Replywe are looking to add 8 registers total and use all flex ducting... thanks!
New Guest
I am a service and repair based company and looking to do a small new install duct/unit etc... The house is 1k sqft and we are putting a 2.5 ton on the house but i need help with the load calcs and the duct sizing... any help would be greatly appreciated... Thanks!!
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we are looking to add 8 registers total and use all flex ducting... thanks!
Professional Member*
Try Manual J & Manual D
New Guest
?
Professional Member*
That's a lot of tonnage for 1000 square feet. Most of the homes around mine are that size and a 1.5 ton keeps them cool until it gets over 100 outside. These are cheaply built 60 year old homes.
Professional Member*/ARP Committee
What area you in?
I'm at 1300 square feet of 1950's block wall construction, and a crappy roof design.
2.5 ton, and it's oversized, for the cincinnati area.
"Better tell the sandman to stay away, because we're gonna be workin on this one all night."
"Dude, you need more than 2 wires to a condenser to run a 2 stage heatpump."
"Just get it done son."
Dad adjusted
Professional Member*
I always liked Dirty Harry movies and when I read this post....what comes to mind is....From Magnum Force....
"A man has got to know his limitations"
Everyone has to start somewhere and it sounds like a crash course in Manual J,D,T,S is required.
I wish I had a $1.00 for every response I deleted.....
"Decidedly Superior in a twisted pathetic way".....
Professional Member*
only 8 registers ? So you're oversizing the unit , and going to starve it for air as well ... hmm
Professional Member
2.5 tons is way overkill for a place that size.
Professional Member
You're about a ton over what you need unless the house has 20 foot ceilings or is missing an exterior wall
Professional Member
this is the best part of his reply. this says it all!Originally Posted by ChrisHVAC25
Professional Member
How did you decide on the tonnage and number of registers without doing any calculations?
Member
Translation; I am a diyer posing as a hvac tech and I am not doing a very good job of it.
Professional Member*
Got it online.
Professional Member
Here in Phoenix, Arizona. 2-2.5 ton is a very good choice.
Decide what you want, decide what you are willing to exchange for it. Establish your priorities and go to work." H.L. Hunt
"In order that people may be happy in their work, these three things are needed: They must be fit for it. They must not do too much of it. And they must have a sense of success in it." John uskin
Professional Member*
I suppose for a 115F design temp that could make sense
Regular Guest
Hello Christopher,
Manual J is a form that indicates the heat loss/gain load. Manual D is for duct design, Manual S is for equipment and Manual T for those eight beautiful inlaid walnut bordered teak wooden registers custom made with decorative wildlife scroll art. Look, you can't really be effective until the load is justified properly. The form will give you specific heat multipliers for various types of construction envelopes considering infiltration and ex filtration to compensate by means of sensible loads as well as latent. I'm sure you could look up equations on thermal conductivity values of K or transfer rates of U; however, this is why the forms above are used as a healthy start for comforting your customer..
Regular Guest
Just remember the amount of degree days, and the design temperature...
p.s. Hemoglobin in refrigeration lines might be an oxygen transporter but it would take iron. Imagine a surfactant lined purging system that expelled oxygen rather than non condensable pollutants?
Professional Member*/ARP Committee
Drugs are bad, mkay?
"Better tell the sandman to stay away, because we're gonna be workin on this one all night."
"Dude, you need more than 2 wires to a condenser to run a 2 stage heatpump."
"Just get it done son."
Dad adjusted
Professional Member
A service tech that has never heard of manual j or manual d.... hmmmmmm
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