We did a fantech unit last year in a kitchen. 5' Range hood blowing about 1200 cfm if I remember correctly. We installed an in line heater in the fan unit. 20 amp run to the make up air system and if I remember right the heater pulled 240v and 40 amps. Our electrician said that when that baby went on in the winter it was like turning on 2 electric dryers. Needless to say it is not easy finding a good spot outside for a 10" air intake, a 16x16 floor grate (they don't recommend splitting the supply air inlet) and room for the duct work. Not to mention the space for the unit itself. Putting all that together is a challenge. When researching solutions, Fantech does note that this thing shouldn't be dumped into the home hvac system.

I will say when the hood goes on without the makeup air ( we turned it off to see if we could feel a draft coming back into the house, it only takes about 20 seconds untill you begin to smell soot coming back down the chimney. But (becasue the range hood controls the make up air) when the hood goes on the make up air blows. With the heater on in the dead of winter it only blows cold for a few seconds.

Best of luck.

 

Usually it's just because they got a ginormous gas stove.

 

LOL, you guys need to stop judging others' desires before somebody accuses you of Marxism 😁
Nobody NEEDS anything, many live in mud huts with barely enough food and no shoes. But you're not going to make money building stuff for them.

 

Do mud huts need make up air by code?

 

Mud huts? No.


Yerts?.....Yes. But only over 350sqft above climate zone 3.

 

That's because Yerts are only 85sf and the air exchange rate is 4x a minute.

 

Maybe, HVAC experts install makeup air systems, which are designed to provide fresh air into a building or space to replace air that is exhausted due to ventilation or other processes. You should hire the expert ones who are specialized in this work.

 

LOL. Most HVAC people are clueless on the subject.

 

If you are building a new home presumably you have approved plans and a permit and will have to do exactly as the plans show. Otherwise you will fail inspection. No?
So what do the plans show?

 

Maybe no plan needed and can be built by code?

 

My company sells special hole cutters for use by the building trades including HVAC contractors and so I have more exposure than most. I concur that it is difficult to find a contractors able to do the calculations for a new system and that is in particular with regard to heat pumps and mini split and high velocity systems. One needs to be more diligent to find the one with the needed expertise.

Contractors in the northeast need to be more savvy than ones in the west and what is commonplace in New England is still considered experimental where I live in California. Nonetheless I have worked with some exceptional HVAC contractors in California and will pay for travel time to get them onsite when needed.