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PLANNING YOUR VENT FREE INSTALLATION
 This product is not intended for use in bedrooms or bathrooms. It may be installed in other areas of the home subject to the sizing guidelines below.

FRESH AIR REQUIREMENTS FOR COMBUSTION AND VENTILATION
Adequate combustion and ventilation air must be provided (see Provisions for Combustion and Ventilation Air below). For detailed requirements concerning air for combustion and ventilation see National Fuel Gas Code ANSI Z223.1-1996 / NFPA 53-1996 Section 5.3.
Provisions for Combustion and Ventilation Air
This heater shall not be installed in a confined space unless provisions are made for adequate combustion and ventilation air.
Modern construction standards have resulted in homes that are highly energy-efficient and that allow little heat loss. Your home needs to breathe. All fuel-burning appliances within it require fresh air in order to function properly and safely.
Other appliances in the home, such as clothes dryers, exhaust fans, fireplaces, and other fuel burning appliances all use the air inside the dwelling. If the available fresh air is insufficient to support the demands of these appliances, problems can result.
The fresh air requirements of this heater must be met within the space where it will be installed. The following information will help you ensure that adequate fresh air is available for the heater to function properly and safely.
Classification of Space For Proper Ventilation
Any space within a home can be classified into one of the following three categories:
1. Unusually Tight Construction.
2. Confined Space.
3. Unconfined Space.
First, determine which classification defines the intended space for installation of this heater.

UNUSUALLY TIGHT CONSTRUCTION
You must provide additional fresh air if the space falls into this classification. Unusually Tight Construction is defined as construction, which meets the following criteria:
a. Walls and ceilings exposed to the outside atmosphere have a continuous water vapor retarder with a rating of one perm or less (one perm = 6 x 10-11 kg per pa-sec-m2. This is a thickness / vapor barrier rating) with openings gasketed or sealed and -
b.Weather stripping has been added on openable windows and doors and -
c. Caulking or sealants are applied to areas such as joints around window and door frames between sole plates and floors, between wall ceiling joints, between wall panels at penetrations for plumbing, electrical, and gas lines and at other openings. If your home meets all of the three criteria above, you must provide supplemental fresh air for the appliance. If your home does not meet the above criteria, follow the procedure below.
Determine If You Have a Confined or Unconfined Space
Use the formula below to determine if you have a confined or unconfined space
Space: Is defined as the room in which you will install the heater plus any adjoining rooms with doorless passageways or ventilation grills between the rooms.
Unconfined Space: Is a space which has an air volume of at least 50 cubic feet for each 1,000 BTU/hr (4.8 m3 per K.W.) input rating for all appliances in the space (cubic feet equals length x width x height of space). Include adjoining rooms only if they are doorless passageways or there are ventilation grills between the rooms.

EXAMPLE: The smallest single room without connecting rooms or grill work to accommodate a 26,000 BTU/hr. appliance is 12'x14'x8' (= 1344 cubic feet which exceeds the minimum of 1300 cubic feet).
Confined Space: Is a space which has an air volume of less than 50 cubic feet for each 1,000 Btu/hr (4.8 m3 per K.W.) input rating of all appliances in the space. Include adjoining rooms only if there are doorless passageways or ventilation grills between the rooms. 1. Determine the volume of space (length x width x height). Include adjoining rooms connected by doorless passageways or ventilation grills.

EXAMPLE: A room that is 9' x 13' x 8' has a volume of 936 cubic feet (length x width x height). An adjoining open kitchen that is 11' x 13' x 8' has a volume of 1144 cubic feet. An adjoining open dining room is 12' x 12' x 8' with a volume of 1152 cubic feet. Add the cubic feet of the 3 adjoining rooms (936 + 1144 + 1152 =3232 cubic feet).

PLANNING YOUR INSTALLATION
PAGE 7 2. Divide the volume of space by 50 cubic feet. The result is the maximum BTU/hr that the space can support.
Example: 3232 divided by 50 = 64.6 (or 64,600 Btu/hr.)
3. Add the BTU/hr. ratings of all fuel-burning appliances installed in the same space, including the following: Gas Fireplace Logs Vented Gas Heater Gas Water Heater Gas Furnace Vent-Free Gas Heat Other Gas Appliance * * Do not include Direct Vent appliance as these use outside air for combustion and vent to the outdoors.
Example: Gas Stove 60,000 BTU/hr. Vent Free Heater + 26,000 BTU/hr. Total = 86,000BTU/hr.
4. Compare the maximum BTU/hr. rating the space can support with the total BTU/hr. used by the appliances.
Example: 64,600 BTU/hr. max. the space can support 86,000 BTU/hr. total used by appliances.
In this example, the maximum BTU/hr that the space can support is less than the total used by the appliances, the space is considered to be a Confined Space. Additional air must be provided to meet the requirements of the Vent Free heater.
A Confined Space may be ventilated in two ways:
A. Open up or provide at least two ventilating grills to an adjoining unconfined space (see below). Each of the two grills must provide an opening of at least 50 square inches with all opening dimensions being at least 3" long. One grill must be located within 12" of the ceiling; the other within 12" of the floor (If the total exceeds 100,000 BTU/hr., additional grills will be required.).
B. Vent the room directly to the outdoors (provide one square inch of opening for each 4,000 BTU/hr). For further information on ventilation guidelines and sizing specifications follow the National Fuel Gas Code NFPA 54/ANSI Z223.1- Latest Edition, Section 5.3. If the total BTU/hr. used by the appliances is less than the maximum BTU/hr., the space is able to support the appliances. The space meets the Unconfined Space criteria and no further ventilation is required.

Sizing a Gas Stove:

Gas stoves range in heating ability. A 32,000 BTU input stove heats up to 1300 sq ft. The larger stoves go up to 45,000 BTU’s input, and heat up to 2000 sq. ft. However, the heating ability is not reliably determined by the BTU input figure provided, but rather the BTU output that you must calculate to determine. Simply multiply the BTU input by the Annual Fuel Utilization Efficiency*, (AFUE). This gives the output. This important fact is not provided in the literature, and is necessary to consider before determining a stove’s heating ability.

Here is an example to illustrate:
A vent-free stove has a 99% AFUE (Annual Fuel Utilization Efficiency), so the output of a 32,000 BTU input stove is 31,680 BTU’s (0.99 X 32,000). The same 32,000 BTU input ‘Direct’ or ‘B’ vented stove with a AFUE of 62% has a much lower heat output rating 19,840 BTU’s (0.65 X 32,000 BTU’s).

Conclusion: Both stoves have the same input BTU fuel consumption, but the heat output is quite different. Vent free stoves on average save you 25% on your fuel bill, cost less for the same stove shape/color, and save approx $650 less too install. They have a proven safety track record of over 10 years.


Meeting ‘In Person’:
This website provides accurate photos and information and works as well as a showroom, and I’m just a phone call away. Some express an interest to visit, which I welcome. However, I am out most nice weather days doing chimney work. I’m available some days and always evenings by appointment, 5 to 9pm, or days by chance with at least 15 minutes notice. (cell 401-249-1818)


Installers Corner...
I’m a highly skilled college educated engineer with 17 years experience in installations, am well known in all of southern RI, and hold a perfect standing with the better business bureau. However, the state allows homeowners to pull a permit and install. My ‘do-it-yourselfer’ customers find the task easier than they thought, and receive free installation tech assistance by calling my cell at 401-249-1818. When finished, you confirm the job meets code by the easy to follow guidelines in stove owners manual. This manual is the sole resource the building inspecter refers to when he inspects, so there are no surprises. You’ll save the $350 to $700 labor fee, and find our quality installation parts as steeply discounted as the stoves.

Important Warranty Information:
Stove manufacturers never do warranty service. We, the retailer, must honor warranties as a condition to sell a product line, but don’t for stoves bought elsewhere. For the short busy season, a warranty tech has more installation work than he can handle at up to $100/hr., but loses 4-5 hours for the mere $40. warranty reimbursement. That’s a half day lost, and typically consists of two service calls...one to diagnose, another to repair. Then there’s office work...ordering parts and claim forms with copies of receipts, etc.. It’s easier now to understand now why your warranty is worthless if you purchased from some place too far away to come to your home, let alone twice. We gladly service all stoves we sell, and have been since 1990.

Kind Regards,
John Debar


*The AFUE efficiency for vented stoves is always significantly lower than the efficiency stated on the brochure.