Wait a Minute!....Icicles on My Cap!!!

[BurnIt13]

This is a new one for me. I searched before I posted this an read some informative threads but figured I'd need to share my thoughts anyways. The threads I found were either from the Blaze King crowd or idiots who smoldered 70lbs of two week old oak in a smoke dragon.

Its been chilly here lately and from Friday AM to Monday AM the temps never got out of the teens and single digits at night. Saturday night we had a small snow storm dump nine inches so Sunday AM I went out to shovel and found.......ICICLES ON MY CAP

My first reaction was horror. I was having fears of a gooey mess clogging up my cap. I went inside and started searching hearth.com and started to feel better. I guess I'm still looking for someone to pass me a beer and tell me everything is normal.

I go through 2.5-3.5 cords of wood depending on the severity of the winter. I sweep at the beginning of the year and then halfway through. Sometimes twice if I'm skeptical of my wood. I've gone through about a half a cord so far this winter. Many of this has been chunks and uglies, a few of which have been punky or a little wet from sitting close to the soil.

I have been dialing down my fires more than I have in the past couple of years. So far no smoke during the main part of the burn. I've been keeping my flue temps (probe) close to 400-450 and my stove top around 500. What concerns me is that 10ft of my double wall is exposed after it exits the roof, so it has plenty of time to cool down.

Should I be nervous? Are icicles common? Does that mean my stack temp is very low at the top of the chimney? Should I run it a bit hotter?

For what its worth, the icicles were not very dark colored...just looked a tad dirty.

Am I crazy?

 

[mellow]

High wind and cold temps can freeze just about anything.

 

[oldspark]

. I've been keeping my flue temps (probe) close to 400-450 and my stove top around 500. What concerns me is that 10ft of my double wall is exposed after it exits the roof, so it has plenty of time to cool down.

Thats on the low range of the safe zone.

 

[BurnIt13]

Yep....I think we all try to run our stoves filled with the most wood possible and with the least temps possible though right for the longest burn? I've got a condar probe thermometer and magnetic stove top thermometer and an IR gun that I'm constantly waving all over the place. I'm constantly staring at them and my wife thinks I'm nuts. (She may be right).

I'm starting to think 400-450 flue temps would be okay if
1. You have perfect wood.
2. Most of your chimney is internal.

I'm worrying that because I've got 10ft of it exposed and my wood is 18-22%, I'd be better off running a little hotter at 500-550 (flue) degrees just to be safe.

 

[oldspark]

Since you have an IR testor you know how much the temp can drop off in just a few feet, at 18 inches above the stove I can have 650 (surface temp single wall, have had high flues temps with this stove since it was installed) but about 2 and 1/2 to 3 feet about that its only 450 going into the class A,
What do you suppose it is by the time it gets up the pipe another 15 feet or so, the class A pipe is insulated but there still be some temperature loss.

 

[BurnIt13]

Exactly....which is why I'm worried and started this thread. For what its worth for this discussion I have about 5ft of double wall stove pipe going into about 17ft of double wall stainless. It is about 23' from the top of the stove to the top of the cap. That is a long way to go, and plenty of time for things to cool down.

 

[Slow1]

I get ice on my cap pretty regularly. As soon as I reload they fall off during the heat up time - I can hear them fall sometimes and clunk against the house (I have a SS external Class-A chimney going up the side of the house).

To the best of my knowledge this hasn't been a problem and my chimney has been pretty clean each year.

I think that the cap is just very cold up there (cools off quickly with cold air) and once the stove has settled into that final coal burning stage not a lot of heat goes up the chimney but it is high humidity allowing the condensation to form on the cap and drip down forming the ice.

 

[EatenByLimestone]

Run your stove a bit hotter. It's supposed to get down to 3 here tonight and I'd hate to lose the stove. Fix the issue while you can.

 

[BurnIt13]

Yep. I think I'm just going to have to adjust my burning habits. The colder it gets outside, the hotter I'll make my stove inside. It is supposed to be around 2F here as well so it won't hurt to run the stove a bit hotter.

I'm burning through some pine though.......so I expect to be chilly when I wake up tomorrow AM. I love pine but it just doesn't last as long.

 

[BrotherBart]

This pic from several years ago is the chimney connected to a PE Summit that is always burned hot and clean.

 

[BurnIt13]

That's about the same color as mine, maybe mine was a shade darker. Except I had about 3 of those and they were each about 18" long.

I wonder if it was because of snow melting on the top of the cap, dripping down then freezing on the side.....or moisture from the firewood.

 

[oldspark]

The icicles are not a problem, its just he is running on the low side of the safe zone, nice to have a little head room towork with.