Kuuma VF100 damper spring adjustment

[burtman4]

Last year I noticed my damper was not opening as it should, so I loosened the damper spring a little bit and it worked fine. Just fired up the VF100 for the first time this year and noticed the damper was not opening as it should again. Loosened the spring adjustment a little more and it seems to be working though, I would like it to cycle a few days to verify. I still have a little more adjustment to loosen it if I need. Looking at the VF100 manual, it states to loosen the spring if it isn't opening as it should.

My question is, has anyone had to adjust the damper spring over the years. Furnace was installed in 2017 and I used the damper set as it came from the factory.

 

[brenndatomu]

I had to adjust the spring on an older VF200 (same damper setup) but it was 10 years old or so...ended up buying a replacement stepper motor. You may be fine if you adjust yours again, but on the one I had I wasn't sure the spring was tight enough to make sure that damper would close on power loss...then I noticed that sometimes the motor would go from 3 to closed, when it should have went 3 - 2...talked to Lamppa and they said the motors can get weak after a while, so I replaced it...that solved the issue.

 

[burtman4]

Thanks! I was thinking the stepper motor may be getting weak as something had to change. Will contact Lamppa when I get a chance and look at getting a stepper motor.

 

[lampmfg]

This is very common. Our spring tends to get tighter over age, which is counterintuitive but normal. If you have to lower the pin more than 1/4", we should probably have the damper repaired. Thanks

 

[burtman4]

This is very common. Our spring tends to get tighter over age, which is counterintuitive but normal. If you have to lower the pin more than 1/4", we should probably have the damper repaired. Thanks

I only adjusted 1/8" or less this time. Last year may be the same, can't remember. Thanks for the info as work got into the way today and I couldn't call. It's working good right now and the spring has tension, though I will be in touch.