Problem:
There are a few diagnostics associated with Relief and Economizer/Outdoor Damper control. All will be troubleshot in the same manner. Please see IntelliPak Symbio 800 Troubleshooting for a full list of all Diagnostics associated with Damper controls and their trigger conditions.
Troubleshooting:
The damper is controlled by a 2-10 VDC signal sent to the actuator's input (SIG) from the Damper Control LLID. The unit's Damper Control LLID receives this signal feedback from the actuator's Feedback (U) output. It is essential that the 2-10 VDC output reading remains within 10% of the feedback reading from the actuator.
Preliminary Checks
With the Unit Stopped, verify the dampers actual positions.
OA Bypass - 100% open with a Command of 0% (ERW option)
Relief/Exhaust Bypass - 100% open with a command of 0% (ERW option)
OA Damper - 0% closed with a command of 0%
Exhaust Damper - 0% closed wit a command of 0%
Return Air Dampers - should be 100% with an OA damper command of 0% (ERW option or Title 24 units IPAK II)
If the damper position is not oriented correctly this can usually be corrected by switching Control Reversing Switch potentiometer on the actuator.
Confirm in Settings>Units Settings>Service Settings actual Min and Max Voltages settings. Default settings are 2 and 10 VDC respectively.
Check Voltage Readings at 0% damper Command
Following checks assume Min and Max Voltages are set to Default settings.
Measure the voltage between the 2-10V DC Out at the Damper Control LLID, voltage should be 2VDC.
If no voltage is read, disconnect the harness from the LLID and measure directly to the corresponding pins on the board. If 2 VDC is read at the pins on the board, there more than likely is short in the connecting wiring or actuator. If 0 VDC is read, the LLID will need to be replaced.
Measure voltage between 2-10V DC Feedback, voltage should be 2 VDC. If not refer to Figure 1 to verify wiring, intermediate harness connections and actuator to verify where you are dropping the voltage reading.
Please verify that the polarity of readings match. If one reading is negative and the other reading positive than more than likely you have crossed wiring between the SIG and COM connections.
If you are reading 2VDC at Output and Feedback
Go to Manual Override and command the dampers to 50% command. Dampers should open/close to 50% position. You should read 6 VDC at the Damper Output and Feedback inputs and VDC readings should be within 10% of each other.
If dampers do not open/close:
- Check if dampers are binding
- Check that the actuator’s linkage is securely connected to the damper shaft.
- Verify 2-10VDC Output and Ground is reading approximately 6 VDC
- Verify if 6V DC is making it to the actuator at SIG and COM wiring (see your schematic).
- If you have VDC at the actuator but actuator does not open, replace actuator. -
If no issues are found at 50% command increase the command to 75, 100% and repeat previous checks.
Bad LLID Determination
It is essential to verify the alarm conditions that trigger the specific alarm in order to determine whether the LLID is faulty. Please refer to the IntelliPak Symbio 800 Troubleshooting Help Center case for further guidance. However, if all VDC readings between Output and Feedback are within 10% of each other at 0%, 50%, 75%, and 100% checks, and the VDC readings do not exceed the thresholds that activate the alarm, the LLID will require replacement.
WARNING:
Information in this article is intended for use by individuals possessing adequate backgrounds of electrical and mechanical experience and who comply with all federal, state, and local laws, rules, orders, or regulations related to the installation, service, or repair of a heating or central air conditioning product. Any attempt to install, service, or repair a heating or central air conditioning product may result in personal injury and/or property damage. The manufacturer or seller cannot be responsible for the interpretation of the information contained herein, nor can it assume any liability in connection with its use.