Gas fireplace direct vent location - InspectionNews

Jon mackay · #1 (**permalink**) 06-26-2007, 06:01 AM

This house had a garage added on recently and they left the vent exiting the side of the house which now is a breezway between the house and garage.

Does anyone know if this is ok, it didn't seem right.

Thank you..

David Banks · #2 (**permalink**) 06-26-2007, 07:17 AM

Jon the best thing to do is always try to find the Data plate on the appliance. This will give you the manufacturer, serial number etc. You can then get on line and find Installation manual with proper clearances etc.
Sometimes all the info will be right on the data plate.
Direct vent appliances generally have less clearance requirements than mechanical vents. Under 10,000 BTU's must be at least 6 inch's from any opening into building. 10-50,000 9 inches and over 50,000 12 inch's from any opening into building. Bottom of vent shall be at least 12 inches above grade.
Where there any openings in the breezeway?

Bob Harper · #3 (**permalink**) 06-26-2007, 07:57 AM

Off the top of my head, this is probably allowed. You can terminate exposed on a patio or deck where people walk and could touch it. Most mfrs. make heat shields or cages, which do help. As long as that breezeway maintains a breeze, you're probably ok. For instance, most mfrs. allow you to vent onto a porch as long as its not screened in.

David has given you the best advice--locate the mfrs. listed instructions and go by the chart therein. If you record the model and serial number, you can contact the mfr's technical services for assistance. They can either send you a manual or tell you over the phone. If you go with the verbal response, but sure to note the tech rep's name, date, and time you spoke.

HTH

Jon mackay · #4 (**permalink**) 06-26-2007, 09:56 AM

Ok, There were not any openings near the vent.
Thank you for the information.

Joseph P. Hagarty · #5 (**permalink**) 06-26-2007, 08:21 PM

How about this one?

Bob Harper · #6 (**permalink**) 06-26-2007, 10:29 PM

This is a Heatilator gas direct vent fireplace with their listed trapezoid termination. This cap requires a 30" clearance to a vinyl soffit or 18" to metallic or wood soffit. If you are worried about bumping into this hot termination, they make a shield called a "cool-add'. They make a sconce shaped cover called a DRC-radius, which also shields it some. Otherwise, everything I can see from here looks fine.

Eric Shuman · #7 (**permalink**) 06-27-2007, 09:11 AM

I think the (appropriate) heat shields or cages are a great idea and typically recommended them if the vent could be touched by just walking up to it. These things do get hot and I have seen them installed at the height where children could easily touch them.

Robert Schenck · #8 (**permalink**) 06-28-2007, 05:55 PM

As with Joseph, I’ve come across the same situation a few times. I’ve tried finding an IRC (2003) that pertains to a fireplace flue exhausting so close to a high-traffic area, but had no luck. From what I read here, it sounds as though there is no code, other than the manufactures recommended clearances.

Since I didn’t know of a code, and didn’t have the Mfr’s installation instructions, ….. I just used my CSC (Common Sense Code), and that’s recommending to the client to keep the area clear by at least 18 – 24 inches. He agreed, said good idea, and we moved on. If someone knows the code for such a set up, please pass it on ? Thanks !

Bob Harper · #9 (**permalink**) 06-28-2007, 08:33 PM

Robert, you have three basic concerns with these terminations:
1) Function--it has to breathe for the appliance to work properly. It you restrict the airflow too much, such as with metal deflectors or plants, it may experience operational problems including but not limited to: sooting, lazy flame, delayed ignition, shattered glass and deoxygenation.
2) Exhaust- the hot exhaust needs to go somewhere that it doesn't cause problems. They can easily melt siding and soffits or nearby patio furniture. That rack thing over the vent in your pic is in for trouble.
3) Thermal burns- These things get hot! That's why we call them FIRE PLACES. There is FIRE in that PLACE! ;-) You wouldn't believe how many homeowners don't get that point. I've measured flue gases in excess of 600F on some units.

The gas codes have charts that are default clearances in lieu of the mfrs. listed instructions. The main clearance they show that would apply is the 7ft. clearance above a Public walkway--private walks don't count. Apparently, its ok to bonk your own head as long as you don't do it to neighbors.

Little boys love these teminations. They bounce balls off them smashing the deflectors causing the above noted problems, stuff their sister's dolls into them, tennis balls, weeds--you name it. I've also seen them covered with vines to where they can't breathe. Then there is everybody's favorites--building combustible decks and fences in direct contact with them or directly over them. A clear violation of the 6 'P's: Prior/ proper planning prevents P*** poor performance.

Dale W. Feb · #10 (**permalink**) 07-10-2007, 09:34 PM

Hey Bob,
I have a question regarding the enclosure shown on Joseph Hagarty’s post. Do the testing standards provide a wood framed enclosure (roof deck) across the top of the unit? It has been my experience that the capture of heat increases the odds of a structure fire. What is the framing format for the test?

Bob Harper · #11 (**permalink**) 07-10-2007, 10:01 PM

Most mfrs. will state a clearance to a soffit such as 18". They may even go so far as to differentiate btw a ventilated vs. unventilated soffit and again a wider clearance for plastic (vinyl). What is Not well disseminated is the reference point. Look at Joe's second pic. There is a short overhang of shingles but that is not technically a "soffit". Another area of concern is any trim. There is a fascia board covered with aluminum coil stock. However, this extends about one inch out from the face of the chase wall. Good luck trying to get a ruling from a mfr. on this. I've tried with about 3 other than the one I used to work for (which was three brands itself). They just won't commit to a straight answer. I think this is an area that listings should be specific on. There should be a graph indicating the clearances per amount of extension from the wall, similar to mantel clearances. However, testing for those temps and clearances takes a lot of time. Even then, exterior temps. are at the mercy of winds. You can have 130% clearance but be situated in an area that gets a tunneling effect of wind btw houses and it melts vinyl siding 3 feet away at a 10:00 O'clock/ 02:00 O'clock orientation. Go figure.

Yes Dale, it doesn't take much to trap heat off those terminations. We used to have round terminations that could be extended well out past soffits but they did away with them. Grrrrr.

BTW, even if you don't see signs of heat effect at that fascia board/ shingles, you can still be getting recirculation of flue gases back into the home.

Bob Harper · #12 (**permalink**) 07-10-2007, 10:25 PM

Here are a few shots showing a typical test setup. You can see the 3/4" plywood painted flat black with the seams taped and thermocouples every 6" plus at critical points. There is a stainless flex hose in the vent termination for sampling flue gases. Note the different width mantels. I'm looking for another pic showing a stairstep mantel full of thermocouples.

Once it passes this test, they extend the venting about 20 feet to the side with the vent boxed in and take readings for several days under various conditions. If all that passes, they move on to the wind tunnel, pressure house, etc.

As for exterior temps., they measure much the same as a mantel. It cannot rise more than 117F above the ambient test room temp. Not a fool proof system but at least you have some test data to hang your hat on unlike masonry fireplaces.

Enjoy!
Bob

Joseph P. Hagarty · #13 (**permalink**) 07-11-2007, 11:52 AM

Bob,

What is your opinion with regard to this installation.

Bob Harper · #14 (**permalink**) 07-11-2007, 07:00 PM

Joe, it depends on the listed instructions. This appears to be an HHT product such as Heatilator, Heat& Glo or Quadrafire. Most of their units, but not all, allow for a 6" clearance to an inside corner and 18" to a soffit/ 30" to vinyl soffit. With the model and serial number, a quick call or email to their Technical Services could confirm the clearances, mfg. date, and through which distributor that unit was sold. BTW, those clearances are measured from the trapezoid part and not the base pan itself.

As for the black stains, I would state the Black Particulate staining on the siding and soffit is not a normal occurance and needs to be evaluated by a qualified technician trained to service this brand. What does the inside look like? Glass all sooted up? Are there any signs of Black Particulate all over the home?

What area was this located in? Feel free to drop me an email on the side if you think they need my services.

Take care,
Bob

Joseph P. Hagarty · #15 (**permalink**) 07-11-2007, 07:16 PM

Bob,

Unit was a Heatilator. I do not have an interior photo available for that Inspection.

Deficiencies with regard to the excessive soot production and accumulation at the soffit were noted for further review and repair.

As the Inspection was for a Buyer, I generally do not receive followup correspondence as to what was discovered and/or the repairs that were made.

Email me your business contact info so I will have it available in my database for Client referals.