Fireplace venting

[Tom Phillips]

I have a client who has a direct vent fireplace in her basement (Nat gas) that vents out at 18" above grade on the side of her house. The vent is the type that is protected, yet still gets quite hot. (hot enough to burn skin) Her concern is that kids will come by and get hurt. Is this a proper installation? I see a lot of them like this and thought they were ok, but told her I would ask the codeman to be sure.
Thanks
Tom

[Jerry Peck - Codeman]

Hi Tom,

Attached is a typical installation instruction exhaust clearance diagram for a Heatilator Direct Vent gas fireplace. There may be slight differences in clearances from model to model, however, this gives an idea of what the clearances typically are.

The attached is from the Heatilator installation instructions from here (Note: place cursor over link, right click, select 'Open in New Window' - http://www.heatilator.com/downloads/ins ... 47_132.pdf ), page 21, and shows that there is no clearance with regard to "people contact" when on the same property, only when over public property or when more than one family may be using the sidewalk or paved driveway.

Basically, the owners are allowed to put themselves, their family members, and their guests at risk, however, they must protect others by having the exhaust at a height of 7 feet above the walking surface.

Being as you stated the fireplace was in the basement, I am curious as to any snow cover and snow depth in your area and the height of that exhaust at 18 inches above grade. With the fireplace on, the snow would melt and not be a problem on the exhaust itself, however, in a large drift of snow I question how far out the melting snow will be and how large of a ventilation area the heat will create. The other hazard would be the gas fireplace being not on, snow accumulation around and over the exhaust, then the gas fireplace is started ... with the direct vent exhaust/intake now snow covered and clogged, and the inherent safety aspect of that with no combustion air and no venting.

I am going to contact someone with much more knowledge in fireplaces and have him respond also as he will cover areas I have not even thought of.

[Tom Phillips]

Thanks Jerry, I will look forward to any insight on this subject!

[Hearthman]

Tom, you must first get the mfrs. listed instructions and find the corresponding page that looks like the one Jerry posted. They are required to have this info. per the listing. The clearances, however, do vary from mfr. to mfr., and even model to model, so you cannot apply them generically.

Yes, vent terminations do get hot. I've measured over 600*F at some terminations. If people can be expected to bump into the termination and it is not feasible to relocate it up out of the way, there are still some things you can do.

First, see if the mfr. makes a heat shield of some kind. For instance, Hearth&Home Technologies, who makes Heatilator, Heat&Glo, & Quadrafire make two shields that have been tested and listed for use with their venting system. For terminations near grade, you may be able to use a "snorkel" cap to get it up a foot or so but that's about it. If snow is a problem/ possibility, it really should be located higher anyway as Jerry pointed out.

The other strategy is simply to install a barrier such as slow growing shrubbery or a well ventilated fence. Be very careful not to encapsulate the termination as it must breathe. You would do well to get your local hearth pro to guide you on options as I cannot see this installation. Also, local conditions such as a dominant wind may affect choices.

The termination cannot be modified outside the mfrs. listing. It must have plenty of air circulation to breathe. It must be protected from damage but be readily accessible for inspection. You take care of it and it will take care of you.

HTH,
Hearthman