Make Up Air - Page 2 - HVAC - Contractor Talk

Make Up Air

 
Thread Tools Search this Thread Display Modes
Old 03-15-2013, 08:37 AM   #21
Contractor of the Month
 
Inner10's Avatar
 
Trade: Control Systems
Join Date: Mar 2009
Location: Ottawa, ON
Posts: 25,771
Rewards Points: 4,264

Re: Make Up Air


Quote:
Originally Posted by Hardly Working View Post
Wow this is becoming a pretty good thread.

I called my HVAC guy today (that's an Eng.) and after spewing all kinds of math calcs. at me he said wait till they get the heating bill. You not only need make up air but heated make up air. If it's in the 30's it wont take long to cool that house down in just a few minutes. We're talking an extra 45K of BTU in addition to what the house already has.

This can also become an issue when it comes to reselling the house. Is the new homeowner really going to want to spend an extra $30 to cook dinner when they turn the hood on? If it's drawing that much air it's more than likely to suck up grease vapor and collect in the hood. Now let's think safety and fire suppression. He said you could be talking between $4-$12 per CFM. Tell the HO to stop shopping at the discount restaurant supply. 500 CFM should be fine he said.

With that said I no nothing about HVAC. That's why I call him! Basically you've got a big can of worms there. Best of luck and let us know how it turns out.
Aren't even the crappiest of HRV's over 60% efficient?
__________________
The Following User Says Thank You to Inner10 For This Useful Post: Leo G
Inner10 is offline  

Warning: The topics covered on this site include activities in which there exists the potential for serious injury or death. ContractorTalk.com DOES NOT guarantee the accuracy or completeness of any information contained on this site. Always use proper safety precaution and reference reliable outside sources before attempting any construction or remodeling task!

   

Advertisement

 

Old 03-15-2013, 09:24 AM   #22
Pro
 
flashheatingand's Avatar
 
Trade: H.v.a.c.
Join Date: May 2008
Location: Boise, Id
Posts: 3,915
Rewards Points: 3,522

Re: Make Up Air


If the range isn't a commercial one, why not simply open a nearby window (with fan energized) when cooking with oil? K.i.s.s.
__________________
http://www.37flash.com/
flashheatingand is offline  
The Following User Says Thank You to flashheatingand For This Useful Post:
griz (03-15-2013)
Old 03-15-2013, 11:04 AM   #23
Thom
 
thom's Avatar
 
Trade: General Contractor/Homebuilder
Join Date: Nov 2006
Location: Albuquerque NM
Posts: 4,137
Rewards Points: 4,748

Re: Make Up Air


Quote:
Originally Posted by Hardly Working View Post
I called my HVAC guy today (that's an Eng.) and after spewing all kinds of math calcs. at me he said wait till they get the heating bill.
It all depends on the location of the make up air. The closer the air source is to the vent hood the less heat/cooling will be needed. This is one reason many commercial units have the make up air supplied as part of the exhaust hood.

My recommendation for putting the make-up air at the range, possible on the wall behind the range is for just that reason. If you are exhausting unconditioned air that is supplied at the range you won't need much if any additional conditioning.
__________________
Patriotism is being loyal to your country all the time and your government when it deserves it. Mark Twain
thom is offline  
Sponsored Links
Advertisement
 
Old 03-15-2013, 12:49 PM   #24
Contractor of the Month
 
Inner10's Avatar
 
Trade: Control Systems
Join Date: Mar 2009
Location: Ottawa, ON
Posts: 25,771
Rewards Points: 4,264

Re: Make Up Air


wrong thread....ignore
__________________
The Following User Says Thank You to Inner10 For This Useful Post: Leo G
Inner10 is offline  
Old 03-15-2013, 04:25 PM   #25
Pro
 
beenthere's Avatar
 
Trade: HVAC
Join Date: Mar 2009
Posts: 2,440
Rewards Points: 1,186

Re: Make Up Air


Quote:
Originally Posted by Inner10 View Post
Aren't even the crappiest of HRV's over 60% efficient?
HRVs exchange air. They remove X amount of air, and they bring in almost the same amount of air. So it wouldn't be enough to use as make up air.
beenthere is offline  
Old 03-15-2013, 05:49 PM   #26
Carbon Dioxide Producer
 
DuMass's Avatar
 
Trade: EC
Join Date: Feb 2008
Location: MA
Posts: 782
Rewards Points: 500

Re: Make Up Air


They make these MUA systems in up to 10" for resi. It looks like they were specifically designed for when high volume kitchen vent hoods are installed. Can't say I've ever installed one of these myself though.

http://www.ccbinnovations.com/the-product
DuMass is offline  
Old 03-16-2013, 09:19 AM   #27
Thom
 
thom's Avatar
 
Trade: General Contractor/Homebuilder
Join Date: Nov 2006
Location: Albuquerque NM
Posts: 4,137
Rewards Points: 4,748

Re: Make Up Air


Quote:
Originally Posted by DuMass View Post
They make these MUA systems in up to 10" for resi. It looks like they were specifically designed for when high volume kitchen vent hoods are installed. Can't say I've ever installed one of these myself though.

http://www.ccbinnovations.com/the-product
Looks like someone is selling that power activated damper I was talking about. Of course that still does not solve the location thing but it does allow for make-up air when the range hood is on.
__________________
Patriotism is being loyal to your country all the time and your government when it deserves it. Mark Twain
thom is offline  
Old 03-16-2013, 09:33 AM   #28
Pro
 
beenthere's Avatar
 
Trade: HVAC
Join Date: Mar 2009
Posts: 2,440
Rewards Points: 1,186

Re: Make Up Air


Quote:
Originally Posted by thom View Post
Looks like someone is selling that power activated damper I was talking about. Of course that still does not solve the location thing but it does allow for make-up air when the range hood is on.
And if the OP's draft hood would actually remove 900 CFM, he would need 2 of the 10" ones. Plus he would need to increase the furnace size by rough 60,000 BTUs, and a 30,000 BTU increase for the A/C.
beenthere is offline  
Old 03-16-2013, 11:16 AM   #29
Carbon Dioxide Producer
 
DuMass's Avatar
 
Trade: EC
Join Date: Feb 2008
Location: MA
Posts: 782
Rewards Points: 500

Re: Make Up Air


Quote:
Originally Posted by beenthere View Post
And if the OP's draft hood would actually remove 900 CFM, he would need 2 of the 10" ones. Plus he would need to increase the furnace size by rough 60,000 BTUs, and a 30,000 BTU increase for the A/C.
On that end of things, I wonder if they may be able to use duct heaters or get approval to use something like one of the commercial all-in-one units with a duct heater/filter/fan for their resi application.
Seems like a lot of expense for a trophy kitchen that probably won't even get used. I believe if they just go with a 400 CFM or less hood then they wouldn't even be required to provide make up air, but I'd have to double check on that to be sure.
DuMass is offline  
Old 03-16-2013, 11:23 AM   #30
Pro
 
beenthere's Avatar
 
Trade: HVAC
Join Date: Mar 2009
Posts: 2,440
Rewards Points: 1,186

Re: Make Up Air


Quote:
Originally Posted by DuMass View Post
On that end of things, I wonder if they may be able to use duct heaters or get approval to use something like one of the commercial all-in-one units with a duct heater/filter/fan for their resi application.
Seems like a lot of expense for a trophy kitchen that probably won't even get used. I believe if they just go with a 400 CFM or less hood then they wouldn't even be required to provide make up air, but I'd have to double check on that to be sure.
Many of those resi hoods rated at 600 plus CFM are ducted that the don't even move 300 CFM.

Those that move close to their rating are seldom used more then a few times when the MA is connected to the central heat/AC system, Since the other rooms can end up getting cold or hot. And the opening to the kitchen becomes a air tunnel no one wants to walk through. And then when they get the heating or cooling bill they either stop using the hood, the MA, or have both derated.
beenthere is offline  
The Following User Says Thank You to beenthere For This Useful Post:
flashheatingand (03-16-2013)
Old 03-16-2013, 02:06 PM   #31
Pro
 
bconley's Avatar
 
Trade: Kitchen and bath design+remodel
Join Date: Mar 2009
Location: Vashon
Posts: 967
Rewards Points: 500

Re: Make Up Air


Quote:
Originally Posted by txgencon View Post
Seems like you're close to the threshhold of commercial kitchen equipment.

It will be interesting to see if anyone can give you any specifics here.

Good luck.
1200cfm range hoods are all too common in high end residential kitchens.
We have tied a a servo air damper to the hood fan switch in a duct from the outside to under or behind the range.
Code here says if you keep it under 600 CFM no make up air is required.
__________________

bconley is offline  
The Following User Says Thank You to bconley For This Useful Post:
thom (03-17-2013)
Old 03-16-2013, 03:28 PM   #32
Pro
 
Hardly Working's Avatar
 
Trade: Carpenter
Join Date: Apr 2005
Location: Seattle,WA
Posts: 1,011
Rewards Points: 812

Re: Make Up Air


Quote:
Originally Posted by beenthere View Post
Many of those resi hoods rated at 600 plus CFM are ducted that the don't even move 300 CFM.

Those that move close to their rating are seldom used more then a few times when the MA is connected to the central heat/AC system, Since the other rooms can end up getting cold or hot. And the opening to the kitchen becomes a air tunnel no one wants to walk through. And then when they get the heating or cooling bill they either stop using the hood, the MA, or have both derated.
While talking with my HVAC Eng. he told me of a time when someone did put an over sized hood in and they thought the dog was digging in the fireplace. Turned out the fan was sucking air down the chimney and sucking the ash into the room.

Homeowners and their grand ideas. They see this chit on TV or someones home with no idea what it take to put it in and when you tell them the cost they think your a thief.
Hardly Working is offline  
Old 03-16-2013, 04:37 PM   #33
Contractor of the Month
 
Inner10's Avatar
 
Trade: Control Systems
Join Date: Mar 2009
Location: Ottawa, ON
Posts: 25,771
Rewards Points: 4,264

Re: Make Up Air


Quote:
Originally Posted by beenthere View Post
HRVs exchange air. They remove X amount of air, and they bring in almost the same amount of air. So it wouldn't be enough to use as make up air.
Any reason why you couldn't run your vent hood through a charcoal filter then into an HRV?

I had a friend try it with a dryer and it lasted about 3 weeks until it was completely clogged with lint.
__________________
The Following User Says Thank You to Inner10 For This Useful Post: Leo G
Inner10 is offline  
Old 03-16-2013, 04:44 PM   #34
Pro
 
beenthere's Avatar
 
Trade: HVAC
Join Date: Mar 2009
Posts: 2,440
Rewards Points: 1,186

Re: Make Up Air


Quote:
Originally Posted by Inner10 View Post
Any reason why you couldn't run your vent hood through a charcoal filter then into an HRV?

I had a friend try it with a dryer and it lasted about 3 weeks until it was completely clogged with lint.
You would have to also add a grease filter to prevent it from clogging. Plus would still need an additional 24,000 to 30,000 BTUs for heating, and 12,000 to 18,000 BTUs of additional cooling.
beenthere is offline  
Old 03-16-2013, 04:48 PM   #35
Contractor of the Month
 
Inner10's Avatar
 
Trade: Control Systems
Join Date: Mar 2009
Location: Ottawa, ON
Posts: 25,771
Rewards Points: 4,264

Re: Make Up Air


Hmmm...what if you ran the exhaust through a filter then back into the house and then exhausted an HRV near by to freshen things up?
__________________
The Following User Says Thank You to Inner10 For This Useful Post: Leo G
Inner10 is offline  
Old 03-16-2013, 05:27 PM   #36
Pro
 
beenthere's Avatar
 
Trade: HVAC
Join Date: Mar 2009
Posts: 2,440
Rewards Points: 1,186

Re: Make Up Air


Quote:
Originally Posted by Inner10 View Post
Hmmm...what if you ran the exhaust through a filter then back into the house and then exhausted an HRV near by to freshen things up?
What if they always go out to eat and never use the exhaust hood. Never need make up air then.

Advertisement

beenthere is offline  


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Why is wood rotting ? SKC Construction 47 05-27-2018 04:50 PM
Hidfast Gun redwood Decks & Fencing 28 06-08-2012 06:43 PM
Need to make DIY Bug Screens, please help finakat Windows, Siding and Doors 8 05-19-2012 07:36 PM
Make Code Books Free 10fingers General Discussion 35 07-18-2009 10:59 AM

Join Now... It's Fast and FREE!

I am a professional contractor
I am a DIY Homeowner
Drywall Talk is for
PROFESSIONAL CONTRACTORS ONLY!

At DrywallTalk.com we cater exlusivly to professional contractors who make their living as a contractor. Knowing that many homeowners and DIYers are looking for a community to call home, we've created www.DIYChatroom.com DIY Chatroom is full of helpful advices and perfect for DIY homeowners.

Redirecing in 10 seconds
No Thanks
terms of service

Already Have an Account?