BK Princess being weird

[chazcarr]

So I started up the BK princess insert this year and it is being a bit weird. I have a new Steelcat installed for this year and so far that seems to be working fine. The issue is that the stove only wants to burn half the load. I get the stove warmed up and then set the stat to 1/4 open. Last year it would cruise along at this setting for many hours no issue.
Now after a few hours at 1/4 open, I have to move to 1/2 open or else the back half of the stove wont really burn and the cat goes out.
It looks like the bypass is closing fine.
Anyone have any help on this? Never seen it before. Here is a picture of what it looks like once I move to 1/2.

 

[jetsam]

That's a partially plugged air intake/cat/flue symptom. Steelcats plug faster than ceramic. Let the stove cool off, pull the flame guard, and hit the surface of the cat with a shopvac.

Also sweep the flue and look behind the cat for a big mound of chimney sweepings.

Also turn your thermostat all the way up and all the way down, and make sure you can hear the flapper clinking open and closed.

Did you remove any flue length this year?

 

[moresnow]

Just a guess here. Are you burning wood from a different stack/age/source/specie? It can make a significant difference in your burn setting. Not to mention burning in mild weather may force a higher stat setting to accommodate lower draft. Something I have experienced recently.

 

[Highbeam]

Is it really cold yet? When it’s warmer out, the chimney doesn’t draft as hard and you need higher thermostat settings to prevent stall.

 

[chazcarr]

It is plenty cold this week. I am using Eco-blocks as my main source of wood. Could be the stealcat is clogged, I will have to check when I can. Chimney was swept last week. Nothing behind the cat as I replaced it after the sweep and inspected it to make sure I got all of the gasket bits out.

 

[jetsam]

Open and shut your thermostat and make sure you can hear the air flapper opening and closing.

1 week is pretty fast for a cat to plug, but I do know that switching wood types has given some people problems with plugging. Maybe your brand of blocks makes a lot of fly ash?

 

[begreen]

Some Princesses are known to be finicky.

Hans Christian Andersen: The Princess and the Pea

hca.gilead.org.il

 

[jetsam]

Oh yeah, definitely check to see if there is a pea underneath the hearth. That will do it every time.

 

[chazcarr]

Open and shut your thermostat and make sure you can hear the air flapper opening and closing.

1 week is pretty fast for a cat to plug, but I do know that switching wood types has given some people problems with plugging. Maybe your brand of blocks makes a lot of fly ash?

I am thinking it is something with the stat. It does not seem to open on its own as the stove cools. I have to manually move it up and down.

Any ideas how to fix that?

 

[aansorge]

I have a similar but different problem. My thermostat can sometimes stick open. Cure? A good slap on the back like she is a baby choking. Another cure: I don't open up the air all the way ever, just 3/4 open on reloads. If I do this it never sticks.

 

[Highbeam]

I have a similar but different problem. My thermostat can sometimes stick open. Cure? A good slap on the back like she is a baby choking. Another cure: I don't open up the air all the way ever, just 3/4 open on reloads. If I do this it never sticks.

I have a similar problem. My bimetallic spring just doesn’t want to overcome the slight throttle blade shaft friction to shut completely when I’m trying for low output overnight. It’s a very slight open/shut of the intake flapper that should happen. I’ve developed the habit of slapping it shut and then opening the stat to the desired cruise setting instead of just turning the star down in increments. Seems to help.

The few times I’ve had the stat cover off, I’ve cleaned and blown out the shaft pivots and applied no gum gun oil, wd40, or nothing in an effort to keep the friction low.

Sticking open is way worse! Do you have that weird third screw in the stat cover that is supposed to limit over travel of the throttle blade?

 

[jetsam]

I am thinking it is something with the stat. It does not seem to open on its own as the stove cools. I have to manually move it up and down.

Any ideas how to fix that?

@BKVP will be able to walk you through diagnosing and fixing it. (Mine has always worked fine with no maintenance.)

 

[jetsam]

I have a similar problem. My bimetallic spring just doesn’t want to overcome the slight throttle blade shaft friction to shut completely when I’m trying for low output overnight. It’s a very slight open/shut of the intake flapper that should happen. I’ve developed the habit of slapping it shut and then opening the stat to the desired cruise setting instead of just turning the star down in increments. Seems to help.

The few times I’ve had the stat cover off, I’ve cleaned and blown out the shaft pivots and applied no gum gun oil, wd40, or nothing in an effort to keep the friction low.

Sticking open is way worse! Do you have that weird third screw in the stat cover that is supposed to limit over travel of the throttle blade?

WD40 is eventually bad for low friction applications... the carrier evaporates and leaves behind machine oil, which then picks up grit and turns into chunky goo. If you've ever had a lock that felt sludgy and had one pin sticking for no apparent reason, probably somebody fixed it with WD40 in the past.

Try powdered graphite maybe? And possibly BKVP will have some better advice when he drops in.

 

[Highbeam]

WD40 is eventually bad for low friction applications... the carrier evaporates and leaves behind machine oil, which then picks up grit and turns into chunky goo. If you've ever had a lock that felt sludgy and had one pin sticking for no apparent reason, probably somebody fixed it with WD40 in the past.

Try powdered graphite maybe? And possibly BKVP will have some better advice when he drops in.

I used carburetor cleaner and compressed air last time to start from bone dry. No visible gunk of any kind was ever observed.

I wonder if the spring relaxes over time like the leaf springs on my pickup.

 

[rdust]

I have a similar problem. My bimetallic spring just doesn’t want to overcome the slight throttle blade shaft friction to shut completely when I’m trying for low output overnight. It’s a very slight open/shut of the intake flapper that should happen. I’ve developed the habit of slapping it shut and then opening the stat to the desired cruise setting instead of just turning the star down in increments. Seems to help.

The few times I’ve had the stat cover off, I’ve cleaned and blown out the shaft pivots and applied no gum gun oil, wd40, or nothing in an effort to keep the friction low.

Sticking open is way worse! Do you have that weird third screw in the stat cover that is supposed to limit over travel of the throttle blade?

Mine will stick open if I burn it on full throttle. After burning in a new load I slap it closed to make sure it’s not sticking when I turn it down. My stove is older and doesn’t have that third screw that stops the throttle blade from opening to much.

 

[chazcarr]

No screw on mine.
Another thing I noticed, when I have it choked down now, even if it cruises for awhile, the window isn't getting black anymore.
Maybe it is a bad gasket.
Dollar test shows everything seems tight.

Everything was fine until I put the metal cat in....

 

[chazcarr]

I have a similar problem. My bimetallic spring just doesn’t want to overcome the slight throttle blade shaft friction to shut completely when I’m trying for low output overnight. It’s a very slight open/shut of the intake flapper that should happen. I’ve developed the habit of slapping it shut and then opening the stat to the desired cruise setting instead of just turning the star down in increments. Seems to help.

The few times I’ve had the stat cover off, I’ve cleaned and blown out the shaft pivots and applied no gum gun oil, wd40, or nothing in an effort to keep the friction low.

Sticking open is way worse! Do you have that weird third screw in the stat cover that is supposed to limit over travel of the throttle blade?

I have noticed this too, it won't close on its own anymore either.
No 3rd screw that I am aware of.

 

[begreen]

WD40 is eventually bad for low friction applications... the carrier evaporates and leaves behind machine oil, which then picks up grit and turns into chunky goo. If you've ever had a lock that felt sludgy and had one pin sticking for no apparent reason, probably somebody fixed it with WD40 in the past.

Try powdered graphite maybe? And possibly BKVP will have some better advice when he drops in.

I would lean toward silicone spray for this application. But first, it would be good to figure out why it is sticking and make sure it is not something mechanical like a burr or something binding.

 

[Highbeam]

Silicone spray won’t evaporate into goo? It’s a cast aluminum hole with what looks like a steel shaft but could be some sort of brass. Seriously just like a regular downdraft carburetor.

Not everyone would notice the stiction. It’s when running on low and the throttle needs to just slightly open and close to maintain “idle speed”.

Rather than try to fix a problem, a better approach is just to discover a good maintenance practice for this shaft bearing surface. Carb cleaner, powdered graphite, silicone spray, etc.

I could actually witness stiction at part throttle as I slowly opened and closed the thermostat. The throttle blade would not smoothly open and close. Cleaning made the stiction go away.

 

[begreen]

In my experience silicone spray stays dry and leaves no residue at all. It won't attract dust or dirt and waterproofs, rust-proofs and lubricates. It keeps these properties over a wide range of temperatures.

 

[Highbeam]

In my experience silicone spray stays dry and leaves no residue at all. It won't attract dust or dirt and waterproofs, rust-proofs and lubricates. It keeps these properties over a wide range of temperatures.

I'm going to do it! So just regular silicon spray lubricant?

WD-40 SPECIALIST 11 oz. Specialist Silicone-300012 - The Home Depot

A multi-surface Silicone lubricant that lubricates, waterproofs and protects. WD-40 Specialist Silicone Lubricant safely lubricates, waterproofs and protects metal and non-metal surfaces such as rubber,

www.homedepot.com

The product description says the right things. Dries, invisible, will not attract dust, suitable to 500. For use on linkages, hinges, etc.

Honestly I needed silicon spray anyhow since I use it to lubricate and hydrate the rubber weather stripping and seals on my automobiles ant the slide seals on my RV.

 

[begreen]

I'm going to do it! So just regular silicon spray lubricant?

WD-40 SPECIALIST 11 oz. Specialist Silicone-300012 - The Home Depot

A multi-surface Silicone lubricant that lubricates, waterproofs and protects. WD-40 Specialist Silicone Lubricant safely lubricates, waterproofs and protects metal and non-metal surfaces such as rubber,

www.homedepot.com

The product description says the right things. Dries, invisible, will not attract dust, suitable to 500. For use on linkages, hinges, etc.

Honestly I needed silicon spray anyhow since I use it to lubricate and hydrate the rubber weather stripping and seals on my automobiles ant the slide seals on my RV.

Yes, I just buy generic, though I see now that WD-40 makes one. That should be ok as long as they don't add additives. I have been using silicone spray since the early 1970's. I had a 2 stroke Saab which had the distributer right up front. This would get wet and make the vehicle hard to start. I would spray the inside of the cap and the wires with silicone and voila, all fixed. I did this every fall. It's also great for areas you don't want residue to attract dust like the side door tracks on minivans and for sticky metal window tracks.

 

[Highbeam]

2 stroke Saab

 

[begreen]

2 stroke Saab

I had 3 of them as a young guy.

 

[chazcarr]

it is definitely the stat. It wont move on its own in either direction.