40-Year-Old AC Replaced with Daikin DH6 Heat Pump
Cold Cloud Mechanical replaced a failed 40-year-old AC and gas furnace with a 3.5-ton Daikin DH6 heat pump, relocated the air handler to the attic, redesigned the ductwork with Manual J and Manual D, and helped the homeowner qualify for a $3,850 LADWP rebate.
From a failed legacy AC to a modern all-electric heat pump
A homeowner in the 90065 ZIP code, in the Glassell Park and Mount Washington area, called Cold Cloud Mechanical after their air conditioner stopped cooling. The system had been on the property for roughly four decades and was paired with a gas furnace inside an interior closet.
On arrival, the system diagnosis found a failed compressor and a refrigerant leak in the original lineset, which used aged rubber hose construction. Instead of patching an obsolete platform, the project shifted toward full replacement: remove the gas furnace, install a Daikin DH6 heat pump, relocate the air handler to the attic, and rebuild the duct system around the home’s actual loads.
Why repair was no longer the right option
Two failures pushed this project from a repair conversation to a full replacement: the compressor was no longer functional, and the original lineset was leaking through aged rubber hose construction that had reached the end of its useful service life.
The refrigerant circuit was compromised
The old system had a failed compressor and a leaking original lineset. Refurbishing would have meant investing in outdated equipment with compromised refrigerant infrastructure.
The homeowner wanted to reclaim interior space
The old gas furnace occupied an interior closet. Relocating the new matched air handler to the attic allowed the homeowner to regain storage space while modernizing the HVAC system.
What Cold Cloud Mechanical completed
The project included old equipment removal, heat pump installation, attic air handler relocation, refrigerant lineset replacement, 3D scan, Manual J load calculations, Manual D duct design, and full ductwork replacement.
- Removed the failed 40-year-old air conditioner and the existing gas furnace.
- Installed a new Daikin DH6 heat pump system sized at 3.5 tons.
- Relocated the air handler from the interior closet to the attic.
- Performed a 3D scan of the home as the basis for the duct redesign.
- Ran Manual J load calculations to confirm room-by-room cooling and heating demand.
- Ran Manual D duct design to size and route new ductwork for correct airflow at each register.
- Replaced all ductwork and corrected code violations found in the existing duct system during the rebuild.
- Installed a new full-length refrigerant lineset to replace the leaking rubber-hose original.
- Removed the gas furnace from the system entirely, converting the home to all-electric heating and cooling.
- Reclaimed the closet space previously occupied by the indoor HVAC equipment.
- Completed system startup, commissioning, diagnostic checks, and performance verification.
$3,850 LADWP rebate value for the homeowner
This project qualifies for the LADWP Consumer Rebate Program for heat pump installations at $1,100 per ton. On a 3.5-ton system, that creates a rebate value of $3,850 for the homeowner.
Heat pump installation rebate value based on the system capacity.
Total rebate value for the 3.5-ton Daikin DH6 heat pump conversion.
Daikin DH6 heat pump, attic air handler, and new ductwork
The final installation replaced the old AC and gas furnace with one modern all-electric system that handles both heating and cooling, supported by a new lineset and duct system designed around real airflow targets.
Daikin DH6, 3.5 tons
New Daikin DH6 heat pump system sized for the home’s cooling and heating loads.
Matched Daikin air handler
The indoor air handler was relocated to the attic to reclaim interior closet space.
New full-length lineset
The leaking original rubber-hose lineset was replaced with a new refrigerant lineset.
Manual D-designed supply and return ductwork
New ductwork was sized and routed to deliver correct airflow at each register.
Replacing old equipment without duct redesign would have left comfort problems behind
A 40-year-old cooling system in Los Angeles is not just inefficient. It is usually tied to obsolete refrigerant, a deteriorated lineset, aging controls, and ductwork that was never balanced to the rooms it serves.
By moving to a Daikin DH6 heat pump, removing the gas furnace, relocating the air handler to the attic, and rebuilding the ductwork around Manual J and Manual D numbers, the homeowner now has one modern system for both heating and cooling — plus reclaimed closet space.
Before, during, and after the 90065 heat pump conversion
The photos below show the old gas furnace, existing electrical panel, outdoor unit replacement, attic-mounted air handler, new disconnect and wiring, startup, diagnostics, and before-and-after conversion.
All-electric heating and cooling with reclaimed interior space
The project replaced an obsolete AC and gas furnace with a modern Daikin DH6 heat pump system, rebuilt the ductwork around room-by-room load and airflow requirements, and moved the indoor equipment into the attic.
Modern heat pump comfort
The Daikin DH6 now provides both heating and cooling from one all-electric system instead of relying on a separate gas furnace and old AC.
Rebuilt duct performance
New supply and return ductwork was designed with Manual D after Manual J load calculations confirmed the home’s room-by-room demand.
Closet space reclaimed
Relocating the air handler to the attic gave the homeowner back the interior closet space previously occupied by the old furnace.
Planning a heat pump conversion?
Cold Cloud Mechanical designs heat pump conversions around real load calculations, duct design, equipment placement, rebate opportunities, and the comfort problems the old system could not solve.