Outside air intake on EPA Master Forge wood stove.

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3650

Minister of Fire
May 8, 2011
932
midwest
I was looking at the outside air intake on this stove and it's a three inch stub coming out of the back of the stove. It only leads in to the ash pan area located in the pedestal of the stove. With the pan out, looking up at the bottom of the stove the only place for air to come in is the ash clean out on the bottom of the stove and it is plugged when the stove is burning. How in the world does outside air reach the firebox? It's like it's a faux outside air port. I even hooked up a draft inducer blower to the port and it made absolutely no difference to the flame inside. Turning on and off there is no effect on flame.
 
Typically, a draft inducer is put on the flue, not the intake. If draft is balky it could force CO out of the firebox and into the room.
[Hearth.com] Outside air intake on EPA Master Forge wood stove.

Don't do this. It will void the warranty on your new stove. The outside air connection is not directly connect to the air intakes. This is a safety feature. What is the reason for trying to push air into the stove?
 
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The stove ran pretty good for about three days but now I have to spend a few hours coaxing the morning fire to start. This morning I had a good bed of coals but Everytime I shut the door it just died. So I left the door open for about an hour to get it going and it still doesn't want to run very well after shutting down he door. I checked moisture in the wood and it was ranging 13-20%. Something doesn't seem right.

The whole thing with hooking up a blower to the outside air intake was just to see if more air to the firebox helped. This is when I discovered that there really doesn't seem to be a way for the outside air to reach the inside of the firebox. It just seems to dead end in the ash pan area.
 
Stove intakes don't just plug up. Something else is different.

What are outdoor temperatures? Draft increases strength when outdoor temps drop.

How is the wood's moisture content being tested?
 
Temperature has dropped in the last few days. I'm testing with the meter I got from Amazon. I don't recall the brand. Just a typical Chinese one. I did split the ones I checked and tested the fresh side.
 
I'm testing with the meter I got from Amazon.
How are you testing the wood? On the outside of the firewood or after resplitting the wood and testing in the middle of the freshly exposed face of the wood?
 
How are you testing the wood? On the outside of the firewood or after resplitting the wood and testing in the middle of the freshly exposed face of the wood?
The middle of a fresh split
 
The middle of a fresh split
OK, that's the right place to do it. We have to eliminate each possibility. There is still a possibility that some of the wood is a bit damper in the core than other pieces.

The next thing is to examine the flue system. Is there a screen on the cap?
 
How is the firebox being loaded, E/W or N/S?
 
How is the firebox being loaded, E/W or N/S?
North and south. I just looked at the flue two days ago and it had a small amount of creasote in the top two feet but everything else was clean beneath that. It's 6" insulated straight up through middle of house about 16 feet. No screen on the cap. The draft seems good. It pulls the smoke away easily when I open the door. I have a manometer I can put on it. What draft do you reckon these stoves should run at.
 
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What draft do you reckon these stoves should run at.
.04 to .1. is a typical range. The exact requirements for this stove are unknown.

It sounds like you are doing things right. Maybe try splitting a few 2x4 scraps in half and mixing them in with the wood?
Does opening a nearby window 1/2" improve the fire?

As a test you could try adding a temporary extension to the chimney by using a 4' section of 6" warm air duct pushed into the top. If that makes a notable difference, then add a section of chimney pipe. The chimney would then need a brace at 5' above the roof exit of the chimney pipe.
 
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I'll try a window. Not home at the moment. I've never had a low draft issue with this chimney. I had to use 2 manual pipe dampers on the other stove to sow it down. It's a good four feet above the highest point of the roof. I don't have many trees. I live on the prairie with high winds. I'll put the mano on it tomorrow and see what it pulls.
 
Agree it's odd. Does the air control feel the same? One slim possibility is that the linkage for the air flap it controls has come disconnected. We don't see a lot of this stove so you will have to inspect and tell us what you see. In order to see how it works, pull the ash bin and use a mirror or a cell phone to look up at the underside of the firebox while moving the air control.

Are the manual dampers still in the stove pipe? Even open they are going to restrict draft somewhat.
 
There is one manual damper. I thought I might need it because my chimney pulls so hard. I tried it out when the stove was running good and it had absolutely no effect on the flame. This baffles me. It is wide open now though.

I did pull the ash pan yesterday and have a look at the bottom of the fire box and it's just a solid steel plate. I didn't use a mirror though so I'll have another look. I may have missed something.

I think the linkage works properly because I can hear it sliding in the top back portion of the stove when I move the rod. I do notice a change in the flame when I push it closed or pull it open but the change is extremely gradual. That just didn't seem right to me from the beginning but I thought it must just be the nature of the stove.

I'd have to pull the pipe and look through the stove adapter to see it I think. Maybe removing the baffle and blanket will reveal it. I really should have inspected this closely before I installed it to try and get some ideas how it functions.
 
Moving the baffle may not show much of the air control, but now I see that this stove is an oddball for air control. Removing the back might reveal more. If that's where the air control shows, please take a picture.

This is for the Cleveland Ironworks model H & WS110. The LPAO appears to be boost air.

[Hearth.com] Outside air intake on EPA Master Forge wood stove.
 
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Yes that is the same stove. I saw on Enerco website that Cleveland, Master Forge and Grand Teton are all the same stoves. I'm glad you found that. This helps a lot. Now I know where to look more closely for air intakes.

I didn't have much time to do any troubleshooting today. Today is the sixth day off I've had all year so I had a lot of other stuff I had to attend to. Lots of errands to run. I did pick up two 20 packs of Gren bio logs. When I got home I threw 6 in on top of the small pile of coals that were left and low and behold the stove took right off. I was in cruise control after about 15 minutes. This tells me the wood I have uncovered in the wood pile is off. I guess my moisture meter is bad. I have another one I got from harbor freight about 15 years ago but it needs batteries. I'll get some and compare the two, to see how they vary.
 
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Go through the stack and pick out some of the lightest splits. Bang them together. If they ring, like a baseball bat, they are likely dry inside. If they go thud, put them back on the stack. Try a fire with those that feel lighter and ring nicely when banged together.
 
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