SMW Refrigeration and Heating recently finished work on a property in north Phoenix.  This was a pretty complicated project and involved completely rebuilding the entire HVAC system in the home.

ac project outside

Pictured Above. Outside of home when project started.

Expanding The Home, Insulating It And Determining Tonnage

Originally the home had a single 5 Ton Split Gas AC System on it. The duct-work connected to an underground return duct, and a supply trunk in the hallway soffit. The home was purchased and the interior was completely gutted. Plans were then drawn up, expanding the area of the home from 2200 square feet to 3100 square feet. New energy efficient windows were installed, and the walls and attic were insulated with spray foam.  These changes to the shell of the building made performing a load calculation necessary to determine the size of equipment needed.  The relevant data was collected, and the home was modeled in Wrightsoft load calculation software. The results of the load calculation revealed that the size of air conditioner needed for the home was going to be a 4-ton unit for the east side and a 3-ton unit for the west side. Wrightsoft also sized the duct system for the home.

Insulation Specifications

Part Of The Home Insulation
Walls (Existing) 4″ Brick Fired out and Spray Foamed
Walls (New) 2″x6″ Wood Frame with Spray foam in Attic
Attic Encapsulated With Spray Foam
Windows Dual Pane Simonton SHGC 0.23/Value 0.29
Foundation Existing Concrete Slab

Zoned XV20i AC System & Accessories For The Project Install

The customer opted for two variable speed Trane XV20i heat pumps paired with communicating Trane Hyperion Air handlers, one 4-ton and one 3-ton, each controlled with its own XL950 7″ touchscreen thermostat. The previous air conditioner used gas heat but the owner went with heat pumps because it doesn’t get that cold in Phoenix.
  • The 4-ton system was divided into two zones using Trane’s Comfortlink zoning system. The master bedroom suite was placed on its own zone, and the rest of the west side was placed on the other zone.
  • The 3-ton System was designed to cool the expanded great room and the kitchen area but was not zoned.

Both systems were connected to an R-8 flex duct system that was sized according to ACCA Manual D procedures. Installed into the supply plenums of each unit was Activtek Induct 2000 UV lights to help clean and disinfect the air in the home. SMW also installed super quiet 80 cfm Delta Breeze Greenbuilder exhaust fans in all the bathrooms and laundry room, and a special Panasonic 110cfm Whisper Warm Fan with a built-in 1400 watt heater in the master bath. The roof venting for the dryer and rangehood were also provided by us.

Air Conditioning Equipment

The table below outlines all the air conditioning equipment chosen

Part Equipment Model
Condensing Unit 4 Ton and 3 Ton Trane XV20i Heatpump
Air Handlers Trane TAM8 Hyperion
Thermostat XL950 with Comfortlink II Zoning
Air Cleaner Activetek Induct 2000
Ductwork R-8 Flex
Grilles Bar Type Return OBD Supply
Exhaust Fans Panasonic Whisperwarm/Delta Breeze Greenbuilder
xv20i ac condenser

XV20i AC condenser pictured above

ductwork interior

Pictured Above. Duct work being installed.

Stages Of Installing The Equipment

Mechanical Plans were drawn up then submitted to the city of Phoenix for a building permit, meanwhile, SMW waited for the call to start the work and made plans to do the installation in 3 Stages.

  1. First, the air handlers, linesets, ductwork, register cans, and exhaust fans were installed in the home.
  2. The second stage consisted of installing the condensing units, and all the grills for the ductwork and filters.
  3. Lastly, the thermostats were done, the new AC units were fired up for the first time, and the refrigerant charge was set.

However, once the install was complete two more things needed to be done.

  1. SMW completed an air balance on the home, testing the airflow to each room to make sure that the air conditioner met all the values from the load calculation.
  2. Finally, blower door testing was performed on the home, to test the air tightness of the home and ductwork.

Starting with patient planning and then getting proper permission from the city, we successfully installed the new AC units and saw that they performed to desired specifications.

hvac mechanical plan

Mechanical plans for the HVAC equipment pictured above. Click to get a better look.

The homeowner is very satisfied with the quality of work done.  If you have a similar project, give us a call, email us the plans, and we can quote your project.