Temperzone controllers - Hanwest Han-L5
Han-L5 Controller
The Han-L5 controller was used, from the late 1990’s until early 2000’s, in Temperzone and Bradway air conditioners throughout Adelaide and Australia. This controller is now obsolete and cannot be purchased as new from suppliers. Second hand products are occasionally available but generally unreliable.
Features
- Black display screen with green lettering
- Slide switch to change modes (Heat/Cool/Dry/Fan)
- Clock feature
- On and off timer for preset unit operation
- Power failure auto on feature
- AAA battery clock back up
Hints, Tips and Problems
Remove the batteries.
This will stop the controller from saving the clock time if you have a black out but will help prevent the batteries leaking and the battery acid eating the electrical components in the back of the controller. This will also help prevent the controller turning on after a blackout. The batteries tend to automatically switch the air conditioner back on once power is restored.
Flickering display.
As the Han-L5 controllers age, the green lettering tends to flicker while in use. This is pretty normal and will get worse with time. This is purely cosmetic and will not affect operation until the display is unreadable.
Buttons not changing correctly.
This is also very common with Han-L5 controllers and DOES affect operation. The most common version of this fault is the temperature up/down buttons switching the timer function on. When the temperature buttons are pressed, the ‘off’ timer is switched on. This can usually be changed by switching the timer back off if accidentally switched on (cycle all of the way to 12 then — will be displayed, this means timer is now off again).
Temperature display is really high 40 + deg C.
Generally indicates the temperature sensor has failed within the Han-L5 controller. This will prevent the system from heating in winter and will cool continuously in summer. A new remote sensor will need to be run down the wall and plugged into the back of the wall controller to fix this problem. The new sensor needs to be installed in a good location to allow correct temperature control (eg return air duct).
No screen display after power failure.
This is a somewhat common fault with the Han-L5 controller. Even during a simple service of the air conditioner, a technician can switch the power off to the unit and when switching power back on, the Han-L5 controller will no longer function. The controller does not reset after the power failure and will potentially never operate again. There is a reset procedure that can sometimes allow the controller to reset but does not always work.
Repairs/replacement.
Unfortunately the Han-L5 cannot be repaired easily and replacement parts are no longer available. A new sensor can be installed to rectify sensor failure issues and can be plugged into the wall controller. Any other issues with the Han-L5 will result in a new controller system. This will require the replacement of the wall controller, Indoor PC Board and interconnecting cable.
The new controller to replace the Han-L5 is the Hanwest, Han-L62. This controller will wire into the existing air conditioner but changes to the internal cabling need to made. A new cable also needs to be run between the new Indoor PCB and wall controller.
Cost.
With a qualified technician who knows what they are doing, the replacement of this controller is relatively straightforward. At T&K Airpower we replace 50 – 60 Han-L5 controllers a year and once you are familiar with the wiring, these controllers do not take long to replace. Replacement upgrade kits, with all components necessary, are approximately $550.00. The installation cost is around $500.00 – $800.00 depending on roof access. A total cost of between $1,000.00 – $1,400.00, including supply and installation, is pretty standard.
Some companies will try and replace these with no knowledge of how the Han-L62 is wired. We have had reports of over $1,800.00 spent by the homeowner and after many hours, the technician leaves the owner without a working controller. Ensure a fixed price is given before proceeding with a replacement installation and the installer ensures it works before leaving your home.
Conclusion.
The Han-L5 was a good controller and generally last 10-15 years without need for replacement. Although most parts cannot be replaced, the newer Han-L62 upgrade is worthwhile and brings some new features and an easier to use interface. Unless the Han-L5 controller fails and is no longer usable, your existing controller will serve you well. On the other hand, if the Han-L5 gives up and stops working, the cost of replacement is probably worth it over the $8,000-$10,000 for a new ducted air conditioner unit.
