View Full Version : Things to do before a new unit?
03-30-2012, 02:54 PM
Can someone give me a list, IE load analysis, external static pressure test, etc.. that I need to have done before I go to the next step and hire an installer to put in a new unit. Is there a guide on this site for answers? I have read a ton of posts in the last several weeks, but I want to do it the right way since we will be here for another 10-20 years.
03-30-2012, 04:00 PM
If you don't know the insulation R-levels & air infiltration rate of your home:
I'd always begin with a Home Energy Audit that shows all the options for lowering the heat-gain & heat-loss, then after reducing air infiltration, etc., have a room by room manual J heatload calc performed. A reduction in equipment sizing will usually greatly improve the duct system performance.
This is where the greatest savings in both heating & cooling will accrue; this will help in the down-sizing of equipment.
Also I'd ask for a digital programmable room T stat that also has a cycles per hour (CPH) or a swing setting from 1 to 9 so you can reduce the number of short cycles while increasing the runtime of each cycle. This can really increase SEER performance & help a lot to control humidity problems in the summer cooling mode.
Make sure there is plenty of Return air filter area for the CFM that has to be delivered. thus will help keep the static pressure within an optimal range, like 0.5" WC.
If you have a two story home I want a zoned air flow system so you could control the temps on each floor.
It is also very helpful if you tell us where you live climate-wise; what state & major city do you live near? What is the square footage of your home?
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