Lopi snap disk "turn on" temp

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clutch25

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Feb 3, 2009
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Does anyone know the "turn on" temp for the Lopi snap disk fan switch by chance? Just got the stove in (pics to follow next week in new thread) and had a break in fire to cook the paint. I got the stove what I considered plenty hot enough to turn on the fan but it never did activate.

I checked the fan and the motors are good and it will blow with the switch jumped.

Notes:

Used Lopi Republic 1750.

Thanks!
 
Usually is say the close temp and differential on the side of the switch in fine print. It will be something like 125-30. Check to be sure that the switch is making good contact with the stove body. If there is a spring steel plate holding the switch, bend it a bit to put more pressure on the switch against the stove.
 
clutch25 said:
Does anyone know the "turn on" temp for the Lopi snap disk fan switch by chance? Just got the stove in (pics to follow next week in new thread) and had a break in fire to cook the paint. I got the stove what I considered plenty hot enough to turn on the fan but it never did activate.

I checked the fan and the motors are good and it will blow with the switch jumped.

Notes:

Used Lopi Republic 1750.

Thanks!


We have the Liberty with the fan, could take 20-30 minutes.



zap
 
Thanks!

I checked the pressure of the switch last night and it felt pretty tight in the mounting. I will check it again tonight. Still pretty warm out to have a roaring fire going in the house even with all the windows open...

Picking up a new stove top thermometer this afternoon so I can be a little more specific in the facts reported.
 
you will most likely need more then a small break in or knidling fire to get the blower on
 
I haven't looked into the HOW, but I'll say that I've wanted to modify my fan. I can have the stove top at 450-500 and the fan still isn't on. 20-30 minutes is normal. Lotta heat not yet getting pumped out.

If anything, I'd want mine to come on and stay on when the stove top is at 200 degrees. Which usually is about 5-7 minutes after a cold start.
 
clutch25 said:
Does anyone know the "turn on" temp for the Lopi snap disk fan switch by chance? Just got the stove in (pics to follow next week in new thread) and had a break in fire to cook the paint. I got the stove what I considered plenty hot enough to turn on the fan but it never did activate.

I checked the fan and the motors are good and it will blow with the switch jumped.

Notes:

Used Lopi Republic 1750.

Thanks!


Once you get burning 24/7 forget about the 20/30 minutes, you'll need to turn it down! :zip:


zap
 
On my Endeavor from a cold start it can take 45 minutes to 1 hour and stove top around 600. There have been times when I thought it was never going to turn on and the stove was getting near 700. I wanted to turn the blower on to cool of the stove. It usually clicks on when I'm just starting to feel a little panic. :lol: When I'm burning 24/7 the fan is much more consistent.

The switch location on the endeavor is at the top on the back so it take a while to get the steel cooking that far up the back.
 
joefrompa said:
I haven't looked into the HOW, but I'll say that I've wanted to modify my fan. I can have the stove top at 450-500 and the fan still isn't on. 20-30 minutes is normal. Lotta heat not yet getting pumped out.

If anything, I'd want mine to come on and stay on when the stove top is at 200 degrees. Which usually is about 5-7 minutes after a cold start.

Joe, its all about condensing and getting a clean burn. They want to get rid of all those cooler areas 1st to help with complete combustion. Running the fan too early will interfere with this process. A blower puts a fair load on the unit. Its amazing how it will affect the burn time on my stove.
 
rdust said:
On my Endeavor from a cold start it can take 45 minutes to 1 hour and stove top around 600. There have been times when I thought it was never going to turn on and the stove was getting near 700. I wanted to turn the blower on to cool of the stove. It usually clicks on when I'm just starting to feel a little panic. :lol: When I'm burning 24/7 the fan is much more consistent.

The switch location on the endeavor is at the top on the back so it take a while to get the steel cooking that far up the back.

The guys who installed my stove installed my temp sensor incorrectly on the bottom of the stove where the convective air is sucked in, not correctly between the rear heat shield and the stove (like I did). The directions were misleading IMO. I too can have my stove up to 600 or more degrees before my blower will kick on.

Anyhow, the installers did tell me if I cut the two wires to the temp sensor and spliced them together, I would have manual control over the blower unit. If my temp sensor ever goes out and the fan unit still works, I may do that.
 
north of 60 said:
joefrompa said:
I haven't looked into the HOW, but I'll say that I've wanted to modify my fan. I can have the stove top at 450-500 and the fan still isn't on. 20-30 minutes is normal. Lotta heat not yet getting pumped out.

If anything, I'd want mine to come on and stay on when the stove top is at 200 degrees. Which usually is about 5-7 minutes after a cold start.

Joe, its all about condensing and getting a clean burn. They want to get rid of all those cooler areas 1st to help with complete combustion. Running the fan too early will interfere with this process. A blower puts a fair load on the unit. Its amazing how it will affect the burn time on my stove.

I've observed that too - when my blower is really going, the stove works very differently than when it's off.

That being said, I've been around another plate steel stove and cast iron stove (Vogelzang and Jotul) whose fan's kick on FAR earlier and provide meaningful heat that much faster, without seeming to suffer any ill effects.

Is there anything I can do to make my fan kick on sooner/stay on longer as the stove cools down?
 
Update and some info...

I reached into the air intake and poked the snap disk again tonight.

Got a fire going tonight, had a tough time getting it moving due to using some wood shop scraps that probably weren't as dry as they should be. It still only took me about 20 minutes to get the whole thing up to temp with a crappy draft and poor wood. Anyway, got the stove going and plugged in the blower and it kicked on right away. I bought a new Rutland stove top thermometer and it was showing around 450 I believe. The temp reads high on it by about 50 degrees at room temp and them I'm pretty sure it reads low at upper scale readings. Either way it is just a reference and I plan to bring down some lab thermometers and get a laser temp gauge also in the future.

So, on slab wood drops, and wood working scraps, the fan has been running about 2 hours non stop, every window in the house is open and it is around 86 by the stove....

Might have finally got it to go out now with the draft shut completely for the last 20 minutes. Stove got to almost 550 on the top before I realized that I need to move the therm. to the middle of the stove and out of the fan draft. I probably had a good 650 or better on the stove top.

Anyway, a person could put the fan on manual control for probably about $2 and 10 minutes worth of work. NOT THAT I RECOMMEND IT (disclaimer)! The fan switch is a "normally open" low amperage switch, that's as far as I'm going with it....

Pics to follow on Monday....
 
I'd say 600 or 650 is a common "cruising" temp on my stove. It is interesting how much more intense 750 or 775 is IMO. If your stove is ever getting to warm you can turn that fan up to high and it will drop the temp some.

After my usual digression, back to your regularly scheduled thread.
 
I have the fireplace extrodinaire / lopi declaration. The snap disk is mounted on the bottom right of the firebox. It would require the fireplace to hit the same temperature as the surface of the sun before it clicked on. No joke, it was no uncommon for the first load of wood to be consumed before it turned on... terrible.

It was super easy to bypass though, cut the wires and connect them. Now I turn it on and off as I see fit. It gets turned on at about 30-45 min (maybe a bit early) then runs full power until the fire is out. I get the most heat out that way. After 3 years of doing this I can also say that it is not producing any more creosote then before.

Rick
 
Mine often consumes the first load of wood (assuming the first load gets 5 minutes with the door cracked and then most of the rest with a good amount of air flowing through). Before the fan turns on.

Are there articles anywhere on how to modify it to come on at a lower temperature? I still want it automated - I want it to turn itself off - but I just want it to come on far earlier.

I will say that I can put a load of wood on a roaring 600 degree fire, get roiling secondaries from the new wood instantly, and by turning the fan all the way up the stove won't do more than crack 700. The fan, on high, is absolutely amazing at controlling the stove's heat.
 
MarkinNC said:
rdust said:
On my Endeavor from a cold start it can take 45 minutes to 1 hour and stove top around 600. There have been times when I thought it was never going to turn on and the stove was getting near 700. I wanted to turn the blower on to cool of the stove. It usually clicks on when I'm just starting to feel a little panic. :lol: When I'm burning 24/7 the fan is much more consistent.

The switch location on the endeavor is at the top on the back so it take a while to get the steel cooking that far up the back.

The guys who installed my stove installed my temp sensor incorrectly on the bottom of the stove where the convective air is sucked in, not correctly between the rear heat shield and the stove (like I did). The directions were misleading IMO. I too can have my stove up to 600 or more degrees before my blower will kick on.

Anyhow, the installers did tell me if I cut the two wires to the temp sensor and spliced them together, I would have manual control over the blower unit. If my temp sensor ever goes out and the fan unit still works, I may do that.


the switch is a $12 part. I wouldnt recomend using it with out this part
 
yep, very cheap to get on grainger, or probably amazon. Just have to try a few temperatures until you get one that you are happy with, if you choose to go that route.
 
I'm still watching and learning from this thread. But I wanted to hijack (sidetrack?) to ask a question:

I talked with my installer and told him I wanted the fan to run most of the time in order to make the fire more efficient. He said, "You know, the fan just barely kicks up the efficiency. Cool air will come in the bottom and be warmed and leave the top through convection even if you don't run the fan. The difference in efficiency is negligible."

I have a hard time believing this and would welcome any commentary.

By the way, painting the device black will only have a difference if it is being heated through radiant visible light. Visible light is absorbed by black and reflected by white, so if you have sunlight shining on something, black will get hotter quicker. But inside a stove where there is no visible light there is no difference. My $0.02.

Sam
 
samhoff2 said:
I'm still watching and learning from this thread. But I wanted to hijack (sidetrack?) to ask a question:

I talked with my installer and told him I wanted the fan to run most of the time in order to make the fire more efficient. He said, "You know, the fan just barely kicks up the efficiency. Cool air will come in the bottom and be warmed and leave the top through convection even if you don't run the fan. The difference in efficiency is negligible."

I have a hard time believing this and would welcome any commentary.

By the way, painting the device black will only have a difference if it is being heated through radiant visible light. Visible light is absorbed by black and reflected by white, so if you have sunlight shining on something, black will get hotter quicker. But inside a stove where there is no visible light there is no difference. My $0.02.

Sam

The visable light thing, I had the same thought but you articulated it well. Imo blowers do not increase effecancy as they do not creat more heat they just push it farther into the room and help spread the heat around
 
samhoff2 said:
I wanted the fan to run most of the time in order to make the fire more efficient.

There have been a few seperate threads on this topic. In short, if it is a stand along unit, the fan helps a little. if it is a insert, the fan is mandatory. I have lost power before, the fireplace barely puts out any heatwithout the fan. Do your own test, see how your fireplace heats the house without the fan, each model is different. Its virtually mandatory for mine. This is why I want the fan to run non stop and on full power. This is why I bypassed the snap disk, one of the best decisions I have made! haha
 
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