Kitchen exhaust hood make up air

[djob]

We are in the process of constructing a home using ICF (insulated concrete forms). The kitchen will have a Wolf 1200 CFM exhaust hood. The General Contractor and the HVAC installer both agree that fresh makeup air is required but have not come up with a method to deliver it into the house as conditioned air. We are in coastal North Carolina which can be quite humid. Reviewing several links on the web suggest that no good solution exists:
This link has several other links to related articles.
http://www.greenbuildingadvisor.com/...ir-range-hoods

This information while for commercial ventilation is applicable from the science side.
http://www.energy.ca.gov/reports/200...00-03-034F.PDF

Broan damper for introducing air.
http://www.broan.com/Catalogs/99044565A.pdf

Fan Cycler
http://www.fancycler.com/need/default.htm

If anyone has a workable solution or system available for this we will forward the information to the General Contractor and HVAC installer.

Regards,

djob

[Shophound]

1,200 CFM is equivalent to 3 tons of air conditioning. I do not mean to sound rude, but can someone please explain to me why ANY residential kitchen, outside of a mansion kitchen with several paid chefs cooking for eight hours straight (ala Downton Abbey), needs a high CFM range hood?

My advise is to rethink your desire to have a range hood with this much drawing power. Too often the appeal of the hood blinds everyone to any proper engineering that should go with it. Whoever wants to sell you this hood should also have resources for engineering make-up air requirements. Either that or the architect/builder should be working with a mechanical engineer for this.

[second opinion]

1,200 CFM is equivalent to 3 tons of air conditioning. I do not mean to sound rude, but can someone please explain to me why ANY residential kitchen, outside of a mansion kitchen with several paid chefs cooking for eight hours straight (ala Downton Abbey), needs a high CFM range hood?

My advise is to rethink your desire to have a range hood with this much drawing power. Too often the appeal of the hood blinds everyone to any proper engineering that should go with it. Whoever wants to sell you this hood should also have resources for engineering make-up air requirements. Either that or the architect/builder should be working with a mechanical engineer for this.

I agree shophound, isn't it amassing the lack of knowledge base that is not required to be a contractor. This is an overkill for most residential applications, but some individuals have more money than brains.

[dan sw fl]

For those with more money than brains and elect to have a COMMERCIAL Kitchen Ventilation System (CKVS) installed in a residence,
ADHERE TO THE GUIDELINES FOR CKVS

PAGES 98 - 111
http://captiveaire.com/CatalogConten...atalog_Web.pdf

WHEN DONE, see if you can emulate a tornado.
________________ ________________

At least an attempt can be made to create the same negative pressure.

[motoguy128]

I think it's popular now ot install actualy electric or gas grills indoors. I think it's insane and far too harzardous without a commerical all tile and SS surface kitchen with a fire supression system.

They should include a commercai clean agent system with those fume hoods. All of the sudden they cost as much as a midsized car and prople will stop putting them in.

You can get a 3 ton commerical heat pump rooftop unit with an economizer for a somewhat reasonable price. Spec a 2 position powered damper for the economizer and use supply air temp control. Sure it's overkill.

There's also a company called Floaire tha makes custom make-up air units. We've bought one and I thought they were built fairly well. They reminded me of Comfrot Aire equipment. You nca spec them as packaged units wiht gas fired heat, electric heat, heat pumps or AC condensers integrated. You cna eve get VFD optoins, barimetric pressure control, etc. single or 3 phase power and I think 400-12,000 CFM size ranges. I think a 10" blower is their smallest unit. Probably a 1/2 HP motor for 1200CFM. I think hte price will be clsoe to what hte commerical PKG unit costs.

[dan sw fl]

For those with more money than brains and elect to have a COMMERCIAL Kitchen Ventilation System (CKVS) installed in a residence,
ADHERE TO THE GUIDELINES FOR CKVS

PAGES 98 - 111
http://captiveaire.com/CatalogConten...atalog_Web.pdf

WHEN DONE, see if you can emulate a tornado.
________________ ________________

At least an attempt can be made to create the same negative pressure.

The general principle with a commercial exhaust fan application is to use ~80% of the needed MakeUp Air as Untreated Outside Air.

[motoguy128]

That's the same company as Floaire. I'm not sure who the parent company is. They go under 3 or 4 trade names it seems. They have mfg locations in several places. One is in Central Iowa I believe.

80% is a lot of untreated air to blow into a space.... but now I see what you were talking about. That's a good idea. Supply fresh air directly in front of the exhaust unit, so most of the air being exhausted will be unconditioned. Not ideal for the person working the grill. I'm sure they would like conditioned air blowing on them in summer at least.

[second opinion]

That's the same company as Floaire. I'm not sure who the parent company is. They go under 3 or 4 trade names it seems. They have mfg locations in several places. One is in Central Iowa I believe.

80% is a lot of untreated air to blow into a space.... but now I see what you were talking about. That's a good idea. Supply fresh air directly in front of the exhaust unit, so most of the air being exhausted will be unconditioned. Not ideal for the person working the grill. I'm sure they would like conditioned air blowing on them in summer at least.

Make up air required to be tempered within 10 degrees of indoor air. IMC 508.1.1

[dan sw fl]

That's the same company as Floaire. I'm not sure who the parent company is.

I believe FloAire and CaptiveAir are ENTIRELY Independent.

[motoguy128]

I guess at some point, form follows function. You right, different headquarters on opposite sides of the country. They units and product offering look virtually identical. Especailly the make-up air packaged units. I like that you can specify the units online... if you know exactly what you need.

[dan sw fl]

Make up air required to be tempered within 10 degrees of indoor air. IMC 508.1.1

Makeup Air

IMC 403.1 & 508.1.1 / COMM 64.0309(1),
The temperature differential between makeup air & the air in the conditioned space shall not exceed 10 deg. F

Exceptions:

Makeup air that is part of the air conditioning system

Make air that does not decrease the comfort conditions of the occupied space

[teddy bear]

We are in the process of constructing a home using ICF (insulated concrete forms). The kitchen will have a Wolf 1200 CFM exhaust hood. The General Contractor and the HVAC installer both agree that fresh makeup air is required but have not come up with a method to deliver it into the house as conditioned air. We are in coastal North Carolina which can be quite humid. Reviewing several links on the web suggest that no good solution exists:
This link has several other links to related articles.
http://www.greenbuildingadvisor.com/...ir-range-hoods

This information while for commercial ventilation is applicable from the science side.
http://www.energy.ca.gov/reports/200...00-03-034F.PDF

Broan damper for introducing air.
http://www.broan.com/Catalogs/99044565A.pdf

Fan Cycler
http://www.fancycler.com/need/default.htm

If anyone has a workable solution or system available for this we will forward the information to the General Contractor and HVAC installer.

Regards,

djob

Is there any make-up fresh air ventilation for the home? Considering air tight construction, should have 100+ cfm of fresh make-up air for minimal fresh air ventilation. I have seen a 12" makeup air duct connected to the cold air return of the air handler and routed to the outside. Include a 12" damper activated by the range control. Also restrict the range to 600 cfm. Most do not deliver the rate flow.
Home like this should a whole house ventilating dehumidifier with a fresh air change in 4-5 hours as standard equipment to purge indoor pollutants and renew oxygen. Also during many conditions, the a/c will be unable to maintain <50%RH during any of these types of activities.
Regards TB

[motoguy128]

Make air that does not decrease the comfort conditions of the occupied space

Seems like this would apply if the make-up air is being suppled directly at the point where the exhaust is occuring and that the exhaust is for the purpose of removing heat and fumes to improve IAQ. It seems to me that you've met the intent of the rule. Especailly since it's intended for intermittent use and a specific application. The impact on the occupied space with this design it seems to me would be minimal.

[dan sw fl]

Seems like this would apply if the make-up air is being suppled directly at the point where the exhaust is occuring and that the exhaust is for the purpose of removing heat and fumes to improve IAQ. It seems to me that you've met the intent of the rule.

Especially since it's intended for intermittent use and a specific application. The impact on the occupied space with this design it seems to me would be minimal.

Operating time : 20 minutes 100 times a year.