HVAC instead of Hood

[Francis Vineyard]

2009 IMC 507.2.2 now permits multiple electric appliances without a hood, how will or do you allow this exception with the HVAC design?

507.2.2 Type II hoods. Type II hoods shall be installed

above dishwashers and light-duty appliances that produce

heat or moisture and do not produce grease or smoke, except

where the heat and moisture loads from such appliances are

incorporated into the HVAC system design or into the

design of a separate removal system. Type II hoods shall be

installed above all light-duty appliances that produce products

of combustion and do not produce grease or smoke.

Spaces containing cooking appliances that do not require

Type II hoods shall be ventilated in accordance with Section

403.3. For the purpose of determining the floor area

required to be ventilated, each individual appliance that is

not required to be installed under a Type II hood shall be

considered as occupying not less than 100 square feet (9.3

m2).



Was this topic discussed before?

 

[cda]

in the commentary it seems to say this was past practice in the code, it is just trying to clean up the section a little bit

 

[Francis Vineyard]

cda thanks for the response. Now it sums up the type of appliances instead of continuing the expanding laundry list of exceptions.

As usual my question may be better stated a Type 2 hood has always been installed when there is more than one of the appliances listed in the 2006 section 507.2.2 Exception 3. No one has opted to alter the HVAC system to comply; do you accept the license contractors design or require something more such as calculations or RDP stamp?



Don’t have my ICC available at this time but this is the Virginia 2006 exception;



“A single light-duty electric convection, bread, retherm, steamer or microwave oven designed for countertop installation. The additional heat and moisture loads generated by such appliances shall be accounted for in the design of the HVAC system.”

 

[cda]

I do not have to worry about it for another two months or so.

Still under 03.

Hopefully you will have it solved by than, and I can use your expertise !!!!!!!

 

[alora]

Was this topic discussed before?

Sort of.

http://www.inspectpa.com/forum/showthread.php?3625-Type-II-Hood-With-2-Microwaves

 

[alora]

..., how will or do you allow this exception with the HVAC design?... For the purpose of determining the floor area

required to be ventilated, each individual appliance that is

not required to be installed under a Type II hood shall be

considered as occupying not less than 100 square feet (9.3

m2).

In a "B" occupancy, +1 microwave = +1 person.

The ME will figure out the rest.

 

[Papio Bldg Dept]

As usual my question may be better stated a Type 2 hood has always been installed when there is more than one of the appliances listed in the 2006 section 507.2.2 Exception 3. No one has opted to alter the HVAC system to comply; do you accept the license contractors design or require something more such as calculations or RDP stamp?

We require an RDP stamp for an HVAC design without a hood. I suppose if we had a licensing/registration program for mechanical contractors (or any contractors for that matter) we might consider someone other than RDP, but calculations would have to be submitted with design. In my opinino, it is too big of a risk when adding that much humidty to your ductwork system.

 

[alora]

Don’t have my ICC available at this time but this is the Virginia 2006 exception;

Here it is, 2006 IMC:

3. A single light-duty electric convection, bread, retherm or microwave oven. The additional heat and moisture loads generated by such appliances shall be accounted for in the design of the HVAC system.

 

[Francis Vineyard]

Alora thanks for the link.

Is it correct that according to section 312 the standards reference does not require a RDP for non-residential 3 stories or less to design the HVAC system?

 

[Paul Sweet]

Francis, the Va. Related Laws Package has a table on pg. 70 saying where the HVAC contractor can do this.

http://www.dhcd.virginia.gov/StateBuildingCodesandRegulations/PDFs/2009/Related%20Laws%20Package.pdf

There are tables in HVAC textbooks & guidelines that can help the desinger estimate appliance loads.