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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 6022
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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Total home square footage is 3200.insulated attic, walls

Customer Question

Total home square footage is 3200.
insulated attic, walls and under floors
3 bedrooms are at end of house closest to split units totaling 650 square feet
Other rooms are:
kitchen, living room and dining area combined 750 square feet
den 530 square feet
game room 700 square feet
I did not plan to AC baths, halls and storage rooms
Total air conditioned rooms is 2630 square feet
I am considering a RA1448AJ1 4 ton 14 SEER straight cool condenser and a
RH1P4821STAN - Rheem 4.0 ton air handler.
Is these units the right size for my home?
What are the tube sizes coming out of the air handler for outgoing air and return air?
What are the CFM's?
The farthest register will be 100 feet from the blower.
What diameter should the ducts be?
What sizes should the registers be for incoming air and return air?
Is this system 2 stage or 1 stage?
Is it variable speed and if so, what are the speeds?
What is the size of the electric cable required?
Thank you for your help.
Submitted: 2 years ago.
Category: HVAC
Expert:  Phil replied 2 years ago.
Hello, welcome to Just Answer!The sizing depend heavily on the local climate and your tolerance for temperature excursions above the set point on the thermostat. Tell me if you would not mind it getting to 78F in the house a few days a year in the late afternoons or not. and which is the nearest town or city so that I can assess the climate conditions. I also need to know if you have double insulated windows or not. Tell me if you are going to install this yourself or have a licensed local HVAC contractor do it for you.. A house that size can be broken into two zones so that you are not heating or cooling zones that are not in use at the time, that can cut your operating costs by 30% or more. If this is going to be a do it your self project you will need a lot more help than can be provided for your offer amount... Once I have that data I will submit an offer for some design services.
Expert:  Phil replied 2 years ago.
Here are a few screen shots from previous projects
shows supply air duct main size and one of many options for zone dampers, a close up, worms eye view.