Firing After a Long Cold Winter

[sholding]

My oven is 2 years old. We used the oven a lot last summer, and this is the end of it's 2nd winter. I'm wondering if we need to do the mulitple fires over several days to recure, or if 1 or 2 slow fires will be enough. It's still in the 30's outside, but I've had the temp up into the 200's in the last week. Does it seem reasonable that since the oven was dry in the fall, that we could fire the oven for cooking soon? (we don't have a cap on the flue- yet).
Thanks in advance for your advice!

[Neil2]

Re: Firing After a Long Cold Winter

It will depend on how much moisture got in over the winter.

To be safe, I would start with multiple smaller fires as if to "re-cure" it. You will be able to evaluate how dry it is as you go. Look for steam escaping from top (if you have an igloo with a small top vent) or unusual high heat on the dome surface (also indication of wet insulation). Also, having wet insulation will mean that it won't hold heat and this should be apparent after the first few firings.

[sholding]

Re: Firing After a Long Cold Winter

Thanks for your help with this. Would you agree that it's the moisture inside, and not the cold temp inside/outside that I need to be concerned about? I have a dome. The last firing, I had smoke/light in color coming out the flue, I'm not sure I could tell the difference if it were steam, could I?

[HeidiL2011]

Re: Firing After a Long Cold Winter

Hi Sholding

First, you need to take a good look and see if water got into the oven anywhere. If there are any signs of moisture, you should work out how it got in, and stop it from happening in the future.

If there are any signs of water, you should re-start the oven very slowly. Two 8 hour days with a small fire (300-400F day one, followed by 500F day two) should slowly bake out any water. If you light a fully hot fire (700F+) and the floor or dome are still wet, you run the risk of damaging the oven, or seriously shortening the life of the floor.

Second, If the oven is just damp from a damp winter, you should still fire the oven for 8 hours at a low temperature (300-400F) before bringing it up to high heat.


Thanks,
Heidi

[blacknoir]

Re: Firing After a Long Cold Winter

#183 why i like this site.. First couple firings haven't gone well, my guess is wet insulation under the floor after a long hard winter.. come here and of course I easily find multiple posts with great suggestions. Thanks guys!

[david s]

Re: Firing After a Long Cold Winter

if you have an igloo design and the insulation layer is damp, then the outer shell will be hot to touch. When dry it should be only cosy warm at most. If you have water underneath the floor it is really difficult to remove and a couple of firings and then a spell of a few days to let the moisture migrate to the rest of the oven is useful. Check to see if there is a crack where the outside dome meets the supporting slab. This is often a problem area where water can enter. Seal it up if you can with some flexible acrylic.
we have tons of rain here in Nth Queensland and drying the ovens after the wet season is is a routine procedure.

[blacknoir]

Re: Firing After a Long Cold Winter

I think my problem is my supporting slab is bigger then my dome and since it's concrete it wicks up that water when it rains or the snow melts. This then in turn gets wicked up by the insulation under the floor. The inside of the dome heats up nicely and gets clear but i can't get the floor to heat up like it used to.. i'm thinking of putting a layer of latex paint on the supporting slab to give it some water protection. At least until I get time to cap it with something non-porous.

[Neil2]

Re: Firing After a Long Cold Winter

"i'm thinking of putting a layer of latex paint on the supporting slab to give it some water protection"

Does it extend out beyond the dome ? If it does, you may also want to take an angle grinder to it and make sure it slopes slightly away form the dome.

[blacknoir]

Re: Firing After a Long Cold Winter

Thats a good idea. The original plan was to make a concrete countertop to go all the way around it. I did part of it for the front of the oven but it's so massive that I didn't finish for the sides and back. I spose I could just stop being lazy and finish it.. The countertop is sealed so no water gets through and if I put some caulking between it and the oven I think i'll be in better shape.

[david s]

Re: Firing After a Long Cold Winter

You will eventually get it dry again and your oven will fire normally. It is too late now, but I found adding an ad mix to the concrete supporting slab not only makes the concrete stronger, but also waterproof, so I always used it now. Likewise Neills suggestion of sloping the slab away from the dome slightly discourages water penetration under the floor. This is easy to do when you pour the slab. All you have to do is mound the slab up higher in the middle when you screed it off. Sorry too late now, but do it on the next oven you build.

[V-wiz]

Re: Firing After a Long Cold Winter

Recently i talked to a guy who sells and builds ovens. He suggested i use one of these to cure the oven. Electric Charcoal Starter-812-9137-S at The Home Depot

[Gulf]

Re: Firing After a Long Cold Winter

A plain old charcoal chimney starter works great too!

Check out Karangi Dude's Heat bead Method .

It gives you plenty of control to start slow and then later ramp up the heat toward the end of the cure.

[C5dad]

Re: Firing After a Long Cold Winter

Here is my solution. However, be sure to keep the flame on low or have something where the flame can impinge upon (several bricks.) If not, the flame hitting the dome may crack it (experience) Yes, in this pic I have a normal firing, but you get the idea I hope.

Just a standard weed burner attached to a propane bottle. My gas line is 16 feet long to ensure separation.

Best o luck!

[gsmith7712]

Re: Firing After a Long Cold Winter

Do all ovens get wet during the winter and is there a way to keep it dry?

[WJW]

Re: Firing After a Long Cold Winter

I would think you could tarp it...but that might look very good in your yard. I've got my oven covered with stucco and elastomeric paint. And I have a little roof over the parts likely to allow water to get into the oven.





I also have a vent in the back of the oven enclosure placed for the purpose of giving moisture an easy way out should there be water present when I fire.

My oven has "weathered" one winter, uncovered, with no indication of any moisture issues. That being said, we only get about 13-14 inches of rain per year here. Virtually all of it falls over the course of three months, but it's still not a lot compared to most places.

Bill