Question about VC Aspen wood stove

dug · January 26, 2011, 12:15:19 PM

I know at least a couple of people here own this stove so I was hoping some of you could help me figure something out.

The air intake on the back is thermostatically controlled and connected by a chain to a lever on the top- what is the right way to adjust this?

Right now I have it set so that when the stove is cold the air intake flap is almost, but not quite closed with the lever all the way to the right (facing the stove). When starting a fire I open it up all the way until the flue temperature reaches about 350 degrees and then close it to about the half way mark.

The thermostat will gradually close the air intake as the temperature rises but often times not fast enough. I have found that if I don't manually close it down in time I get over fires on this stove with flue temperatures reaching 700 degrees and stove top temps off the scale on my 850 degree thermometer.

Also, as the stove cools down I would think the air would start opening a bit but the thermostat keeps it completely closed.

I bought the stove used so there may be a problem with the thermostat, more likely operator error though.

ChuckinVa · January 26, 2011, 01:50:22 PM

Dug,
I have this same stove only mine is set up opposite of the way you described. When I have the lever all the way to the left facing the stove, I get more air. When I move it to the right I get less air.
CHUCK

January 26, 2011, 02:54:39 PM

Every VC stove I've seen is set up so when standing in front, moving the lever right closes the flap and moving the lever left opens the flap. Or towards the chimney provides less air, moving away from the chimney provides more air.

Quote...when the stove is cold the air intake flap is almost, but not quite closed with the lever all the way to the right

Depends what you mean by "cold". When our VC Aspen is cold (30, 40 degrees) the flap is still open quite a bit when the lever is fully towards the chimney, or open. Also when it is cold like when we arrive after an absence, the lever can not be moved fully left but the flap is full open. The thermo bimetal spiral has contracted so much that the lever can not move any more.

When the cabin is at a comfortable temperature and the air lever is fully towards the chimney, but there is no fire, I'm not really sure if the flap is closed or open at all. I just don't recall. It is possible it is slightly open then

When the control lever is fully in the open position I can not get the stove over 550- F or so, as a rule. I can make it go higher if I turn on the forced air feed fan. (not a VC thing; my own unauthorized mod). Is your thermometer accurate? Have you tried it in an oven as a rough check? I use an infrared thermometer which is accurate within a few degrees.

If I leave the control on our stove at the half mark it will eventually overheat the cabin most days. Once our cabin is warm I run it with the control set way over to the right (chimney) side. Most days.

With the cabin at 68 to 70 in the evening, I can load the firebox and leave the control full right (towards the chimney). The fire will carry through the night and in the morning the interior cabin temp will be around 66 - 67 F

I should add that VC does not recommend lengthening or shortening the chain. I did lengthen it one ball because it consistently kept our cabin (45) sq ft, no loft) too warm at the minimal setting. Lengthening one ball permitted the air flap to close more at any given temperature. That worked for us; not recommended to work for anyoner else.

I believe the reason they use a chain like that is to permit them to set up the control to be adjusted for variances in manufacturing of the bimetal thermostat control.

I'll also add that the control is not perfect but it works well. Back home years ago we had a different VC stove with the same control. We seldom ever moved the control once winter set in.

Even with the flap fully closed, I believe air to the secondary burn chamber is not cut off. That is not controlled by the main feed flap. At least that is the impression I have. Maybe read it someplace.

Perhaps an email to VC would clarify how to check on the proper chain length.

MountainDon · January 26, 2011, 08:43:42 PM

I wanted to add something. Your chimney is longer/taller than mine. That will affect the stove draft, so your thermo control settings will be different. There should be a spot that works reasonably well for you though. I have to remind myself at times that the wood stove thermostat is not as precise as one for a gas furnace.

Pine Cone · January 27, 2011, 12:33:28 AM

I don't have any experience with the Aspen, but I used two different VC stoves as my only heat source for 6 years.

I had a Reliant or Defiant in a poorly insulated 2-story A-frame, all uninsulated black 8" pipe until it passed though the peak of the roof. It worked great and I can't ever recall needing to adjust the thermostat more than a few times a week unless I put way too much wood in. Not good to see your stove glowing red-hot, although it is an interesting, scary look.

I started a fire in September or October and kept the stove going 24/7. It would burn out if I was gone for 2 or more days, but otherwise always had a fire in it until sometime in May. The long chimney didn't seem to phase it at all, but maybe the newer EPA-registered stoves don't work as well.

After that I moved to a different house and bought what I think was a Resolute. This house was not as tall, and I used 6" double-walled pipe mostly. Again I never fussed with the thermostat much.

Given your earlier problems, I think I might try using a vacuum cleaner and alternately try to suck and blow though the intake and see if you might have some sort of blockage. I never had to fuss with the older stoves much and they worked incredibly well.

January 27, 2011, 11:53:52 AM

QuoteEvery VC stove I've seen is set up so when standing in front, moving the lever right closes the flap and moving the lever left opens the flap. Or towards the chimney provides less air, moving away from the chimney provides more air.

That's how mine is too, I guess I just described it wrong
.

QuoteI should add that VC does not recommend lengthening or shortening the chain.

I've been fiddling with the chain length for awhile now so I'm not sure where it originally started, or whether it was even right then (used stove). I tried setting it more like you described last night.

QuoteInsert Quote
I wanted to add something. Your chimney is longer/taller than mine. That will affect the stove draft, so your thermo control settings will be different.

It does seem to have an especially strong draft. I'm thinking of adding a damper for a little added control.

QuoteGiven your earlier problems, I think I might try using a vacuum cleaner and alternately try to suck and blow though the intake and see if you might have some sort of blockage.

I did vacuum the whole thing out real good and the problem I was having earlier on with this stove is not happening now, in fact pretty much the opposite. Before I could hardly keep the fire burning, now I am usually concerned about it getting too hot. I'd like to be able to load it at night and not worry about the temperature spiking a half hour later.

I checked my thermometer in my oven last night and it did read a little high. The oven was set at 350 and thermometer reading 425, so almost 20% off. But I've always suspected my oven to be inaccurate as well, and set it 10% lower than recommended when baking. So who knows?

Guess i'll get a new thermometer of maybe one of those fancy IR guns.

Don, does your flap ever start to open as the fire cools down? Mine seems to just gradually close down until it is all the way shut and stays there. I was thinking that more air should be added as it cools.

MountainDon · January 27, 2011, 03:16:29 PM

Quotedoes your flap ever start to open as the fire cools down? Mine seems to just gradually close down until it is all the way shut and stays there. I was thinking that more air should be added as it cools.

I can't see the flap because of the fresh air shroud. But it must be opening or closing as the fire changes as it can be set to burn slowly through a firebox full of wood. I believe that as the stove cools and the room cools then the flap will be moved by the thermo control to allow more air to enter. If the fire is almost out the flap should be open some for certain.

I'd like to help more but don't know how.

OlJarhead · January 27, 2011, 10:33:39 PM

When I arrive at the cabin I move the lever to the left. It then moves back to the right and I ignore it

I then prime the stove/chimney (I have two 90 degree angles in my install and the chimney is pretty tall) and then light a fire in it.
I then leave it.

Usually after the first 24 hours if it's warm enough inside the cabin I'll move it half way and then ignore it again.

The only time I've ever moved it to the right was when it was only 32 outside, then it was fine to let the stove cool down a bunch.

But I should note that I'm burning Ponderosa Pine and I doubt the stove will ever get really hot with this fuel!