HVAC Dampers

/ HVAC Dampers #1  

wngsprd

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Apr 6, 2004
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Location
Beaverdam, Virginia
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Kubota L3130 DT
I have what looks like 2 faulty electic zone dampers in my HVAC ductwork. The HVAC company quoted about $1,500 to replace them which seems much too high (especially since they just replaced my geothermal heat pump system for mega bucks back in March).

So, I am looking into a do it yourself job. Anybody tried this or have experience and can provide any tips or gotchas to watch out for? Thanks!
 
/ HVAC Dampers #2  
Need more info. Are they faulty dampers or faulty actuators? What controls them? What are they accomplishing? Are they on thermostats?
 
/ HVAC Dampers
  • Thread Starter
#3  
They are controlled by a central programmable thermostat system that monitors temp in 5 zones of the house. I haven't tested them but believe the motors may be bad.
Thanks for help!
 
/ HVAC Dampers #4  
Do the motors just bolt onto a shaft? I assume they are operated with24 volts. How many wires go to it? If it takes a 2-10 volt or something signal you need to see if it is getting a signal.
 
/ HVAC Dampers
  • Thread Starter
#5  
Thanks again Professor Marvel. I have tried to attach a photo of two different damper units to show the motor and wiring config. I beleive they are recieiving a signal, and will test.
 

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/ HVAC Dampers #6  
Oh yes. It sure looks even at a first glance that the actuator motor is a problem. You must have a pretty sophisticated residential system. Is your fan variable speed or is there a bypass damper in the duct work?
KMC MEP-5223 Direct-Coupled Replacement Damper Actuator is 1 place that looks like they would have a replacement for you. Also (not sure where you live) but a local AIRECO could probably help you out. They have locations in Va and Maryland.
Power down your controller while you replace the actuator so you do not short anything and ruin your controller. It certainly looks like a job you could tackle yourself to save a chunk of money like that. Use your picture to get the wiring right. In case the configuration is different make sure you get the right wires on the COM, CW and CCW terminals.
 
/ HVAC Dampers
  • Thread Starter
#7  
The system has a variable speed fan and is pretty sophisticated - certainly more sophisticated than me. Thanks again for your help and even providing the link to the site with the accuator. I'll check with Aireco in Ashland or Fredericksburg.
 
/ HVAC Dampers #8  
You are certainly welcome. Actually I do commercial HVAC controls for a living and I am impressed how advanced the residential market is becoming. I am just glad that for once I am knowledgeable about a question on TBN. Good luck and it looks like you are right about saving yourself a good chunk of a 1500 dollar bill.
 
/ HVAC Dampers #9  
Looks like you may have some moisture issues that could have caused your problem. You should't have any problems replacing the damper assy.:thumbsup:

It's good to be able to DIY & save some $$$:D


Good luck
 
/ HVAC Dampers
  • Thread Starter
#10  
I got today off work, so am getting ready to take the accuator off the damper and take to Aireco - I called them and they said they won't sell me a new one since I'm not a contractor. But they did say they would look at the old one and confirm which model to get to replace it to replace it. I think it will be the one Professor Marvel provided the link to. I guess I'll try ordering from a website. Anyone have a recommendation?
 
/ HVAC Dampers #11  
You could try AmericanHVACParts.com. I purchased some parts for my Honeywell electronic air cleaner from them.They were very helpful with my questions which is not always the case with DIY HVAC.

Some of the HVAC forums are pretty specific that HVAC should be left to the pros only so read the site warnings before you post or you may get flamed.

You might also try www.diychatroom.com...I have found some very good info and helpful posters there. The information I found on their site saved me about $1500 on a variable speed fan repair.

Steve
 
/ HVAC Dampers
  • Thread Starter
#13  
I just wanted to thank all, and especially Professor Marvel. I ordered exactly the part you suggested from the website you shared. Now that it has been working great for a couple of weeks, I'm ready to declare victory. This DIY saved me $100's. Thanks.
 
/ HVAC Dampers #14  
Great to hear. That's what we are here for.
Merry Christmas
 
 
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