Boiler vent damper not closing


  #1  
Old 03-23-17, 05:58 PM
K
Member
Thread Starter
Join Date: Mar 2017
Posts: 5
Upvotes: 0
Received 0 Upvotes on 0 Posts
Boiler vent damper not closing

Hi, i have a vent damper that is stuck in the open position occasionally and causing the boiler to fail to start. Even though it is in manual override the boiler gives me the same error code as if it were trying to close the damper. I've read that it is possible to jump this vent damper so that it stays in the open position. I'm a novice so where do i get a jumper cable for this??? Can i buy it at HD?Or is there any other way to bypass this vent damper?? Vent damper model GVD-7.

Thanks for your help.
 
  #2  
Old 03-24-17, 06:36 AM
B
Member
Join Date: Oct 2015
Location: Ct.,USA
Posts: 3,331
Received 314 Upvotes on 277 Posts
Intermittent problems are difficult and usually solved by elimination. The following is a method to eliminate a possible source.
By placing the manual override switch in the open position, your closed damper should open automatically (mechanically operated by a spring). The damper should operate a position switch when fully open. The position switch action signals the furnace control to continue the start up sequence. Therefore there are operations after the damper is open that need to be satisfied before the furnace will start. I will assume these other operations are operating properly.
The vent damper can be checked by observing an indicator (pointer or some other mark on the vent damper shaft) on the drive shaft of the vent damper external to the vent pipe. If the pointer or mark is aligned with the center line of the vent pipe, its orientation is correct but may not be operating the position switch. Try manually rotating the shaft in the direction of damper open to see if the furnace will start. If it does, this indicates the shaft has too much friction and needs lubrication. If it doesn’t the position switch could be bad or there is some other operation at fault. Hope this helps.
 
  #3  
Old 03-24-17, 08:31 AM
D
Member
Join Date: Apr 2014
Location: us
Posts: 1,350
Received 105 Upvotes on 99 Posts
Most of the motor assemblies are held on by 2 screws.

Remove the assembly and rotate the vent damper shaft by hand.

While there should be some resistance/stiffness as it reaches fully closed, there is a limit to what the motor torque can do. The tiny gears in the clock type motors often wear and strip.

Also when removed, electrically activate it and look for normal and abnormal operation.
 
  #4  
Old 03-24-17, 04:04 PM
K
Member
Thread Starter
Join Date: Mar 2017
Posts: 5
Upvotes: 0
Received 0 Upvotes on 0 Posts
Thanks for all the replies. Just curious if I wanted to jump the cable to test the vent damper, as the instructions explain, where and what is the jumper cable called? Can i find it at home depot? I tried googling it with no luck.

Thanks!
 
  #5  
Old 03-24-17, 04:27 PM
G
Member
Join Date: Oct 2008
Location: USA
Posts: 2,606
Received 28 Upvotes on 27 Posts
If it were me, I'd just replace the vent damper if you've eliminated the other likely possibilities.
 
  #6  
Old 03-24-17, 05:10 PM
S
Member
Join Date: Oct 2013
Location: United States
Posts: 2,768
Received 141 Upvotes on 133 Posts
Without pics it's hard to tell but I'm assuming you have gas and there is a molex connector (plastic connector) on the vent. Disconnect the molex connector and since it's only 24v you only need a piece of thermostat wire or anything small enough to fit into the terminals. You only need to jump 2 terminals.

You will have to find the right pair by trial and error. When you find the right 2 the boiler should start. Don't worry about trying different configurations to find the right 2. Nothing will happen if you are wrong.

Hope this helps a little.
 
  #7  
Old 03-24-17, 08:38 PM
D
Member
Join Date: Apr 2014
Location: us
Posts: 1,350
Received 105 Upvotes on 99 Posts
Just curious if I wanted to jump the cable to test the vent damper, as the instructions explain, where and what is the jumper cable called? Can i find it at home depot? I tried googling it with no luck.
The common way to jumper electrical things is with "clip leads". A length of stranded wire with alligator clips at either ends. You can easily make them yourself.

HomeDepot does not carry them. HarborFreight, Autozone and Radio Shack do. Here is Amazon's:

https://www.amazon.com/SE-TL10-10-Pi.../dp/B0002KRABU
 
  #8  
Old 03-24-17, 09:33 PM
K
Member
Thread Starter
Join Date: Mar 2017
Posts: 5
Upvotes: 0
Received 0 Upvotes on 0 Posts
Perfect thank you for all the help!
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: