) in my finished basement. It is 34,000 BTU's and works great. Can heat my house if needed (and more). Installed and ran vent (25 feet) myself.

As others have stated moisture (condensation) could be any issue. I would not worry to much about that. My humidy is between 35 to 50% (depends on outside temp) from my humidifier setting. Either %, I get condensation on windows.

I know in MA I roughed in the piping and had a friend do the final look over. Even then, the plumber means nothing since the fire chief has to come in and give the final ya or ba. Gas pipe is not rocket science here.

I would do what is easier or uses less fuel and setup.

 

[djradz]

If you've vented it, the flue gas that is, then condensation would not be an issue. You only get significant amounts when the byproducts, CO and water vapor, aren't piped outdoors. Hopefully that 25 feet has some significant rise to it or is power-vented.

 

[gsxr1100]

I know this winter with 2 weeks below zero nights (112 to -20), I have 10X more water from condensation from my humidifier then my fireplace vent. My vent does get some water in it (since I take it apart to look) since the linear is non insualted and single alu wall. Some water is normal.

Case in point water should not be an issue so to speak. I get more from hot/cold temps. I do know some people that have ventless and then like it. I got b-vent since I had 90% of everything down (removed old dirty wood buring fireplace).

 

[penokee]

Totally against ventless, based on past experience. Used them in my cabin a few years back and was constantly having sinus headaches - changed to vented fuel oil heater and headaches went away. I have to believe that something in the cabin air from the ventless was causing my problem. Would never - ever sleep in a room with ventless, even with window open. IMHO.
penokee /forums/images/graemlins/smile.gif

 

[PineRidge]

I do not believe in any vent free appliances. Read the fine pint and they will always tell you to use additional air like a cracked window. Why, if they are safe?

 

[NY_Yankees_Fan]

I called two plumbers and they came by today to give me an idea how they would charge to install the unit. One plumber told me how great these ventless units are and that he has the same model in his garage. This guy was the owner of the company, good size company has 10 trucks on the road, go figure. /forums/images/graemlins/confused.gif

Anyway one guy want $350 written estimate and the other said less then $100, verbal only. Now I am thinking for $15 in parts I will just it myself. /forums/images/graemlins/grin.gif

 

[PineRidge]

Tom here's some food for thought. One of the byproducts of the combustion process is water vapor, which is normally carried out by the flue-pipe. How do you suppose that a vent-less heater takes care of that same problem?

I used a radiant vent-free heater in an attached garage for one season since the gas company gave it to me for free. After my tools started to rust and I had problems with ice crystals forming on the windows I quickly took it down and sold it at eBay.

Hung a vented Reznor unit heater in it's place, and am glad that I did. The vent-free heater may please you but it's better not to expect too much then you won't be too disappointed if it doesn't.

 

[OkeeDon]

Been reading all of the comments about vent-free, and can't argue with any of them, as far as your local environment is concerned. Here in Florida, however, vent-free is perfectly acceptable in the majority of cases. First of all, regarding the moisture problem, there is little the appliance can do to increase the already high humidity levels we have year-round. Second, our houses are not built anywhere near as air-tight as the ones in many areas of the country. I've read the requirements for some states in the upper MidWest, for example, and the houses are so tight that every source of combustion has to be considered in planning enough replacement air. This includes b-vent appliances, which, while venting the by-products of combustion, do not arrange for air replacement the way a direct-vent appliance does. Some of the combustion sources that can cause problems are b-vent fireplaces and stoves, gas water heaters, gas ranges and ovens, wood-burning fireplaces, etc.

I've had vent-free cast-iron stoves installed in my house, my North Carolina cabin, and my daughter's house for years with no problems. We use them for cold snaps instead of using our electric forced-hot-air systems. We burn them night and day during the cold snaps, which can last up to 5 or 6 days in Florida, with no ill effects. I doubt the added moisture content is as much as cooking a pasta dinner.

If I lived in an area with little humidity, and I was sure my house was air-tight, I might have a different attitude. It's instructive that most of the states which prohibit vent-free appliances are in the North, while most that do permit them are in the South, and the same geography generally applies to how air-tight the building codes require the house to be.

Going all the way back to Rozett's question that started this thread, he says that he wants to put the appliance in a 3-season room in a 200 year old farmhouse. His may be the exception, and that's for him to judge, but most 200 year old farmhouses leak air like a seive, and the same is true for most 3-season rooms. If his is typical, I wouldn't hesitate to install a vent-free appliance.

 

[PineRidge]

Don has a few very good points about construction differences that might compensate for the water vapor from a vent free heater.

I think most problems that occur in our area come from the fact that we have cold winters. The heater may be used to warm a area such as a garage for a day or two so that a homeowner can work on a tractor or other project then when the heater is shut back down the humidity becomes more of a problem in the now unheated area.

I am also concerned with any heater that competes with me for oxygen within the same room where I live. I know most of them have oxygen sensors that will shut the unit off if the O2 level drops to a certain point but I'm just not real comfortable wondering what could happen if that little device might malfunction while that heater is keeping my snoozing family comfortable.

I say it's purely a personal choice, just the same as using a seatbelt and ROPS while using your tractor. The choice is up to you, it boils down to your own personal comfort level.