HVAC System Sizing

[brat]

I posed this question a long time ago on the ICC BB and didn't get a lot of response. I'll try again here. How many of you require HVAC equipment and ducts to be sized per ACCA Manuals J and D as required by the 2006 IRC M1401.3 and M1601 1(and IECC)? The 2009 code adds ACCA Manual S for equipment selection. We are getting close to starting to seek compliance with these requirements, following suite with other areas of our State. We are trying to make it as easy and user friendly as possible. What exactly do you accept/require for submmittal? What sort of issues have you encountered along the way?

Thanks for your input.

 

[RJJ]

Re: HVAC System Sizing

I remember that post! I suggest ACCA manual J or d and s for equipment. Not using 2009 yet. In the last few years it seems most equal or exceed the requirements. Does not even seem to be an issue.

 

[raider1]

Re: HVAC System Sizing

We require that residential HVAC systems be sized in accordance with ACCA Manual J and the duct be sized in accordance with Manual D.

We will accept any report that uses the Manual J and D methodology. Most of the time we will get a report that was done using Wrightsoft. This is a computer software system that is based on Manual J and D. The reports contain the building elements for each room and will give a detailed analysis of each room for a heating and cooling load.

Typically these reports are about 30 pages long.

Chris

 

[vegas paul]

Re: HVAC System Sizing

I have sort of an "in-between" answer. Yes, I require systems to be sized with ACCA Manuals J & D, however, I do not require a report to accompany the plans. I will check a plan against those manuals, and if they meet/exceed the requirements, I will approve it. More work for me, but better customer service and possibly cheaper for homeowners, if they are not using an ME or Mech. Contractor that would charge extra for the report.

 

[Mule]

Requiring Manual J on Existing Equipment Change Outs

We have started requiring HVAC contractors to submit calculations on older homes when changing out the condensor and inside unit.

The contractors are screaming! Well 3 or 4 of then anyway! They are saying that by requiring this that units will be undersized.

Are any of you guys/gals requiring calculations on change outs?

Should I be requiring the HVAC guys to submit calculations? If I am reading the code correctly I think I am right.

Pros...Cons.... Help me out! I've contacted a lot of the cities in the area and they are not requiring it. I'm starting to second guess myself!