HVAC Load Calculator

Does anybody have a link to a manual heating & cooling load calculator. I want to size a mini-split system for a 20x30 detached garage addition. All I've found on the web are offers to purchase load calculation s/w.

Reply to
Jeff Dieterle
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Excel?

Reply to
George

That's 600 square feet and NOT a standard home. I suggest you do 2 tons (24,000 btu).

But if you like it to get cold fast, then 3 or 4 tons.

If you just want to remove the humidity and cool it to 80 on a 95 degree day, then 1 1/2 ton (18,000 btu) will work just fine.

In other words, forget the calc. Completely useless. The important question is to ask the owner what he wants to accomplish with his AC.

Reply to
ValveJob

?!

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Reply to
RicodJour

So you like to guess....

You don't even know if this building is insulated!!!!!

Reply to
<kjpro

There used to be a more complete free load calculator but I couldn&#39;t find it. Here&#39;s what I found as far as free software goes:

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Reply to
Ermalina

It sounds like we found the new Miss Cleo.

You don&#39;t know where the building is located, what exposure it has, what materials it is made from and the amount of insulation it has and you can develop such an amazing answer...

Reply to
George

Whos ass did he pull those numbers out of??

Better check with the local inspectors and permits department. Most likely they will require a Manual J heat load and loss calculation in addition to the plans for the structure modifications.

Reply to
Noon-Air

You may not like it but is very reasonable answer! Tony

Reply to
Tony

I was thinking the same

Reply to
longshot

Well, if you&#39;re making the same assumptions, sure, it would seem reasonable. Let me ask you a few question to see what assumptions you&#39;ve made. Where is the garage located? What is it&#39;s exposure? What is the construction? What are the design temperatures? What takes place in this garage? Are there additional heat or humidity loads? Is there a 2nd floor?

Comments such as, "In other words, forget the calc. Completely useless. The important question is to ask the owner what he wants to accomplish with his AC." are worse than useless, they&#39;re misleading.

Starting with a wild-assed guess based on all sorts of assumptions isn&#39;t designing a system. Oversizing a system is bad, undersizing a system is bad, and you&#39;re pretty much guaranteed to have one or the other with WAG designs.

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Reply to
RicodJour

Here in my neighborhood, if we see a inspector on our property talking about permits, we kill him. It is not against the law here.

Reply to
ValveJob

When I see a city inspector, I shake his hand and thank him for holding the hacks feet to the fire and helping to raise the quality bar. I then ask him if he is up to par on the new batch of hacks thats coming out of the woodwork. Does he know about XXX job??

No I don&#39;t just drop dimes, I drop dollar bills. If I have to play by the rules, then its only fair that everybody else should be doing the right things right too. That includes pulling permits and having inspections done.

Reply to
Noon-Air

Sorry Ricod;

If you want to play with the big boys, you&#39;re going to have to pony up for the software [like I did / do.]

If you want some &#39;free&#39; answers to load questions, then take some classes.

Otherwise, hire a professional, and have him/her install your system. FWIW: on 600 square feet, if its just one large room, you might consider ductless units to heat & cool your space. Even if it is separated in to two spaces with a partition, you can have two indoor sections with one outdoor section.

Reply to
Zephyr

What a nifong. Learn to read - I&#39;m not the OP.

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Reply to
RicodJour

Reply to
Telstra

Reply to
Telstra

Reply to
Jeff Dieterle

Sorry, Ricod - I mis-spoke, I thought you posted the start of this thread, when I guess you answered the O.P. from where I don&#39;t know [only because it [the original O.P. ]wasn&#39;t listed on my crappy newsreader.]

Reply to
Zephyr

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