Hello all!
Helping a friend with her Heat Pump / Air Handler... Coil froze over due to fan problem - Technician quoted a new system based on its age and the blower being an ECM with estimated cost to replace at ~$1500.
Based on my troubleshooting - ECM Motor tests good - no shorts from any terminal to frame / ground and each winding reads 13 Ohms. Similar tests described in below link for the controller.
https://s3.amazonaws.com/s3.supplyho...TL-Install.pdf
We thought the thermistor may be bad on the control board - worth a try at $7 - but did not resolve the issue.
Awaiting delivery of the new part, but... I noticed that the control of the ECM motor can also be via PWM (Pulse Width Modulation) - I assume of the 24 VAC signal?
There is a separate control board - with one terminal for the speed tap - which I assume is providing the PWM - may skip that board altogether if suggested.
When testing with voltmeter - It did appear the fan control input was beeping repeatedly (PWM) and attached to the #3 terminal.
The installation manual also suggests you could connect directly to a speed terminal without PWM.
I guess my question is...
- Likelihood of the PWM controller causing a failure? Is there any way to test?
- Is there a specific tap to use PWM - Probably #3?
- Anyone suggest just skipping the PWM board altogether?
Thermostat is Ecobee 3 Lite - assuming I will just connect the fan control to the motor - and let the Ecobee manage.
Thanks in advance!
Helping a friend with her Heat Pump / Air Handler... Coil froze over due to fan problem - Technician quoted a new system based on its age and the blower being an ECM with estimated cost to replace at ~$1500.
Based on my troubleshooting - ECM Motor tests good - no shorts from any terminal to frame / ground and each winding reads 13 Ohms. Similar tests described in below link for the controller.
https://s3.amazonaws.com/s3.supplyho...TL-Install.pdf
We thought the thermistor may be bad on the control board - worth a try at $7 - but did not resolve the issue.
Awaiting delivery of the new part, but... I noticed that the control of the ECM motor can also be via PWM (Pulse Width Modulation) - I assume of the 24 VAC signal?
There is a separate control board - with one terminal for the speed tap - which I assume is providing the PWM - may skip that board altogether if suggested.
When testing with voltmeter - It did appear the fan control input was beeping repeatedly (PWM) and attached to the #3 terminal.
The installation manual also suggests you could connect directly to a speed terminal without PWM.
I guess my question is...
- Likelihood of the PWM controller causing a failure? Is there any way to test?
- Is there a specific tap to use PWM - Probably #3?
- Anyone suggest just skipping the PWM board altogether?
Thermostat is Ecobee 3 Lite - assuming I will just connect the fan control to the motor - and let the Ecobee manage.
Thanks in advance!
source https://hvac-talk.com/vbb/threads/2242826-Genteq-Evergreen-EM-Control-Module-6205ECTL?goto=newpost
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