Is it possible to create a better temperature controlling system

ductshvactemperaturethermostat

I have a two story 2.5k sq ft house with a varying degree of temperature throughout the house. The main problem is that the air coming out of vents are very weak if almost nil. Only the living room that's closest to the unit in the garage has full strong air and the rest of first floor and the whole second floor has almost no air coming out. A while ago, we had a minor work done on the duct going from the unit to the wall (to the house). He took off all the insulation padding and sealed the ducts with some kind of putty (I could be wrong I don't know too much about house stuff). I didn't notice much change then and two summers have passed.

I think it's really time for me to do something cuz one month my elec. bill came out to $500. But I don't know where to start or who to call to consult.

Can I reduct throughout with a narrower duct for easier(?) installation?
I think there's definitely a leak somewhere because one side of a wall is cold whenever I have the a/c unit on. Hopefully that has each room with stronger air flow.

Then, I want to control each floor separately because temperature difference is too big to just do so with 1 thermostat. I read somewhere that if I wanna do multizone I need to install baffle to direct each flow to each zone.
If I can do that much then maybe I can finally install z-wave thermostat with z-wave controlled vents to control temperature down to each room.
Is my approach too far fetched? unrealistic? expensive?
Sorry for the long messy explanation. Please help.

Best Answer

I would recommend first contacting a home energy efficiency company first rather than an HVAC company. HVAC guys are usually clueless about systemic problems like these and will usually try to sell you a larger unit without diagnosing the true cause of the issue (which is a pain in the neck and can probably be fixed for much less than the cost of new equipment).

It sounds like you have two problems: Poor duct pressure and temperature stratification. These are likely caused by the same thing: conditioned air escaping or being wasted in some manner. A common cause is ductwork running through an unconditioned attic. For example, in a ranch house, if the A/C unit is on one side of the house, the register on the far side will often not be very cold because the heat of the attic is sucking out all the coolness in the ducts!

This is the kind of thing that is virtually impossible to diagnose over the internet. I would recommend contacting a local energy efficiency & retrofit firm.