enviro EF3 adjusting exhaust fan run time

[chico]

Is there a way to adjust the run time on the exhaust
Fan ?? I find when my hopper runs dry my exhaust fan dose not stay on long enough and I get a bit of smoke coming out of my hopper

 

[SmokeyTheBear]

Yes but it will likely void the stove's certification.

Before doing the replace the low limit with an even lower limit snap disc you might want to investigate the reason the stove thinks that the hooper is an easier path for the smoke to exit than the vent system. This would likely be because of a negative pressure situation in the room with the stove or the vent system isn't as clean as it should be.

The exhaust fan runs until the low limit says the system is cool enough that it doesn't consider there to be a fire burning. Sometimes the reason why the fan takes a long time to turn on at start up and turns off early at shutdown is due to ash behind the area with the low limit switch or the snap disc not being tightly against the exhaust system where it is attached.

 

[johneh]

When was the last time you did a full clean of the stove and pipes ?
You should not get any smoke in the hopper. Also pull the hot air temp sensor and clean it .

 

[chico]

When was the last time you did a full clean of the stove and pipes ?
You should not get any smoke in the hopper. Also pull the hot air temp sensor and clean it .

the problem happened last winter ....... I am just working on the pellet stove now to get ready for this winter and I did just do a big clean out and found the exhaust vents were blocked up. I cleaned it all out and it should vent like new again now . I just allwase found the exhaust fan should stay on longer then it dose . When the stove runs out of pellets the fire gets real small wile the pellet run out of the auger and causes the heat to go below the amount to keep the fan running. So fan turns off but there is still a small amount of smaldering pelletsleft in the burn pot ........
Again the stove has now been all cleaned out for this winter but I would just like to have that fan run longer this year if the hoper runs dry so the wife doesn't give me that look if it happens again

 

[chico]

Yes but it will likely void the stove's certification.

Before doing the replace the low limit with an even lower limit snap disc you might want to investigate the reason the stove thinks that the hooper is an easier path for the smoke to exit than the vent system. This would likely be because of a negative pressure situation in the room with the stove or the vent system isn't as clean as it should be.

The exhaust fan runs until the low limit says the system is cool enough that it doesn't consider there to be a fire burning. Sometimes the reason why the fan takes a long time to turn on at start up and turns off early at shutdown is due to ash behind the area with the low limit switch or the snap disc not being tightly against the exhaust system where it is attached.

are these low limit snap discs universal ??? witch one in this link is the one to change ?
http://www.stove-parts-unlimited.co...rt=13&cat=94&show=45&page=1&f-Thermodiscs=202

 

[Don2222]

Hello

I just happen to have an Enviro EF-3 lying around. LOL

The Low Limit switch is located on the exhaust blower motor housing above the exhaust blower motor on the left side of the stove. You must unscrew the damper know and remove the upper and lower screws in front of the side door panel. Open the fire door to see them.

Remove the snap disc and see if the metal sensing bottom part is rusty or caked with ash. That will effect the operating temps.
Sometimes just cleaning that bottom can help.

See pic of the one I just replaced.

PC me with your email for more info.

Click on pics to enlarge:

 

[SmokeyTheBear]

are these low limit snap discs universal ??? witch one in this link is the one to change ?
http://www.stove-parts-unlimited.co...rt=13&cat=94&show=45&page=1&f-Thermodiscs=202

There are many close on rise snap discs you have to match the physical mounting requirements after that you can chose the on temperature and drop temperature do not go below 90 on the drop temperature or you may find the exhaust blower running in the middle of the summer. There are even adjustable ones.

 

[chico]

There are many close on rise snap discs you have to match the physical mounting requirements after that you can chose the on temperature and drop temperature do not go below 90 on the drop temperature or you may find the exhaust blower running in the middle of the summer. There are even adjustable ones.

an adjustable one would be good ...where can I find them ??

 

[SmokeyTheBear]

an adjustable one would be good ...where can I find them ??

Google is your friend as is grainger.com they have all kinds of stove related stuff.

 

[Don2222]

Hello

Those stoves also have a fan control module that frequently goes bad. If you turn the knob and the speed does not change you need a new module.

 

[Don2222]

an adjustable one would be good ...where can I find them ??

I can help you with those also.
Here are the instructions on how to PC (Private Conversation me)
https://www.hearth.com/talk/threads/how-to-respond-to-a-classified-ad.91752/

 

[MountainSean]

Hello

Those stoves also have a fan control module that frequently goes bad. If you turn the knob and the speed does not change you need a new module.

I doubt he has an issue with the control as the stove seems to be operating normally aside from turning off a little too soon which is controlled by the low limit disc more than anything else.
.
.
.
To the OP: Not all low limit discs are universal but they are fairly standard. Depending on what brand/type you get you may have to put new connections on the wires going to the snap disc. One word of warning I would give before changing that out with another one is to avoid plastic thermodiscs for the low limit position. In my personal experience they are prone to failure when used in the low limit capacity due to the constant high heat exposure.

Edited because grammar is important.

 

[webbie]

Hello

PC me with your email for price and availability.

Click on pics to enlarge:

It is against our forum policies to directly and continually solicit commercial contact with members.
Please refrain.

Any user can see the links in your signature, etc. which contain a phone number, email address, yahoo messenger, etc.

Other forums may not have rules as strict as this one, but we figure that if one person can do it, then our thousands of commercial members can also, and you can only imagine what the board would look like then,

Thanks for your understanding.

 

[Don2222]

yes sir

 

[smwilliamson]

THe stove is designed to be able to exhaust everything out WITHOUT a mod. You have to be careful here cause your stove's controls aren't digital. The low limit disc is a F140-20 switch, meaning the stove put itself in to "run" mode when the low limit disc reached and passes 140. It will close when the temp falls 20 below 140. Your stove also has an igniter. The igniter also has a switch to control it. It is a limit switch which is L120-10. At start up the ingiter is ON cause the igniter limit switch is normally closed. At 120 the switch opens and shuts off power to it. At 140 the stove is running. At shut down, whether you initiate it or the stove runs out of pellets, When the low limit switch opens at 120 power is cut to the stove...as the stove continues to cool at 110 the igniter switch closes again but because the stove if OFF the ingiter isn't powered.

Adjusting the low limit or replacing it could put your stove in a situation where the igniter is ON as the stove is trying to shut down...which could re-ignite it OR cause the low limit to stay closed from the heat of the igniter.

Now, your low limit switch might be closing prematurely...that could lead to your problems too, but so could the lack of cleaning.

 

[SmokeyTheBear]

Lack of cleaning and/or negative pressure in the room with the stove makes it hard for the smoke to exit via the vent system, instead the smoke exits via the hopper because it is the shortest resistance free path at that time.

A stove system (this includes the venting) usually needs a good cleaning more than once a year.

 

[smwilliamson]

Hello

Those stoves also have a fan control module that frequently goes bad. If you turn the knob and the speed does not change you need a new module.

that module is called a "dial-a-fire" from Enviro. Napoleon uses the same one on the NPS40. To tell of the dial a fire is bad, simply connect each lead to a DMM set to Ohms. The scale should be low to high and high to low with a nice clean sweep..if you notice the Ohms spiking or not is ascending or descending order or not moving at all during any part of the sweep...the dial a fire is bad.

 

[Don2222]

THe stove is designed to be able to exhaust everything out WITHOUT a mod. You have to be careful here cause your stove's controls aren't digital. The low limit disc is a F140-20 switch, meaning the stove put itself in to "run" mode when the low limit disc reached and passes 140. It will close when the temp falls 20 below 140. Your stove also has an igniter. The igniter also has a switch to control it. It is a limit switch which is L120-10. At start up the ingiter is ON cause the igniter limit switch is normally closed. At 120 the switch opens and shuts off power to it. At 140 the stove is running. At shut down, whether you initiate it or the stove runs out of pellets, When the low limit switch opens at 120 power is cut to the stove...as the stove continues to cool at 110 the igniter switch closes again but because the stove if OFF the ingiter isn't powered.

Adjusting the low limit or replacing it could put your stove in a situation where the igniter is ON as the stove is trying to shut down...which could re-ignite it OR cause the low limit to stay closed from the heat of the igniter.

Now, your low limit switch might be closing prematurely...that could lead to your problems too, but so could the lack of cleaning.

Very accurate, good description. The only thing to add is:
When the stove is turned off, the Blue Power Relay Module disconnects the power to the ignitor and exhaust blower. If this module is bad and the relay inside is stuck closed, the exhaust blower will keep running and the ignitor will still glow red in the burnpot after the stove is shutdown. I fixed a stove with that problem.

 

[smwilliamson]

Very accurate, good description. The only thing to add is:
When the stove is turned off, the Blue Power Relay Module disconnects the power to the ignitor and exhaust blower. If this module is bad and the relay inside is stuck closed, the exhaust blower will keep running and the ignitor will still glow red in the burnpot after the stove is shutdown. I fixed a stove with that problem.

the proof of fire switch by-passes the start timer relay, the starter relay box cuts power to EVERYTHING except the room blower. sometimes people reverse the wires on the startup timer too and the box is still good

 

[Don2222]

Also if there were a glass fuse in the Napoleon, then every time the ignitor died and shorted out, the house fuse or circuit breaker would not trip! LOL

 

[chico]

Is there a way to adjust the run time on the exhaust
Fan ?? I find when my hopper runs dry my exhaust fan dose not stay on long enough and I get a bit of smoke coming out of my hopper

I noticed some other pellet stoves have a seal on the hopper lid ...... Mine dose not as it was not made with one . would it be OK for me to put a seal around the hopper lid ??? Or would that have some kind of bad affect on how the stove operates ?

 

[smwilliamson]

I noticed some other pellet stoves have a seal on the hopper lid ...... Mine dose not as it was not made with one . would it be OK for me to put a seal around the hopper lid ??? Or would that have some kind of bad affect on how the stove operates ?

the unit should be safe to run as is, anything else is an experiment with fire in your home. Your call.

 

[chrisasst]

My EF2 does the same thing. Guess I will have to reread this thread for some info.

 

[chico]

THe stove is designed to be able to exhaust everything out WITHOUT a mod. You have to be careful here cause your stove's controls aren't digital. The low limit disc is a F140-20 switch, meaning the stove put itself in to "run" mode when the low limit disc reached and passes 140. It will close when the temp falls 20 below 140. Your stove also has an igniter. The igniter also has a switch to control it. It is a limit switch hich is L120-10. At start up the ingiter is ON cause the igniter limit switch is normally closed. At 120 the switch opens and shuts off power to it. At 140 the stove is running. At shut down, whether you initiate it or the stove runs out of pellets, When the low limit switch opens at 120 power is cut to the stove...as the stove continues to cool at 110 the igniter switch closes again but because the stove if OFF the ingiter isn't powered.

Adjusting the low limit or replacing it could put your stove in a situation where the igniter is ON as the stove is trying to shut down...which could re-ignite it OR cause the low limit to stay closed from the heat of the igniter.

Now, your low limit switch might be closing prematurely...that could lead to your problems too, but so could the lack of cleaning.

Ok so I put the stove back in last night after my deep clean and did a test run...... The stove is running like a champ ! nice flame and running the best it has in years. But still seams to be a problem with low limit disk. when I turn the stove off the exhaust fan stops early. I checked the temp at the exhaust ( right beside the low limit disk) and the fan is turning off at 180 F . So as soon as the stove cools down I will take it out to check for damage to the switch. right now it looks like it is not working right

 

[SmokeyTheBear]

Ok so I put the stove back in last night after my deep clean and did a test run...... The stove is running like a champ ! nice flame and running the best it has in years. But still seams to be a problem with low limit disk. when I turn the stove off the exhaust fan stops early. I checked the temp at the exhaust ( right beside the low limit disk) and the fan is turning off at 180 F . So as soon as the stove cools down I will take it out to check for damage to the switch. right now it looks like it is not working right

When you did your cleaning did you clean the area behind where the low limit is mounted as well as the switch itself and make certain that the switch is against the exhaust manifold or is fully seated in the exhaust air flow (if this is where it goes on the EF3) ?

This in addition to a faulty (worn out) switch can cause it to not function at the proper temperature.