Residential HVAC design
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Does one need an engineering degree (and/or certifications) to perform residential Manual J, S, D, and T calculations as a third party consultant? Merely curious.
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And I’ve read the GBA article about who can design systems. Just curious if consultants have engineering degrees, or if it isn’t necessary.
From what I understand, these calculations are done with software, after feeding in the dimensions and specs of the building. A regular civilian can definitely do that. But these are not consumer-friendly software — so if you're a person who uses mainly email and productivity tools like office, there's going to be a steep learning curve.
Corbett Lundsford did a video a while back showing the interface for some of these ... yikes! https://www.youtube.com/watch?v=62IcpiTHICI
I can't speak to the legal aspect of selling these services without the degrees, if that's what you're asking. Generally speaking, a lot of folks in the trades don't have degrees, or it might be in another field than this specific thing.
No. Engineering degrees teach physics, chemistry, thermodynamics, heat exchange, and hydraulics. This is a good background but not required. I have learned more from technicians than from my professors. Once you understand heat and mass exchange combined with common sense then it is straightforward.
Depends on the licensing requirements of your state.
New construction plans require sign off by a licensed engineer for building permit in my area. I think a manual J fee for service is tough sell because most customers don't understand the value of it and there will be lots of contractors telling customers they don't need it. (personal experience when replacing my system, so I bought a program and did it myself)
No, and as of now, in 15 southern states I've worked, I don't know of any municipality that requires engineering stamp on residential systems.
There are several software available, some are free, you can use to perform all manuals. I perform my own manual Js to make sure HVAC contractors start on the right foot and include the right information, as in garbage in, garbage out. The other manuals are more complicated and time consuming to do it right.
Finding and hiring a reputable HVAC designer and/or contractor is a key. I've used Energy Vangard in several jobs.
I failed out of engineering school but with the free LoopCAD trial I ran a Man J on my in-progress house and came up with 45,000 BTU heat loss. I the blueprints over to Arctic Heat Pumps who ran a free sample for me and it came back 41,000 BTU so I was pretty close. Not bad for my first ever attempt! Really the programs hold your hand to the point where just about anyone could do the Man J. I have not tried the S and the D so I can't comment on that.
That being said there are several website/companies that have nation-wide credentials and licensure and only charge like $500 for a full J/S/D package.