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ACCA approved software

Sifu

SAWHORSE
Joined
Sep 3, 2011
Messages
2,773
I have a manual J submittal generated by a software program that is not on the list of approved software by ACCA. ACCA.org states that if the software isn't on the list it is not designed to their standard. Would you accept the submittal as an ACCA load calc?

https://www.acca.org/standards/approved-software
 
Nope. no way. Manual J is the code...

Wow, I have no words for this "energy expert." Take your blinders off?

Virginia added "or other approved heating and cooling calculation methodology" to M1401.3, but, Sifu, you can get there through alternate methods and materials in your admin section. ACCA does not have a monopoly on this, and proprietary ownership of ICC related requirements is frowned upon in the ICC code development community. Would you really not consider accepting a calculation methodology from ASHRAE or DOE or even an individual with a PhD in energy technology? ACCA is not the only entity out there with the knowledge and experience to do a heating and cooling calculation and size equipment appropriately.
 
Wow, I have no words for this "energy expert." Take your blinders off?
.

(Very toung in cheek) May be someone is sipping the cool aid ?

But for blinders, Have you sat with the Author of Manual J8th ? have you seen the math behind what goes into it ?
have you been trained by the author of Manual J ? I have.

What I know about the entirety of code is in my opinion basic at best. I am a certified NYS CEO, that said
am daily humbled by my colleagues knowledge and aspire to one day be as well rounded...

That said and with all due respect, Manual J is so much more than the results of what you see.
Years and years and years of testing have gone into it. Is it perfect ? No. Does it tend to oversize? Yes But, even the author of it
says show me a better method that takes into account as many possibilities for any home on this planet. Its had years of refinement. Been part of (for and against)
probably hundreds (if not thousands) of legal actions.
It has withstood them and the test of time and Its is the defacto standard and mentioned in code for good reason.

Sure, anyone can write software that can provide heat loss calculations. That's easy.
Heat gain on the other hand is what separates the boys from men. No it seperated toddlers from men (and women).
Figure out how to calculate the suns angle of incidence, at the important times of the year, and day, and time while your at it, factor shading and screens, and so on...
likely why imposters oversize wayyy more.... Show me software that does AED or adequate exposure diversity, like any ACCA approved software...

You might ask why is this AED so important, and it is because its a simple way to see if there are any zones or even rooms that present
a challenge to a properly sized system. Having AED is good. Not having it is bad and could lead to serious issues with comfort..

Anyone trained to use ACCA Man J software, who will follow the Do's and Do Not's, will provide whats known as a rigorous Manual J.
They will come up with horse shoes and hand grenades close to what works 110% of the time. ACCA will back you up, IF you have done your part....

If there are other programs that work, all they have to do is submit for testing to ACCA. Sure, the cost to be listed is steep, BUT anyone on this planet can use
Manual J, so the financial possibilities are well worth the investment.

I have seen probably 5-10 "knock off" programs, and the results they provide are completely different than what a rigorous ACCA manual j provides.

On the other hand, and only for block load comparison Rem-Rate (only in new homes) is my bench mark. For cooling loads, it produces the LOWEST required
BTU's of any software. Elite Soft RHVAC is 99.9% as close if done correctly.
I will say out of 500 homes modeled in Rem-Rate, the follow up loads in Elite Soft usually comes to within 95% the first.
When I don't get loads that match between the two (happened may be 3 times in 10+ years) is when I worry about what I have entered.
Im talking about 5-6,000 Sq ft homes where one load may say 39,000 BTU's of cooling and the other may say 39,200 BTUS close...

Any software that tries to simplify the method does at the cost of accuracy.
For cooling, the problem, which is substantial, is comfort is almost always exclusively defined at a temperature instead of temperature AND RH...
Once anyone realizes that RH is at least 50% of the comfort equation, and how sizing greatly affects that part, they quickly realize the smallest equipment that can do the job is always the best. For heating Mean radiant temperature is the other 50%. Understand a heating system that is nearly always producing during the worst times allows everything around you to warm up first, and taking that time allows you (mostly water) to get enough to be comfortable...

If your sport is darts, you want to hit what you aim for. If your into archery, you want to hit that bulls eye. If your into pool, you want that pocket. In almost everything we do we almost always want accuracy.

The most accurate loads should always report the lowest output required to do the job.
Determining the job accurately IS the key.
While Rem-Rate is not designed to produce room by room loads, test for AED and so on, it is a bulls eye for block loads.
Elite Soft done correctly is a bulls eye every day of the week, and twice on sunday.

Code does say Manual J, Ashrae or other APPROVED by the CEO...
I have yet to see one ASHRAE load, and expect that when I do it will be by some MIT grad who is having is own home built.

Full disclosure, I am a trainer of one of the more popular Manual J software platforms. Have trained HVAC and utility professionals form coast to coast.
The blinders have been off for 14+ years and I am proud to say I am cool aid free :)

Other than that, I would never be the CEO to approve any other software unless its demonstrated to ACCA it can work...
 
"Anyone trained to use ACCA Man J software, who will follow the Do's and Do Not's, will provide whats known as a rigorous Manual J."

What about the ones who aren't trained or don't follow the do's and don'ts? The problem I have is that these reports are very dependent upon the integrity of the preparer. I see reports that are all over the place. I have been schooled by multiple "experts" who all say different things. I have list's of "top ten" items for review that are all different. I have multiple houses, very similar to each other (masters and tracts) with reports so different I can't even compare them to try and see why they are different. I feel like the best I can do is check for a few key points like construction assemblies and correct design criteria and move on. I really feel like the code gave us a tool but no way to use it. I think these reports are too easy to manipulate to get an intended result, and I think it happens a lot. Most of the time I can't tell if they followed the do's and don'ts, and if I suspect they haven't I have a hard time defining why.

Code says 68°, 3' AFF, 2' from the wall. That is the performance code we have, other than that I feel like I am left to approve the submission of a load calc, but not approval of the information in it. Thats why I want to see a program that is approved by ACCA.
 
What about the ones who aren't trained

Bingo. You hit the nail on the head. And the info input can and does vary greatly. I know for a fact that the so called experts (not unlike the ones you mention) are experts at gaming the input, to intentionally affect the results.... And yes, what too look for can be like deciphering a new language. I made a recommendation to ACCA to develop a new Manual (Call it Q) Manual Q would be a one page print out of Big ticket items typically used to game the results. Give the code officials a chance. Hank must have had a runin with a few of you fine folks, and wasnt shy about telling me how he felt. After I mentioned CEO, the conversation did no go well... Had a follow up with some one else, and they were interested in hearing more..
Unfortunately, I dropped the ball and never followed up with the task at hand.

But, things that affect cooling loads, Glass SHGC. is #1, number of people in house (should almost always be bedrooms+1) and not in every room at once! The rooms that should have people in them are the rooms that you might expect people to be in during the hottest hours (Here it between 4 and 6PM) Indoor and outdoor design. Duct leakage, duct location. But what bugs me, is folks add 10,000 BTU's under additional loads..
Than they only supply the reports that hide what they have done. Dont get me wrong, if the house has special circumstances, like a rack of servers (IT Professional) than those loads must be taken into account.

I also see that no one pays attention to Manual S.. AHRI conditions are @ 95 Degrees and one air flow. So a 2 Ton system can act larger when the design in real life is 85. A 2 ton system can act even larger with different air flows. The manual J specifies what the air flows should be, and whats required by the home. Manual S say's, if you use this equipment than it will be an imperfect fit, and perfect if its 90-115% of the load... In real life (Especially for the smaller homes) its not uncommon to see 175% or more.. When the argument is given that its the smallest output available in the manufacturers line, We kind of have to walk away.. But when the house is calling for 1.3 tons and they have 2 tons up and 2 tons down, Id fail it every day and twice on sunday. Lastly how many of us actually request the AHRI cert showing model numbers and output to verify what was designed was installed ?

Tons of loop holes. So many, its unrealistic to expect any one of us to check everything. Thats the purpose for 3rd party verification and time has shown they are as much as a problem as every one else....

My lesson to my son, its not lifes challenges that dictate what kind of man you will be but what defines you is how you manage to overcome them... The task at hand is daunting and seemingly insurmountable. All I can do is pick away piece by piece....
 
But for blinders, Have you sat with the Author of Manual J8th ? have you seen the math behind what goes into it ?
have you been trained by the author of Manual J ? I have.

If this is how you wish to set your standards, then I will answer. Yes, I took Hank's class years ago, including taking the test and retaining all the materials. I believe it was a week long class back then (at least). I am not ignorant of Manual J at all (or for that matter,any of the other Manuals). Have some cool aid with me :)
 
Thats why I want to see a program that is approved by ACCA.

In my jurisdiction, we placed this responsibility onto the contractor by requiring they sign a certification form that contains the following:

I hereby certify as the system designer that the above information is accurate and in conformance with ACCA's Manual J, Manual S, Manual D, the ASHRAE Handbook of Fundamentals or other approved methods. I understand that additional information may be requested by the county to determine code compliance.

Enrgxprt's dissertation explained very well the complexities of a load calculation. As a code official, I do not have the time or the resources to review every one of these calculations for accuracy (nor would I want to). That is why we placed that burden on the contractor, where it belongs. Sifu, are you simply accepting load calcs and filing them away, or are you reviewing them? How do you know if what you are receiving hasn't been manipulated, even if it is a program approved by ACCA? Those programs are not infallible.
 
In my jurisdiction, we placed this responsibility onto the contractor by requiring they sign a certification form that contains the following:

I hereby certify as the system designer that the above information is accurate and in conformance with ACCA's Manual J, Manual S, Manual D, the ASHRAE Handbook of Fundamentals or other approved methods. I understand that additional information may be requested by the county to determine code compliance.

Enrgxprt's dissertation explained very well the complexities of a load calculation. As a code official, I do not have the time or the resources to review every one of these calculations for accuracy (nor would I want to). That is why we placed that burden on the contractor, where it belongs. Sifu, are you simply accepting load calcs and filing them away, or are you reviewing them? How do you know if what you are receiving hasn't been manipulated, even if it is a program approved by ACCA? Those programs are not infallible.

Yes, I do review them, that’s kind of the theme of this thread. The problem is how to review them. I like the idea of a certification form but isn’t the report already implying that? Would an additional certification make a difference? If they are fudging the report why would a signed letter make a difference? The fact is I think most of the reports I get have been manipulated and each time I question one I get a new explanation for why it is right from a new “expert” in direct opposition to the last one I questioned. I recently asked an “expert” why nobody submits an S compliance report. I said “it’s the only piece of paper that actually says what it is”. They said everybody should be submitting it, they said it’s the most important piece of the puzzle. The next expert I asked, kind of gave me a blank stare, and said they have never seen one, but not to worry because the same information is buried in the load calc. Who do I go with? Which one should I have teach me what’s wrong with the S?
 
Yes, I do review them, that’s kind of the theme of this thread. The problem is how to review them.

You cannot do an accurate review of a heat loss/gain calculation (report) without having the architectural plans laid out in front of you (not unless you are simply doing a "received report" rather than a "reviewed report" - with a "received report" you will simply have to accept what is provided, without question). To verify a report's accuracy, you will need to review the following.

Every element of the building envelope has a different value attached to it for heat loss/gain. All of these elements come together to form an assembly (stud size and spacing, gyp board, paneling, insulation, tyvec or other house wrap, siding, brick veneer, and how well will the laborer with the caulk gun seal the envelope?). The assembly can be different from one section of the building envelope to the next. There could be one assembly or five different assemblies on the north side of the dwelling alone. You need to know the thermal values associated with all the different types and sizes of windows installed; don't forget the doors. You will need to take into account any shading created indoors and out (oak trees, venetian blinds, draperies, etc.). You will need to have the approved site plan to verify the dwellings orientation. You will need to know how to proficiently apply Manual J concepts in order to verify the report's accuracy. If you were able to conduct that review in the first four hours of your day, it would be time to move on to Manual D and S. Sizing of the equipment relies heavily on an accurate Manual J calculation and the accurate application of Manual D. I say "accurate" in the sense that although the duct system is designed to Manual D specs, the actual installation most likely will not reflect the design, which in turn, will reflect poorly on the results from Manual J and Manual S. Manual D provides different values for ducts that connect to the side of a trunk line as opposed to the top or bottom. It provides different values for short sweep ducts and long sweep ducts, square, rectangle and round ducts. It provides different values to different register transitions. Sooo many different factors likely to change in the field. Unfortunately, you will not be aware of this until you inspect the finished duct system, long after you have approved this design and issued the permit.

How else are you going to verify that the numbers provided to you through that program, ACCA approved or not, are accurate and have not been manipulated in some way.

As you can see, there are so many variables associated with a dwelling unit's HVAC system design that it is best to leave this responsibility to the contractor. If you, as the code official, start rejecting the contractor for things you believe are not aligning to one of these Manuals, you may have just declared ownership of the design. I've seen that happen here, before we changed our process. A homeowner calls the contractor and says that their A/C is running constantly and cannot get the indoor temperature to drop below 79 degrees. The contractor then apologizes and states that they had originally intended to install a 4 ton unit. He then indicated that the building official said that his unit choice was oversized according to Manual S, and that a 3 ton must be installed. You didn't want to be the one in the office to take that call, and there were more than just one of these due to the overzealous reviews of these Manuals.

Now, we place this design responsibility on the contractor alone. If a complaint arises, we happily provide the owner with the signed certification form stating that the contractor designed and installed the HVAC system in accordance with acceptable practices. The owner can take it from there, or they can contact our post occupancy compliance office to receive their assistance in going after the contractor for corrections.
 
Depending on the software used, various reports will show components used in the model. I cant remember the exact name of the report in elite, and will respond here later, but it has all of the component with values that can easily be compaired to Res-Check... As far as manual S goes, some hvac manufacturers make it nearly impossible to locate the interpolation tables. Goodman, Amana are easily had. Others require the person who is doing the manual j to supply the distributor with the design parameters and they in turn supply the data back... its never easy BUT possible (unless its minisplits!)

The key things to look for again are, shgc, indoor and outdoor design, construction (should always be tight for 5ach 50 or less) people, r and u values, equipment loads is where people bury an additional ton..

This is pretty much shovelling sewage against the tide kind of stuff..

Possible solutions but also difficult to implement; require the electronic software files,
require anyone who submits, to first demonstrate knowledge by providing a load calculation on a simple home whos loads are already known, and meets within the known percentage.. Make them pass a test...
require a licensed or registered design professional to sign off,
Create an approved list of individuals
Require proof of training,
And best for last, require a license in that town which incorporates all of the above..
 
You cannot do an accurate review of a heat loss/gain calculation (report) without having the architectural plans laid out in front of you (not unless you are simply doing a "received report" rather than a "reviewed report" - with a "received report" you will simply have to accept what is provided, without question). To verify a report's accuracy, you will need to review the following.
So do you do a received report but with a signed affidavit? I like it, I might push it up the line. I check design criteria and the R/U values against the actual construction. The rest I can let them certify.
 
So do you do a received report but with a signed affidavit? I like it, I might push it up the line. I check design criteria and the R/U values against the actual construction. The rest I can let them certify.

Yes, we accept the certification form, make sure that everything is filled out, then stamp it "received" prior to issuing a permit. We do not review the form for anything other than everything has been filled out. We do not ask that the heat l/g calculation accompany the certification form. The form contains project information, heating and cooling equipment information, a space to draw in a duct layout diagram (doesn't have to be fancy, just complete with sizes of ducts and registers and the room names where the registers are located), and at the bottom is the contractor information and signature. The form has to be onsite for inspections staff to verify the equipment installed matches that on the form as does the duct system. As mentioned before, load calcs and equipment sizing responsibility is left in the hands of the contractor/designer. Contractors and design professionals are also required by our laws to comply with the construction codes in which they engage. Ultimately, unless we as code officials do something to change a design, these people are the responsible parties in their design.
 
One more thing ….. the form contains information for only one zone, or more specific, one HVAC unit. If there are multiple units, there will be multiple certification forms.
 
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