CFM UVHK31MP Benutzerhandbuch

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Provisions for Adequate Combustion and Ventilation Air
WARNING:  This heater shall not be installed in 
a confined space or unusually tight construc-
tion unless provisions are provided for adequate 
combustion and ventilation air.
Today’s homes are built more energy efficient than ever.  New 
materials, increased insulation and new construction methods 
help reduce heat loss in homes.  Home owners weather strip 
and caulk around windows and doors to keep the cold air out 
and the warm air in.  During heating months, home owners 
want their homes as airtight as possible.
While it is good to make your home energy efficient, you need 
fresh air.  All fuel-burning appliances need fresh air for proper 
combustion.
Supplying Adequate Ventilation
This appliance must be installed in an unconfined space.
The following information will help you classify your space and 
provide adequate ventilation for complete combustion.
An Unconfined Space has a minimum volume of 50 cubic 
feet for each 1000 BTU/Hr input rating of all appliances in the 
space. (4.8 M
3
 per kw), (cubic feet equals length x width x 
height of space).
A Confined Space has a volume of less than 50 cubic feet for 
each 1000 BTU/Hr input rating of all appliances in the space, 
(4.8M
3
 per kw), (cubic feet equals length x width x height of 
space).
Determining if You Have a Confined or Un-
confined Space
Use this worksheet to determine if you have a confined or 
unconfined space.
Space:  Includes the room in which you will install heater plus 
any adjoining rooms with doorless passageways or ventilation 
grills between the rooms.
1.  Determine the volume of the space (length x width x height).
 
Length x Width x Height = _____cu. ft. (volume of space)
 
Example: Space size  25’ (length) x 25’ (width) x 8’ (ceiling 
height) = 5,000 cu. ft. (volume of space)
 
If additional ventilation from adjoining room(s) is supplied 
with grills or doorless openings, add the volume of these 
rooms to compute the total volume of the applicable space.
2.  Divide the space volume by 50 cubic feet to determine the 
maximum BTU/Hr the space can support.
 
________(volume of space) ÷ 50 cu. ft. = (Maximum BTU/
Hr the space can support.
 
Example:  5,000 cu. ft. (volume of space) ÷ 50 cu. ft. = 100 
or 100,000 (maximum BTU/Hr the space can support)
3.  Add the BTU/Hr of all gas burning appliances in the space.
 
 
Gas range 
BTU/Hr
 
 
Vented gas heater 
BTU/Hr
 
 
Gas fireplace logs 
BTU/Hr
 
 
Other gas appliances*  +  BTU/Hr
 
 
Total                              =  BTU/Hr
 
Example:  
Gas range 
  60,000 BTU/Hr
 
 
Vent-free logs 
+  29,000 BTU/Hr
 
 
Total 
=  89,000 BTU/Hr
*Do not include direct-vent gas appliances.  Direct-vent draws 
combustion air from the outdoors and vents to the outdoors.
4.  Compare the maximum BTU/Hr the space can support with 
the actual amount of BTU/Hr used.
 
__________  BTU/Hr (maximum the space can support)
 
__________  BTU/Hr (actual amount of BTU/Hr used)
 
Example:  100,000 BTU/Hr (max. the space can support)    
 
89,000 BTU/Hr (actual amount of BTU/Hr used)
The space in the above example is an  unconfined space 
because the actual BTU/Hr used is less than the maximum 
BTU/Hr the space can support.  If the space had been confined, 
your options would be as follows:
A.  Rework worksheet, adding the space of an adjoining 
room.  If the extra space provides an unconfined space, 
remove door to adjoining room or add ventilation grills 
between rooms.  See Ventilation Air From Inside Build-
ing.
B.  Install a lower BTU/Hr heater, if lower BTU/Hr size 
makes room unconfined.
Converting Confined Space to Unconfined 
Space
Additional volume to convert a confined to an unconfined space 
could come from an adjoining space.  When using an adjoining 
space, you can provide two permanent openings:  one within 
12” of the ceiling and one within 12” of the floor on the wall 
connecting the two spaces (see options 1 and 3, Figure 2),  or 
remove the door into the adjoining room.
Ventilation Air From Outdoors for Unusually 
Tight Construction
WARNING:  If the area in which the heater may be oper-
ated is smaller than that defined as an unconfined space 
or if the building is of unusually tight construction, provide 
adequate combustion and ventilation air by one of the 
methods described in the National Fuel Gas Code, ANSI 
Z223.1/NFPA 54, Section 5.3 or applicable local codes.
Unusually tight construction
 is defined as construction 
where:
a.  walls and ceilings exposed to the outside atmosphere have 
a continuous water vapor retarder with a rating of one perm 
(6 X 10.
11
 kg per pa-sec-m
2
) or less 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 additional fresh air.
You may provide two permanent openings:  one within 12” of 
the ceiling and one within 12” of the floor.  Connect these items 
directly to the outdoors or spaces open to the outdoors.  These 
spaces include attics and crawl spaces.  Follow the National 
Fuel Gas Code NFPA 54/ANSI Z223.1, Section 5.3, Air for 
Combustion and Ventilation for required size of ventilation grills 
or ducts.
IMPORTANT:  Do not provide openings for inlet or outlet air into 
attic if attic has a thermostat-controlled power vent.  Heated air 
entering the attic will activate the power vent.