Online Manual J load calculator

[garyed]

After about two years I finally got my online Manual J load calculator finished.
Its been a fun project so far & I hope someone can get some use out of it besides myself. I also plan to add some data for Canada in the near future.
I'd appreciate any ideas or feedback from anyone.
The site is at: http://www.loadcalc.net

[Cooked]

Thanks Gary! May I offer some constructive criticism?

[enb54]

After about two years I finally got my online Manual J load calculator finished.
Its been a fun project so far & I hope someone can get some use out of it besides myself. I also plan to add some data for Canada in the near future.
I'd appreciate any ideas or feedback from anyone.
The site is at: http://www.loadcalc.net

Hi Gary...
I tried to enter my house specs and could not find anything even approaching it... I'd suggest increasing roof R values up to about R70 or so (and above), and at least R50 (and/or above) for walls. Otherwise, looks like you are doing something good, give yourself a raise!

[garyed]

Thanks Gary! May I offer some constructive criticism?

Definitely, I would appreciate hearing it.

[Gunslinger]

drop down menus for constructions are cut off. Using this calculator, one would need to use manual J book to look up construction numbers, right?

nice job, I'm sure you have a lot of time in this project.

[garyed]

Hi Gary...
I tried to enter my house specs and could not find anything even approaching it... I'd suggest increasing roof R values up to about R70 or so (and above), and at least R50 (and/or above) for walls. Otherwise, looks like you are doing something good, give yourself a raise!

Thanks, I'll try to find some higher R-values to add.

[garyed]

drop down menus for constructions are cut off. Using this calculator, one would need to use manual J book to look up construction numbers, right?

nice job, I'm sure you have a lot of time in this project.

Thanks for the input,
No, you shouldn't need to use any manual J book.
Can you tell me what browser & OS versions you're using.
Not all browsers work the same, depending on the OS & version numbers there are sometimes features that can be left out or displayed different.
Sometimes its easily fixable & sometimes not. I've already made some adjustments to accommodate some different browsers but its hard to test every one so I would appreciate your info.

[Gunslinger]

you have mail. I am using windows IE

[Gib's Son]

Nice job. I might try comparing it against Trane Trace or Carrier HAP when I have some spare time.

[garyed]

Nice job. I might try comparing it against Trane Trace or Carrier HAP when I have some spare time.

I'd be curious to see how they compare.
The one thing I know I left some room for error is the duct load. I used a default spider duct system instead of allowing for the actual duct area. The problem with making things simple is it makes things less accurate also.

[catblackmore]

My husband and I are building a house ourselves, contracting out minimally--stuff like the concrete and the HVAC. In order to pull building permits, we have to have a manual J load calculation. In trying to use yours, in the "Floor" options, I discovered there's no choice for a "floor over a basement." Are any of the options you have listed comparable? We're doing a 1550 sq ft house over a full basement, 8 ft below grade/9ft ceilings, which we will finish at some point on down the road. Any help/insight you can provide would be appreciated!

[catblackmore]

After about two years I finally got my online Manual J load calculator finished.
Its been a fun project so far & I hope someone can get some use out of it besides myself. I also plan to add some data for Canada in the near future.
I'd appreciate any ideas or feedback from anyone.
The site is at: http://www.loadcalc.net

My husband and I are building a house ourselves, contracting out minimally--stuff like the concrete and the HVAC. In order to pull building permits, we have to have a manual J load calculation. In trying to use yours, in the "Floor" options, I discovered there's no choice for a floor over a basement. Are any of the options you have listed comparable? We're doing a 1550 sq ft house over a full basement, 8 ft below grade/9ft ceilings, which we will finish at some point on down the road. Any help/insight you can provide would be appreciated!

[garyed]

My husband and I are building a house ourselves, contracting out minimally--stuff like the concrete and the HVAC. In order to pull building permits, we have to have a manual J load calculation. In trying to use yours, in the "Floor" options, I discovered there's no choice for a floor over a basement. Are any of the options you have listed comparable? We're doing a 1550 sq ft house over a full basement, 8 ft below grade/9ft ceilings, which we will finish at some point on down the road. Any help/insight you can provide would be appreciated!

Since I haven't gotten into basements yet on the program the closest thing to unconditioned basement would be "closed or vented crawl space" with whatever insulation you plan to have. I would recommend that you get an HVAC pro to do a loadcalc to be safe that your system is sized correctly. Even using the same program, rarely do two people come up with the same numbers on the same house. It takes a basic understanding
to do a proper loadcalc no matter what program you use & there's never a guarantee that the program itself doesn't have errors.

[jch]

I'd appreciate any ideas or feedback from anyone.
The site is at: http://www.loadcalc.net

What an excellent resource you've built! Thanks for doing that -- it's great. The numbers are quite close to my actual electrical usage during heating season

I hope you continue to work on it!

Cheers,
.../j

[garyed]

Thanks,
I'm considering working on a room by room calculator down the road but it would take a lot more time for the user to do a lodcalc online.

[54regcab]

Now if people would only install equipment based on what the ManJ says. No input fudging either !!

[BenRu]

Great Thanks!

[GT1980]

Thanks,
I'm considering working on a room by room calculator down the road but it would take a lot more time for the user to do a loadcalc online.

GREAT! and I 've done maybe 3000+ studies, as many have over a 30 years HVAC, too.

I adjusted slant-fin's room by room for loop sizing with matching my 34f or more performance guaranteed northern loops. KITEC of CAN had a free one also .

Solstar was the first offering true-er results in 1979-1980 that matched strip heating electric forced air near perfectly, turned out great for loops sized on older homes and comm.

Although design temps I look at the peaks a little differently than J, to stay out of courts with GT Comforts, closed loop.

[chal]

Gary,

Is the format for your Manual J printout (from www.loadcalc.net) essentially the same as the printout from an ACCA approved software? If so, what software has that same printout?

I need to know how the contractor performed his Manual J analyses, based it seems on a 2002 version. The furnace he installed is greatly undersized, as evidenced by 1). the house temperature falling to 63 degrees when the outside temperature fell to -14, despite the furnace running continuously and by 2). use of your site www.loadcalc.net, showing much higher BTU/h required.

Thanks so much.

[garyed]

Gary,

Is the format for your Manual J printout (from www.loadcalc.net) essentially the same as the printout from an ACCA approved software? If so, what software has that same printout?
.....

Not only would my printout would be different, probably no two loadcalcs are going to be the same even with the same software and the same house.
The only way to be sure you're getting a printout the same as an ACCA approved software would give you is to to actually use one of their approved packages. These are the only ones I'm aware of:
1 - Wrightsoft Right-J8
2 - Elite RHVAC
3 - Florida Solar Energy
4 - CarmelSoft HVAC ResLoad-J
5 - Avenir MJ8 Editions