Manual J, S, D services

[vortech91]

currently have a boiler system in 2100 sq/ft ranch home with basement. Before I finish the basement I wanted to install ductwork and a new furnace and A/C system. Im trying to find a reputable company that can do a manual J, S, and D calculation for me. Can anyone recommend a good company online ?

 

[metlmunchr]

Do you have complete drawings of your house including wall details, window details, insulation values, and all the rest of the information required for load calculations?

Honestly, any contractor who's capable of doing a proper job is also capable of doing the calculations as a part of the job. Unfortunately, the majority of residential HVAC contractors are not capable of doing a proper job.

All the calculations in the world won't make a bit of difference if the system is installed by someone who puts a box on the discharge of the furnace and starts stringing 40 to 50 foot runs of flex. That seems to be the standard procedure for about 3/4 of the ones out there today. And don't make the mistake of hiring someone based on price and then assume they'll do a good job because you've got a sized layout. They don't know where to start, and in short order, when you question the fact that they aren't following your layout, the immediate response will be "This is the way we always do it". Fact is, its the only way they know.

I wouldn't hire any contractor who isn't willing to show me one of his jobs with ductwork installed or in progress. Forget the sales talk and the spiffy sales dude in his izod shirt and khakis. Hot air doesn't equate to satisfactory results, and some of the worst ones out there survive by having the best of quick talking salesmen. The proof is in the actual work, and the best indicator of a good contractor is work performed in a neat and workmanlike manner. Its not hard at all to recognize the difference between that sort of work and the slam it in and run type messes that are way too prevalent.

Bottom line.... A satisfactory heating and cooling system is dependent maybe 10% on design (assuming the designer is competent) and 90% on execution

 

[eddieK]

Do you have complete drawings of your house including wall details, window details, insulation values, and all the rest of the information required for load calculations?

Honestly, any contractor who's capable of doing a proper job is also capable of doing the calculations as a part of the job. Unfortunately, the majority of residential HVAC contractors are not capable of doing a proper job.

All the calculations in the world won't make a bit of difference if the system is installed by someone who puts a box on the discharge of the furnace and starts stringing 40 to 50 foot runs of flex. That seems to be the standard procedure for about 3/4 of the ones out there today. And don't make the mistake of hiring someone based on price and then assume they'll do a good job because you've got a sized layout. They don't know where to start, and in short order, when you question the fact that they aren't following your layout, the immediate response will be "This is the way we always do it". Fact is, its the only way they know.

I wouldn't hire any contractor who isn't willing to show me one of his jobs with ductwork installed or in progress. Forget the sales talk and the spiffy sales dude in his izod shirt and khakis. Hot air doesn't equate to satisfactory results, and some of the worst ones out there survive by having the best of quick talking salesmen. The proof is in the actual work, and the best indicator of a good contractor is work performed in a neat and workmanlike manner. Its not hard at all to recognize the difference between that sort of work and the slam it in and run type messes that are way too prevalent.

Bottom line.... A satisfactory heating and cooling system is dependent maybe 10% on design (assuming the designer is competent) and 90% on execution

Unfortunately - This type of performance comes with a matching price.

40 yrs of experience - I let people know going in, I am NOT going to be the lowest quote and in fact I may be the highest quote.

 

[danski0224]

currently have a boiler system in 2100 sq/ft ranch home with basement. Before I finish the basement I wanted to install ductwork and a new furnace and A/C system. Im trying to find a reputable company that can do a manual J, S, and D calculation for me. Can anyone recommend a good company online ?

Your best bet would be to do a search on your own. There are many hits for an online search.

There are people/companies that only offer Manual J, S and D calculation services only- without offering HVAC installation services.

I would guess that most GJ members would be too cheap to do so, and then would complain here about poor HVAC performance later

 

[mrpizza]

I almost always do a manual J on a house before pricing new equipment. Manual D for new construction. We also change a lot of duct supply fittings from squared off **** to radius. We are not the cheapest game in town.