Ashford 25 thermostat calibration

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New Member
Dec 8, 2023
Could have a major issue or nothing at all. New Ashford 25. Lights fine, I let it get hot, it gets into active zone, I let it go a bit longer, I turn it down, it's good for ~2-2.5hrs but drops to inactive, but it continues for many hours, even overnight with good heat and no smoke inside or out. I ran the cat combuster test 3 times per the manual and it was good. The thermostat up/down and bypass seem to function just fine. Cat looks clean when red. Thermostat is low/medium and same with the blower. It looks like the thermostat may need to be calibrated as everything seems to work great but the manual clearly says the cat should be active when burning at all times, although there is a contradictory section with instructions on how to reload if the needle falls below active on the cat. I tried to contact blazeking but it's just email and I guessing they may just point me to the installer. I think it's working but the gauge may be off.

I did have a few issues with the first installer (third party) but the dealer came out in-person to do the job correctly. However, they did not run a test load of wood. Not sure if that's standard or not.

Any info would be appreciated as I have no other source of heat as I'm replacing my hydronic baseboards with radiators and it's very cold the next few weeks. I really have no choice but to continue to run this. I had sticker shock when I first bought this but assumed it would pay for itself in time - I'm just not sure if I'm damaging the unit or if it's working just fine. If not for the ink, I'd use the manual to start my next fire - I've learned more from this form.
And to add to this. When it gets close or below inactive, I open the thermostat all the way in the hopes to get it back up or just burn down whatever is left in the stove. I may be operating this way above what it should be. Again, great heat, long burn, but no idea if I'm doing damage.
It’s not normal for the installer to sit there and enjoy burning a whole load of fuel. Could take two full days on some models!

If I was you I would run it. Monitor the flue emissions to be sure you haven’t stalled the cat. Maybe not flirt with the minimum output settings until you get this sorted out.
Thanks. Fair point for the installer - makes sense. When the cat bypass is closed there is 0 smoke out the flu which leads to me to believe everything is working fine but perhaps the cat on/off was reading activity consistently.
Update. It's getting better. I got 5+ hrs int the active zone. Pulling coals forward and nearly a full load. Larger wood seems to help. I've been advised to really push the wood in the back, us large pieces, and fill it 100%. I'll be trying this tonight. This technique + adjusting the blower and thermost will hopefully increase the burn time the in active state. I'm still not so sure the on/off cat gauge is accurate - seems very efficient when it's in the grey/inactive state. I think it just shows when the cat is 500 degrees or more and it's a needle vs. a true on/off - perhaps it's not the most accurate gauge to begin with and more just to get the fire started and bypass closed to engage the cat.
Even an on/off gauge should be calibrated to stay on anytime the cat is above 500. I would expect that dang thing to be “on” the majority of the burn season.
I'd think so, but it goes inactive 5 hrs in. I suppose I could do a refill but it's plenty hot and kicking out a ton of heat. Plus that would be a lot of wood per day and defeat the point of a high efficiency stove. I'm going to keep experimenting with each cycle. Everything seems good and I am getting the "angle wing" pattern of slight build up which suggests the cat is work as it should.
The wood is pretty burned down when it goes inactive but it's still there - more small chunks in a large ash pile. I'm going to try the slower front to back burn method. I'm also getting a lot of creosote build-up on the glass. Apparently this is normal. I cleaned it and will observe the patter. I was getting the "angle wing" patter which apparently is an indicator the cat is working as it should. My manual says wood should be 12-18% but I've heard < 15% is best. When I did get the longer burn, I used some select oak when I had a good burn in the active zone. I have a lot of wood on my property that was left and it's been more than a year but I may have to try another select batch or just break down and buy a small very dry load and give it a test - it may be the wood after all. I also keep the wood outside and it's more wet on the outside. I have a load drying on the radiators which may seem to help.
I did find a gap in the loading door just above where the handle latches. I adjusted the tension and it's now tight. There was 0 resistance when I did a paper test. I also cleaned out the coals and removed the bottom grate to clean and vacuum. I just did a cold start and ensured it burned hot for 30-mins before reducing the thermostat. So far so good. Looks to be burning much slow. I also noticed if I turn the thermostat all the way down the fire goes out. This was not the case would just burn slow - this may have been a result of the gap that's not be remediated.
Update. While the gap was likely a small problem and I'm glad I found it, the culprit turned out to be the wood. I bought some good seasoned ash and I've been burning at the lowest setting with the blower off for the last 6 hrs and the cat is active with no visible fire, just red/orange base glow and I still have nearly a full load of wood. I cut fresh oak this year but when I bought the property there was oak already chopped and that was a year ago. Oak needs longer to season plus a good bit of it was damaged by carpenter ants - some felt a bit light and hallow for oak. It tested dry when split but it was probably setting uncovered for too long and had some dry rot. I should be good for several hrs now. I'd like to see how long a burn I can get while the cat is active - it's rated for 25 hrs (Ashford 25) with perfect wood/conditions....I'd be happy with 15-20. While I'm going to have to buy wood this year, which hurts, one load a day or so should still be cost effective. Thanks for all the feedback on this issue. I came full circle, thinking it could not have been the wood and that should have been the first thing I tired.
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You can get a good impression on the fuel left when you stir it a little with a poker. Don't let volume fool you, it's mass that counts.
So if you have loosely split-shaped, charred hunks that are very, very light, not much fuel remains. So it's not surprising your cat drops out of active. The tank is just empty.

I mostly burn pine (that's what we have in our woods) and I also try to only take already dead trees. That means that if I don't catch it early enough, it already has some wood loss to insects. Some splits were light as balsa wood after drying. Those burn well, but obviously don't contain much energy, resulting in low burn times.