Side Wall Vent Chimneys & Flues - Direct-Venting Heating Appliance Chimneys & Flues

Direct Vent Chimneys & Fireplaces: guide to choosing, installing, & troubleshooting through-wall or side-wall venting exhaust devices for heating appliances like oil or gas fired boilers, furnaces, or water heaters - Photos & examples of sidewall venting or direct venting installations that are improper and/or unsafe; Side Wall Power Vent Equipment for Gas Fired Boilers, Furnaces, Water Heaters
- DEFINITIONS of Sidewall or Vertical Direct Venting compared with Direct Exhaust;
- DIFFERENCES Between High Efficiency Condensing Boiler vs a Mid-range or Conventional Heater Venting Requirements
- CLEARANCE REQUIREMENTS for Direct Vented Gas Appliances
- SLOPE REQUIREMENTS for direct-vented chimneys & plastic vents
- Safety Warnings Regarding Combustion Air Supply Source for Direct Vented Heating Boilers/Furnaces
- Suppliers of Side Wall or Through Wall Vent Chimney Systems & Equipment - where to buy it
Questions & Answers about the installation or diagnosis of sidewall vent or direct vent chimney or flue exhaust systems for heating appliances: oil, gas, other fuels firing heating appliances & fireplaces
References

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InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

This article describes side wall vent systems for conventional & mid-range-efficiency heating boilers, furnaces & water heaters. We include for comparison, low temperature side wall vent systems used by high efficiency or condensing boilers, furnaces & water heaters. We explain the difference between side wall or direct venting for conventional/mid-range efficiency oil or gas burning heaters and side wall vented high efficiency condensing heating appliances. Contact Us by email if you are having trouble finding the information you need.

Guide to Direct Vent or Side-Wall Vent Chimneys & Flues

Direct-venting or side wall vent chimney and flue systems are a method of venting the exhaust gases from a heating appliance directly out through the side wall of a building while eliminating the need for a vertical chimney of any sort. Gas or oil fired side wall power venters are provided by several manufacturers listed at the end of this article.

Side Wall Vent Equipment for Oil Fired Boilers, Furnaces, Water Heaters

For safe and clean sidewall venting of oil fired heating equipment the vent system incorporates a power vent fan to assure that gases leave the building side wall with sufficient velocity to avoid sooting or otherwise harming the wall. The system, such as Tjernlund's SIDESHOT® series of power vents draws outdoor air thorough the outer passage(s) of a multi-walled vent plenum, cooling the exhaust gases as they pass through the vent.

Risk of fire and heater malfunction with improperly installed or site-built side wall vent systems

One look at the "do-it-yourself" attempt at side wall venting (photo at left) makes clear why the proper equipment is needed to vent an oil fired appliance directly though the building wall. Avoid a building fire with do-it-yourself though-wall chimneys & flues

Our soot stained wall photo (photo at left ) shows what happens at a direct-vented oil-fired heating system when there are multiple errors and unsafe conditions including:

The heater is not working properly and needs immediate service as it is blowing thick dense sooty smoke

The through-wall metal flue vent and "chimney" appears to be a home-made adaptation rather than a listed and approved direct-vent device.

The effects of this home made direct-vent "chimney" are quite visible: the siding on the building has been thickly coated with soot. If you (click to) enlarge the photo you will also see some interesting reverse thermal tracking effects marking the wall studs. This is an unsafe installation that needs immediate repair.

Watch out: the photograph above illustrates an unsafe thorough-wall vent for an oil fired heating appliance. See SOOT on OIL FIRED HEATING EQUIPMENT for more information. We have received or read building owner complaints that sidewall venting has "ruined the building siding" or "stained the siding" but in our OPINION such problems occur because of an improper installation or improper heating equipment maintenance.

Side Wall Power Vent Equipment for Gas Fired Boilers, Furnaces, Water Heaters

Our photo at below left shows an Energy Kinetcs oil fired heating boiler vented using an OEM direct vent system. At below right is the exterior wall of the same installation. The stained wall photo (photo at left ) shows what can happen at a direct-vented high-efficiency heating boiler if the vent is not properly sloped through the wall. Condensate accumulates in the vent pipe, dissolves flue gas deposits, and ultimately leaks both outside and back into the equipment.

To repair this mistake the installer will have to disassemble the entire vent system, and either remove a bit of masonry block from the bottom of the present wall opening or change the interior flue vent connector piping to slightly raise the inside end of the through wall vent - one or the other - to obtain proper condensate slope and condensate handling on this equipment.

Direct or Sidewall Vent Conventional Oil or Gas Fired Heater Exhaust compared with a High Efficiency Condensing Furnace or Boiler

Exhaust or venting of heating appliances may be horizontal, direct through a building side wall, or vertical, up through the building roof. But what is the difference between Direct Exhaust and Direct Venting ? Weil-McLain makes the following important distinctions: [10]

Definitions of Sidewall or Vertical Direct Venting compared with Direct Exhaust

Direct Venting uses a power ventilating blower or fan (and in some models a heat exchanger plenum to cool outgoing gases passing through the building wall (sidewall direct exhaust) or roof or through an existing unused chimney through which a vent pipe is passed (vertical direct exhaust). Combustion air for heating boilers or furnaces is drawn from outdoors through a dedicated air intake pipe or duct (the small diameter pipe in the pair at left of our photo below).

Definitions of Sidewall or Vertical Direct exhaust:

Direct exhaust venting draws combustion air from the utility room or boiler room around the heating appliance and vents appliance exhaust out through a building sidewall or through the roof using an approved or listed B-vent, metal chimney, or similar materials. Combustion air is provided to the heating appliance from the space surrounding the equipment.

Sidewall direct exhaust heating appliances

Sidewall direct exhaust uses a B-vent or other listed or approved metal or even plastic flue vent connector and metal chimney materials to vent outgoing combustion gases through a building side wall (sidewall direct vent).

A blower or power vent draws combustion air in to the heater and a power vent pushes exhaust gases out through a separate or dedicated exhaust flue.

The heating appliance vents directly out through a building side wall, powered by natural draft provided by the heating equipment, typically using a single wall metal flue or chimney or a B-vent. This venting method, typically for gas fired boilers, can be used only by certain heating appliance models such as Weil-McLain's CGs boilers excluding the CGs-4E model.[10]

Vertical direct exhaust-vented heating appliances

Vertical direct exhaust is a similar installation to the sidewall direct exhaust vented vertically, typically up through the building roof. This heater venting system, typically for gas fired boilers, is used only by certain heating appliance models such as Weil-McLain's CGs boilers.

Safety Controls at side wall power venters include

A fan proving switch that prevents the heater from operating if the power vent used to operate the side wall vent is not working
A timer control that keeps the power vent operating for a period after the burner has stopped, typically for 45 seconds, to purge remaining combustion gases from the heating appliance

Safety controls and power vents for gas fired heating appliances are certified by the AGA, the American Gas Association.[6]

Image at left courtesy of Carson Dunlop Associates.

Also see CONDENSING BOILERS/FURNACES and CONDENSING BOILERS/FURNACES DAMAGE.

What's the Difference Between Venting a High Efficiency Condensing Boiler or Furnace or Water Heater with a Mid-range or Conventional Heating Boiler, Furnace, or Water Heater?

In comparing the venting of exhaust gases from a high efficiency furnace, boiler or water heater with the venting of exhaust gases from a conventional heating system it will be immediately obvious that the high efficiency equipment exhaust is produced at a low-enough temperature that it is vented through comparably small-diameter plastic piping rather than a cooled, fire-protected metal heating vent.

What can be confusing is that some mid-range efficiency heating equipment may vent through a (larger diameter, say 4") plastic heater vent referred to as HTPV (high temperature plastic vent) chimneys.

We illustrate an HTPV system at below left and a high efficiency plastic direct vent system at below right (Image courtesy of Carson Dunlop Associates). More details about HTPV and a product safety recall are at PLASTIC Plexvent / Ultravent RECALL.

Clearance Requirements for Direct Vented Gas Appliances

Exhaust Vent Termination Clearance Requirements

In a table below we provide a complete list of required clearance distances between the air intake or combustion gas exhaust vents for direct vented heating appliances. Illustration adapted from Thermo Products installation instructions - click to enlarge this or any other image or photo at InspectAPedia. [15]

Some highlights include:

The exhaust vent terminal shall be located at least 3-feet above any forced air inlet located within 10-feet. See [the figure below] for a depiction [courtesy of Thermo Pride] of the minimum required clearances between vent terminations and building features according to the National Fuel Gas Code (NFGC).[19]
The vent terminal shall be at least 12-inches below, 12-inches horizontally from, or 12-inches above, any door, window, or gravity air inlet into a building. The bottom of the vent terminal shall be located at least 12-inches above grade.
The exhaust vent terminal shall not be located:
- over public walkways or over an area where wetting of surfaces by condensate, or water vapor, could create a nuisance or hazard,
- near soffit vents, crawl space vents, or other areas where condensate or water vapor could create a nuisance, hazard, or cause property damage, and
- where wetting of components by condensate, or water vapor, could be detrimental to the operation of pressure regulators, relief valves, or any other equipment.
The vent terminal shall be installed a minimum of 14-inches from any obstruction and 3-feet from an inside corner of an L-shaped structure (see table below).

NFGC Recommended Clearance Distances from a Direct Vent Gas Appliance Terminal to Other Building Features
	Direct vent gas exhaust termination item clearance	Distance required (U.S.)
	Distance above grade (ground surface), balcony, deck, porch, veranda	12 inches [note that in areas of deep snow this clearance may be inadequate and thus unsafe]
	Distance to a window or door that is operable (can be opened)	12 inches [Note 2]
	Distance to a permanently closed (or non-operable) window	12 inches [Note 3]
	Distance to a ventilated soffit (roof eaves, overhang) above the vent terminal & within a horizontal distance of two feet from the centerline of the terminal	24 inches [Note 3]
	Distance to an un-vented soffit	24 inches [Note 3]
	Distance to outside corner of the building	24 inches [Note 3]
	Distance from the vent centerline to a building inside corner	3 feet [Note 3]
	Distance to each side of centerline extended above a [gas] meter / regulator assembly	4 feet [Note 3]
	Distance to a [gas] service regulator vent outlet	4 feet [Note 3]
	Distance to a non-mechanical air supply inlet to the building or to the combustion air inlet for any other appliance	12 inches [Note 2]
	Distance to a mechanical [systems] air supply inlet	3 feet above if within 10 feet horizontally
	Distance above a paved sidewalk or paved driveway on public property	7 feet [Note 4]
	Distance below a balcony, deck, porch, veranda	24 inches [Note 3]

Notes: 1 Authorities/Sources: National Fuel Gas Code, ANSI Z223.1 / NFPA 54 [8] Gas Fired High Efficiency Furnace Down Flow & Direct Vent (Sealed Combustion) Thermo Pride Model CMA1-50N & CMA2-75N Installation and Service Manual" [15] [cites & recounts illustrations & clearances from the U.S. National Fuel Gas Code 2. For non-direct vent applications such as the side-wall vent appliance shown earlier on this page, the required distance is much greater: 4 feet to the side or below the opening, or 1 foot above the opening. 3. This distance requirement may vary in order to be in accordance with local building codes, the gas supplier, and the equipment manufacturer's own product installation specifications 4. In direct vent applications, this clearance distance must be in compliance with local building codes, the requirements of the fuel gas supplier for the heating appliance in use, and the appliance manufacturer's instructions. For non-direct-vent applications (that is, side wall venting only), the required clearance is 7 feet.

Importance of Proper Slope on Heating Equipment Exhaust Vent Piping & Protection from Blockage by Snow, Ice, Shrubs or Wind

Our illustration at left shows the plastic pipes of two types of direct vent heating appliances protruding through a building sidewall.

We can tell from the height above ground that the heaters are most likely located in the building basement.

The pair of plastic lines in the left of the photo are an air intake (the shorter protruding plastic pipe) and exhaust vent outlet (the longer plastic outlet pipe). The wider single round plastic vent at the right side of our photo is venting a second appliance, perhaps a water heater.

Watch out: We cal also see that as with the gas appliance power vent shown in the previous section, this high efficiency heating system condensate is also not being properly drained from the left hand condensing heater - instead of condensate running back into the building and into a building drain, this pipe is sloped so that condensate runs out of the end of the plastic vent line.

The problem with this arrangement becomes evident in cold weather as condensate freezes and the ice formed can actually block the safe venting of exhaust gases.

Watch out: Ice formation at sidewall vents is not the only cold weather hazard for this equipment. Our photo at left shows that the vents are less than 24 inches from the ground. In climates where snowfall may occur at depths capable of covering the air intake or sidewall vent outlet, Vermont Gas and Thermo Products both warn that it is critical to keep sidewall vents clear of snow-cover. Blocking the combustion air intake or exhaust outlet by accumulated snow, ice, or even shrubs or piled leaves can result in dangerous. potentially fatal carbon monoxide gas poisoning of the building occupants.[13][15]

You should inspect the exhaust vent and combustion air intake vent for blockage at least annually, and we recommend further inspection in winter for blockage by snow or ice:

The vent and combustion air terminations shall be checked periodically, at least at the start of each heating season, for restriction or blockage from foreign material in the exhaust vent or in the air intake piping. Clean the air intake and vent terminations when necessary. [15]

Protect direct vented appliance vents from becoming blocked by snowfall

As you can read in our citation of direct vent and sidewall vent clearance distance requirements in the FAQs below,

The outlet/inlet of the vent and air intake terminations shall be a minimum of 12 inches above highest anticipated snow level. The vent outlet must be installed a minimum of 12 in. above the air intake inlet.

Terminations must also be kept clear of any leaves, weeds, combustible materials, snow, and ice build-up. [15]

and Thermo Products further recommends:

In geographical areas with considerable snowfall, it is advisable to locate the vent terminal much higher than the minimum 12-inches above ground to prevent blockage by snow accumulation or drifting. [15]

For at least some heating appliances and manufacturers, and to solve vent clearance difficulties when your installation cannot meet the specifications in the Gas Code, manufacturers' specifications, or local building codes, roof vent termination kits are available. Notice that the illustration (left) of roof-vent termination of direct-vent appliance air intake and exhaust does not show the necessary flashing & sealing to avoid roof leaks. Illustration adapted from Thermo Products installation instructions. [15]

The furnace may be vented vertically through the roof. The outlet/inlet of the vent and air intake terminations shall be a minimum of 12 inches above highest anticipated snow level. The vent outlet must be installed a minimum of 12 in. above the air intake inlet. The combustion air intake shall be installed upwind of the vent outlet when exposed to prevailing winds. The exhaust vent and combustion air intake can be a minimum of 3 in. and a max. of 24 in. apart. [15]

Watch out: when chimneys or vents pass through building floors and roofs above, additional fires stopping may be required.

Protect direct vent appliances from wind:

Wind protection for direct vent appliances - Thermo Products Installation Instructions

The combustion air intake shall be installed upwind of the vent outlet when exposed to prevailing winds.

Avoid locating the vent terminal on a wall facing prevailing winds and wide-open areas.

When impractical, choose a location that protects the vent from strong winds, such as behind a fence or hedge. [15]

Comment: Keep hedges, fencing, or other wind barriers far enough away from the air intake vent to avoid obstructing air intake, and keep hedges far enough away to avoid plant injury from the heat of exhaust gases.

Illustration adapted from Thermo Products installation instructions. [15]

Avoid locating the vent terminal over areas where dripping of condensate, or small pools of acidic condensate, could create a problem. [15]

Comment: OPINION: an exhaust vent that is dripping condensate to the outdoors in freezing climates risks dangerous blockage by ice formation.

Safety Warnings Regarding Combustion Air Supply Source for Direct Vented Heating Boilers/Furnaces

Weil Mc-Lain [10], Thermo Products [15] and other manufacturers warn that if the heating appliance is in an area where local indoor-area-supplied combustion air is likely to be contaminated the installer must pipe an outdoor combustion air supply to the heating boiler (or other heating appliance) combustion air intake port.

Watch out: There are critical concerns with combustion air contamination for heating appliances:

Combustion air that is contaminated with corrosives can damage the boiler by corroding the heat exchanger or other components. The result can be worse than damage to the equipment. Corrosion that leads to flue gas leaks can leak potentially fatal carbon monoxide or other gases into the occupied space of the building.

Other combustion air contaminants that are flammable or themselves combustible could lead to an actual fire or explosion.

Examples of corrosive contaminants include

Spray cans containing chlorocarbons or flurocarbons
Permanent wave solutions (is your heating equipment installed in a beauty parlor /)
Chlorinated waxes or cleaners
Calcium chloride such as snow and ice melting "salts"
Sodium chloride (salt) used in water conditioners (water softeners)
Chlorine and other swimming pool chemicals (is your heating equipment installed near an indoor swimming pool?)
Some refrigerant gas leaks (most refrigerants are inert gases but some, such as ammonia, are highly corrosive)
Paint or varnish thinners or removers
Cements or glues
Anti static fabric softeners used in clothes dryers
Chlorine based bleaches, laundry detergents, cleaning solvents
Adhesives & glues such as tile mastic, carpet glue, even self-stick floor tiles or similar products

If your building contains any of these or other corrosive or explosive products and if you cannot remove them from the locale, an outside combustion air supply must be piped to the heating appliance air intake.

Watch out: also make sure that the combustion air supply outdoors is not itself close to a source of corrosive or explosive materials.

List of manufacturers of Side Wall or Through Wall Vent Chimney Systems & Equipment

Direct sidewall vent heating appliance manufacturers & products can be listed here at no fee. CONTACT US to provide information or technical comment.

Gas fired commercial water heater power venters, Bradford White, Field Controls, Model SWGII-5-6 and SWG-8 provide sidewall venting for commercial water heaters (290K BTUH to415K BTUH) [Copy on file as /Side Wall Power Vents/Gas_Heater_WalL_Vent_Bradford_White_Field.pdf ][7]
"Gas Side Wall Power Venters", Tjernlund Corporation, provides GPAK gas vent packages that combine a power ventilation system and a 4" draft control including appropriate safety controls.This product can vent gas fired appliances at up to 250K BTUH. Website: tjernlund.com/gassidewall.htm [5]
"Oil Side Wall Vent Systems", Tjernlund Corporation, provides SS2 SideShot sidewall vent systems for oil fired heating boilers, furnaces or water heaters. The equipment includes a multi-walled plenum that uses outdoor air to cool the exhaust gases as they pass through the building wall, and can be installed with zero clearance to combustible materials such as wall studs or siding. As with the gas side wall power venters described above, the unit includes a factory-wired safety control that will prevent the heater from operating if the power vent is not working. This equipment can safely vent heating appliances up to 315K BTUH (with a flame retention oil burner. Conventional oil burners on older equipment limit the BTUH handling capacity of the vent to a maximum of 223K BTUH.[6]
"Mighty Venter Power Vent System", Laars Models MV2, MV2, MV4, MV5 for Mighty Therm 5009-1825. Bradford White Corporation [11]
"SWG/CV Power Venter, outdoor mounted power venters for oil or gas fired heating equipment", Field Controls. This power vent device mounts on the exterior of the building and operates when the indoor room thermostat calls for heat. Like the other sidewall power vent systems for heating equipment, the Field Controls Power Venter includes additional safety controls to prevent the heater from operating if the vent does not turn on. [13]
"Tankless water heater side wall vent termination", Rheem Corporation, [9]
"Sidewall or Vertical Direct Vent or Direct Exhaust" systems for gas fired water boilers are provided by Weil McLain for Weil McLain's Gold™ CGs Gas-Fired Water Boilers [10]

Listed special gas vent systems that comply with UL-1738 & UL S636 and in Canada, certified by CSA are the only vent systems that can be used with Weil Mc-Clain's CGs heating boilers. Depending on the brand and model, your heating appliance may have similar restrictions so be sure to read the installation instructions with care.

Heat-Fab Saf-T- Vent®
Flex-L International Inc. StaR-34
Z-Flex, Inc. Z-Vent II
Pro Tech Systems FasNSeal™

Frequently Asked Questions (FAQs) about Sidewall Vent Equipment for Heating Boilers, Furnaces, Water Heaters & Fireplaces

Question: is it ok to install an elbow on the outside plastic direct-vent exhaust to avoid ice problems?

I see by the photo of ice on the exhaust pipe, that the installation is not sloped back into the furnace, or that it may not be high enough. Can the pipe be best elbowed on the outside, slanted back into the house, while extensions are on the exhaust pipe well above snow levels. And what about insulation in an unheated crawl space and a heat tape. Then there are testing for improper gluing of the elbows and round connectors of PVC piping. How should they be tested for no leakages. - Concerned2 11/20/2012

Reply: No

Concerned,

I am nervous about your pipe elbowing in the exterior as I think it violated the manufacturers instructions, and increases the freeze risk too by adding more travel distance through freeze temperature piping - but I may have misunderstood.

The pipe needs to be re set to proper slope to fix the freeze problem

Tests for leaks in a PVC condensate drain can be done using pressure fittings and plugs but I doubt anyone does that, relying more on workmanship during installation and inspection for leaks afterwards.

Too I agree that a condensate drain routed through a freezing crawl space would be unsafe. I would not rely on heat tapes, rather the installation sounds off.

Reader follow-up:

I live in B.C. I do not know who was to be held accountable when the installation of my Lennox Pulse was not inspected by the gas inspector, back in 1994. A trouble area inside the house, just before the exhaust PVC pipe was to go outside, there was placed four connectors, close together, up in the beam or joist area of the house. They did this to have the pipe on the outside 12 inches above snow level, which is not sufficient for this area.

One elbow became detached.No one in the gas industry would come to fix a Lennox Pulse G21, claiming if they did so, it would void the warranties. The installer would not inspect the pipe. The permit was taken out, but no inspector came to investigate, and there seems to be no one investigating how pvc pipe is installed to a high efficiency gas furnace. I went from 1995-1996, after the detached pipe was noted by guests reporting they were feeling sick in the bedroom above this venting. The problem was that no one would come because it was Lennox G21 H-EF. The other companies were declaring they did not know how to work on a Pulse, or testing piping or the heat exchanger.

that there were so many elbows in a small area, less than 15 inches, between the beam and the outside house what Code or instructions from the manufacturer were being violated, and how do you deal with those involved?
Rather than fixing the problem on May 3, 2012, another Lennox dealer, instead of my request one straight pipe, a correction of that area, he, too, put in two elbows on the inside area, up in the beams. I asked for a straight pipe and the elbows on the outside of the house.

He left the premises not pressure testing the piping system or the heat exchanger as requested.
He put in 90 percent new replacement piping, when the only area was of less than two feet. He said he did a visual inspection for the heat exchanger, knowing the exchanger was 18 years old, and the new piping could yet have a problem of leakages.
What all codes may have been violated? - Concerned 12/2/12

Reply:

Concerned: note the with respect to clearances between the direct vent and the ground surface, the distance shown is a minimum not a maximum allowable distance. But in relocating the exhaust or intake openings, keep in mind that other safety clearances from windows etc. must still be respected. The instructions to which you refer include the following additional details that address your concerns:

The outlet/inlet of the vent and air intake terminations shall be a minimum of 12 inches above highest anticipated snow level. The vent outlet must be installed a minimum of 12 in. above the air intake inlet. The combustion air intake shall be installed upwind of the vent outlet when exposed to prevailing winds. [15]

Question: Strong winds may overcome exposed direct vent chimneys or flues for heating appliances?

Concerning sidewall power vent to one of my residential gas furnaces. It is a proper code compliant side vent sloped properly with condensate drain etc. However, it is on a wall exposed to a wide open area - thus winds can be strong against the house. Do I need to install something like an open vent collar to reduce the back pressure variations caused when winds are heavy? - Sack from VA 12/2/12

Reply:

Sack

Interesting question, I don't know but if you can tell us equipment brand and model we will research the question - or you can all the the manufacturer who can tell us.

I've never seen a power vent with wind protection installed, and we have presumed that the blower fan that provides positive draft for the direct-vented heating appliance is designed & tested by the manufacturer to provide more than adequate draft provided that you have followed the manufacturer's installation instructions. Those instructions typically state that

The combustion air intake shall be installed upwind of the vent outlet when exposed to prevailing winds.

Avoid locating the vent terminal on a wall facing prevailing winds and wide-open areas. When impractical, choose a location that protects the vent from strong winds, such as behind a fence or hedge. [15]

Do you have a copy of the installation instructions and can you give the brand and model of your heating appliance?

Question: what is the required clearance between adjacent houses & a neighboring direct vent fireplace?

Is there a minimum distance between brick houses in Toronto for venting termination of a fireplace using direct vent? - A.W., 12/30/2012

Reply:

I have not found building code citations that refer to nearby or adjacent buildings when specifying clearances for direct vent fireplaces, but it seems likely that your local building code inspector would agree that the clearance requirements for the building in which the fireplace is installed would set the minimum acceptable clearances that would then apply also to a nearby or adjacent building.

In other words, if the fireplace vent distances and position relative to your own building windows or doors were LESS THAN those to the windows & doors on the building where the fireplace is installed, and presuming for a moment that the fireplace was installed properly, meeting local building permit and code requirements, then a violation probably exists.

If the fireplace vent distances and position relative to your own building windows and doors is GREATER THAN those to the windows and doors where the fireplace is installed, and presuming for a moment that the fireplace was installed properly, meeting local building permit and code requirements, then a violation probably does not exist.

Take some some sharp photos of the installation that concerns you, or make a sketch and send those along and we may be able to comment further.

Thanks to Alan Carson, Carson Dunlop Associates, Toronto, for assistance with this topic. .

...

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Technical Reviewers & References

Related Topics, found near the top of this page suggest articles closely related to this one.

Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. (416) 964-9415 1-800-268-7070 info@carsondunlop.com. The firm provides professional home inspection services & home inspection education & publications. Alan Carson is a past president of ASHI, the American Society of Home Inspectors. Thanks to Alan Carson and Bob Dunlop, for permission for InspectAPedia to use text excerpts from The Home Reference Book & illustrations from The Illustrated Home. Carson Dunlop Associates' provides:
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[2] Carrier Model BW9 Gas-Fired Condensing Boiler - Gas Fired Direct Vent Condensing Boiler - Example Installation & Operating Manual
[3] "Instructions for Installing FIELD Type AF Barometric Draft Controls," Form No. 31 DC 30666, Field Corporation, Mendota, IL 61342, web search 04/02/2011, original source: http://www.fieldcontrols.com/pdfs/04592700.pdf, Field Controls, Kingston, North Carolina 28501, Tel: 919-522-3031
[4] Tjernlund Draft Controls, A Series (single action for oil, solid fuel, and fan-assisted gas burners) and B Series (double action for gas heating appliances), web search 04/02/1011, original source: http://www.tjernlund.com/Tjernlund_8500490.pdf , Tjernlund Products, Inc., 1601 Ninth Street, White Bear Lake MN 55110-6794, Tel: 651-426-2993 or 800-255-4208 website: www.tjernlund.com Email: fanmail@tjfans.com
[5] "Gas Side Wall Power Venters", Tjernlund Corporation, 1601 9th Street White Bear Lake, MN 55110-6794 Tel: 800-255-4208, Website: tjernlund.com/gassidewall.htm, Quoting:
Side Wall Vent Systems save time and money and are excellent for electric to gas/oil, renovations, new construction or for replacing deteriorated chimneys. Side wall venting saves costly materials and labor on two, three or more story runs. It also increases living space by cutting out interior chases. Proven safety interlocks assure proper exhaust, a feature conventional chimneys do not offer in today's homes and buildings.
[6] "Oil Side Wall Vent Systems", Tjernlund Corporation, 1601 9th Street White Bear Lake, MN 55110-6794 Tel: 800-255-4208, provides SS2 SideShot Wall Vent System. Website: .tjernlund.com/oilsidewall.htm Quoting:
The SideShot® models SS1 and SS2 SideWall Vent Systems include the UC1 Universal Control ... [ and are ] designed for oil fired heating equipment or a deluxe gas vent system. Factory wired safety and operating controls allow simple interlock with any burner. ... SS2 features a self-cleaning stainless steel, backward inclined impeller and sealed ball bearing motor for virtually maintenance free installations.
- Tjernlund Corporation also provides a Sidewall Venting sizing tool for oil fired heating equipment (www.tjernlund.com/Sizing/Oil.htm) and a separate tool for gas fired heating equipment (www.tjernlund.com/Sizing/gas.htm) .
[7] Bradford White Sidewall Power Venter Kit, Field Controls, Tel: 252-522-3031, Website: www.fieldcontrols.com
[8] National Fuel Gas Code (Z223.1) $16.00 and National Fuel Gas Code Handbook (Z223.2) $47.00 American Gas Association (A.G.A.), 1515 Wilson Boulevard, Arlington, VA 22209 also available from National Fire Protection Association, Batterymarch Park, Quincy, MA 02269. Fundamentals of Gas Appliance Venting and Ventilation, 1985, American Gas Association Laboratories, Engineering Services Department. American Gas Association, 1515 Wilson Boulevard, Arlington, VA 22209. Catalog #XHO585. Reprinted 1989.
[9] "Tankless water heater side wall vent termination", Rheem Corporation, Website: http://www.rheem.com/products/tankless_water_heaters/
how_to_install/side_wall_vent_termination_10/
[10] "Gold™ CGs Gas-Fired Water Boilers Venting Supplement: sidewall direct exhaust, vertical direct exhaust, sidewall direct vent, vertical direct vent models
[11] "Mighty Venter Power Vent System", Laars Models MV2, MV2, MV4, MV5 for Mighty Therm 5009-1825. Bradford White Corporation, U.S. 20 Industrial Way, Rochester, NH 03867 • 603.335.6300, Canada, 1869 Sismet Road, Mississauga, Ontario, Canada L4W 1W8 • 905.238.0100, Website: www.Laars.com
[12] "Be Alert, Keep Sidewall Vents Clear", Vermont Gas Corporation, P.O. Box 467, Burlington VT 05402 Delivery: 85 Swift St, South Burlington VT 05403. Phone: 802.863.4511. Email: CustomerService@VermontGas.com, web search 4/1/2012, original source: vermontgas.com/winter/vents.html
[13] "Power Venting, SWG/CV Power Venter, ComboVent Power Venter, Field Controls, FIELD CONTROLS, LLC 2630 Airport Road Kinston, NC 28504 Tel: 252.522.3031 Email: sales@fieldcontrols.com
[15] "Gas Fired High Efficiency Furnace Down Flow & Direct Vent (Sealed Combustion) Thermo Pride Model CMA1-50N & CMA2-75N Installation and Service Manual", Thermo Pride, Thermo Products LLC, PO Box 217, North Judson, IN 46366, Tel: 574-896-2133, retrieved 12/30/2012, original source: www.thermopride.com/pdf/mg-508.pdf, copy on file as Thermo_Pride_CMA1-50N_CMA2-75N_Installation_mg-508.pdf
Home Heating System Should Be Checked [for proper venting and for CO Carbon Monoxide Hazards - DJF]
Lennox Pulse Furnace Safety Inspection/Warranty Program: Carbon Monoxide Warning
Domestic and Commercial Oil Burners, Charles H. Burkhardt, McGraw Hill Book Company, New York 3rd Ed 1969.

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Guide to Direct Vent or Side-Wall Vent Chimneys & Flues

Side Wall Vent Equipment for Oil Fired Boilers, Furnaces, Water Heaters

Risk of fire and heater malfunction with improperly installed or site-built side wall vent systems

Side Wall Power Vent Equipment for Gas Fired Boilers, Furnaces, Water Heaters

Direct or Sidewall Vent Conventional Oil or Gas Fired Heater Exhaust compared with a High Efficiency Condensing Furnace or Boiler

Definitions of Sidewall or Vertical Direct Venting compared with Direct Exhaust

Definitions of Sidewall or Vertical Direct exhaust:

Sidewall direct exhaust heating appliances

Vertical direct exhaust-vented heating appliances

Safety Controls at side wall power venters include

What's the Difference Between Venting a High Efficiency Condensing Boiler or Furnace or Water Heater with a Mid-range or Conventional Heating Boiler, Furnace, or Water Heater?

Clearance Requirements for Direct Vented Gas Appliances

Exhaust Vent Termination Clearance Requirements

Notes:

Importance of Proper Slope on Heating Equipment Exhaust Vent Piping & Protection from Blockage by Snow, Ice, Shrubs or Wind

Protect direct vented appliance vents from becoming blocked by snowfall

Protect direct vent appliances from wind:

Safety Warnings Regarding Combustion Air Supply Source for Direct Vented Heating Boilers/Furnaces

Examples of corrosive contaminants include

List of manufacturers of Side Wall or Through Wall Vent Chimney Systems & Equipment

Frequently Asked Questions (FAQs) about Sidewall Vent Equipment for Heating Boilers, Furnaces, Water Heaters & Fireplaces

Question: is it ok to install an elbow on the outside plastic direct-vent exhaust to avoid ice problems?

Reply: No

Reader follow-up:

Reply:

Question: Strong winds may overcome exposed direct vent chimneys or flues for heating appliances?

Reply:

Question: what is the required clearance between adjacent houses & a neighboring direct vent fireplace?

Reply:

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Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair