Well the last week has seen us use the new to us stove every night and it has done a marvelous job at keeping the place warm.
Now, that said the controls on the stove have some issues.
The blower fan has basically one stable speed and one area on the dial that it will hunt up and down.
The steady speed is a good one and is not too noisy and puts out a good amount of airflow.
OK I am sure that the control board is tired as this is a 93 model stove.
SOOOOOOOOOOO
I am going to set up a Mosfet solid state relay that has on and off times adjustable
With this relay I will install a "one shot" relay that is also adjustable to feed power aqround the low temp snap switch during startup.
OK the timing is easy, the fan speed is no biggy either, I am using an adjustable POT to permanently set the fan speed to what I desire.
The exhaust blower will be set to the optimal speed using a similar POT as used for the room air fan.
I have a strobe tach and have already checked the speeds on the room air fan and the exhaust blower while running.
I really dont like the particular overtemp safety snap discs and am going to replace them with the same temp range but instead use the manual reset type.
So if the stove overheats the snap disc will open and then need to be manually reset to apply power.
Really dont want the thing coming back to life if there were an issue.
Done some draft tests the other day with a borrowed magnahelic guage and the firebox depression is right in the sweet spot.
So the fuel rates will be Auger on for 1.4 seconds (Relay is adjustable so the optimal auger on time can be set and locked in) Factory setting is 1.4 but from 1.3 to 2 is the window.
The Burn time or off times will be adjustable from 2.5 seconds (High heat) to 6 seconds (low heat)
The exhaust fan voltage is supposed to change with the fuel settings but does not.
I am going to use the current fan speed as it works great with the settings I need.
The relays use 8 pin and 11 pin plug in architecture so all set there.
The original control panel location is perfect. I have a new panel blank made up and will install all switches and controls in the new panel.
I am also installing a master FUSE receptacle in the panel as well as a master power switch.
I am going to use a fixed room air fan speed with a switch to turn the fan off while starting the stove.
The fan circuit will have an added snap switch that will turn the fan off if someone fails to turn the fan on thus preventing an overtemp situation.
Earth Stove did this. The fan was on a Rheostat and if you did not turn it on, the snap switch would pop the fan on high every so offten to keep the stove temps in check.
I need to clean the firepot on the fly using the nut shells and not being able to turn off the room air blower is ugly when you pop the door open to clear the clinkers. (ash blows all over)
I also want to install a pressure switch on the firebox that will shut the stove off if the door should pop open or be left open.
This stove model has a pressure switch on the exhaust side to shut it off if the exhaust is plugged but no doo ajar safety.
I may also wire in a stack temp snap switch that will shut things off if the stack reaches 250F at the point where it goes into the thimble.
These pipes get hot, to the point that placing ones hand on it will get your attention
This will be summers project. Actually really simple to do and I have most of the stuff needed already.
The analog controls used in these oder stove had many issues and the replacment digital boards are just expensive and still problematic.
The main controls I am using are off the shelf technology and readily available for very little $$$$
Less than $100 for both relays the adjustment pots and the sockets to hold the relays.
The rated cycles of these relays are in the multi millions and the manufacture told me that short of abuse they have never had any real issues.
The Mosfet solid state relays are industrial strength and the style Ihave are rated for 120V at 10 amps
Looking forward to a simple and reliable contoller for the Old girl.
The plan may seem a little lacking in control but for what I use my stove for, one or two heat settings is all I need with the nut shell based fuel
As all this comes together I will snap piccy's and do a schematic of the install and post it here.
The company I am getting the relays from used to supply almost all pellet stove makers with these type controls.
This stopped when the manufactures went to all proprietary controls and had the stuff made overseas.
This was a big cost saving measure and not one to make the stoves any better.
The digital control boards are not very forgiving of a shorted motor (fan or ??) and one good power hit during a storm can trash a $300 control board POOOOOOF.
The relays are far more forgiving.
Nice thing is that if a relay fails its 5 minutes, start to finish to swap in a new one and be back running. Actually on this stove the side panel could be opened, the relay unplugged and a new one installed without dropping the fire.
Just unplug the stove for a few minutes, do the swap and repower and right back at it.
The greatest issue with the control boards is the integrity of the components or lack there of.
Far too complex for something as simple as a fire.
The major parts such as the auger motor and the fan motors (Exhaust and room air fan) are tough items that can last for a buttload of years even being used every season 24/7 as long as they are serviced regularly.
The physical parts of the stove (firebox, pot and cabinet) should be able to last for 20-30 years or longer.
Keep an eye out and I will make sure to post stuff on this redo.
Snowy
Now, that said the controls on the stove have some issues.
The blower fan has basically one stable speed and one area on the dial that it will hunt up and down.
The steady speed is a good one and is not too noisy and puts out a good amount of airflow.
OK I am sure that the control board is tired as this is a 93 model stove.
SOOOOOOOOOOO
I am going to set up a Mosfet solid state relay that has on and off times adjustable
With this relay I will install a "one shot" relay that is also adjustable to feed power aqround the low temp snap switch during startup.
OK the timing is easy, the fan speed is no biggy either, I am using an adjustable POT to permanently set the fan speed to what I desire.
The exhaust blower will be set to the optimal speed using a similar POT as used for the room air fan.
I have a strobe tach and have already checked the speeds on the room air fan and the exhaust blower while running.
I really dont like the particular overtemp safety snap discs and am going to replace them with the same temp range but instead use the manual reset type.
So if the stove overheats the snap disc will open and then need to be manually reset to apply power.
Really dont want the thing coming back to life if there were an issue.
Done some draft tests the other day with a borrowed magnahelic guage and the firebox depression is right in the sweet spot.
So the fuel rates will be Auger on for 1.4 seconds (Relay is adjustable so the optimal auger on time can be set and locked in) Factory setting is 1.4 but from 1.3 to 2 is the window.
The Burn time or off times will be adjustable from 2.5 seconds (High heat) to 6 seconds (low heat)
The exhaust fan voltage is supposed to change with the fuel settings but does not.
I am going to use the current fan speed as it works great with the settings I need.
The relays use 8 pin and 11 pin plug in architecture so all set there.
The original control panel location is perfect. I have a new panel blank made up and will install all switches and controls in the new panel.
I am also installing a master FUSE receptacle in the panel as well as a master power switch.
I am going to use a fixed room air fan speed with a switch to turn the fan off while starting the stove.
The fan circuit will have an added snap switch that will turn the fan off if someone fails to turn the fan on thus preventing an overtemp situation.
Earth Stove did this. The fan was on a Rheostat and if you did not turn it on, the snap switch would pop the fan on high every so offten to keep the stove temps in check.
I need to clean the firepot on the fly using the nut shells and not being able to turn off the room air blower is ugly when you pop the door open to clear the clinkers. (ash blows all over)
I also want to install a pressure switch on the firebox that will shut the stove off if the door should pop open or be left open.
This stove model has a pressure switch on the exhaust side to shut it off if the exhaust is plugged but no doo ajar safety.
I may also wire in a stack temp snap switch that will shut things off if the stack reaches 250F at the point where it goes into the thimble.
These pipes get hot, to the point that placing ones hand on it will get your attention
This will be summers project. Actually really simple to do and I have most of the stuff needed already.
The analog controls used in these oder stove had many issues and the replacment digital boards are just expensive and still problematic.
The main controls I am using are off the shelf technology and readily available for very little $$$$
Less than $100 for both relays the adjustment pots and the sockets to hold the relays.
The rated cycles of these relays are in the multi millions and the manufacture told me that short of abuse they have never had any real issues.
The Mosfet solid state relays are industrial strength and the style Ihave are rated for 120V at 10 amps
Looking forward to a simple and reliable contoller for the Old girl.
The plan may seem a little lacking in control but for what I use my stove for, one or two heat settings is all I need with the nut shell based fuel
As all this comes together I will snap piccy's and do a schematic of the install and post it here.
The company I am getting the relays from used to supply almost all pellet stove makers with these type controls.
This stopped when the manufactures went to all proprietary controls and had the stuff made overseas.
This was a big cost saving measure and not one to make the stoves any better.
The digital control boards are not very forgiving of a shorted motor (fan or ??) and one good power hit during a storm can trash a $300 control board POOOOOOF.
The relays are far more forgiving.
Nice thing is that if a relay fails its 5 minutes, start to finish to swap in a new one and be back running. Actually on this stove the side panel could be opened, the relay unplugged and a new one installed without dropping the fire.
Just unplug the stove for a few minutes, do the swap and repower and right back at it.
The greatest issue with the control boards is the integrity of the components or lack there of.
Far too complex for something as simple as a fire.
The major parts such as the auger motor and the fan motors (Exhaust and room air fan) are tough items that can last for a buttload of years even being used every season 24/7 as long as they are serviced regularly.
The physical parts of the stove (firebox, pot and cabinet) should be able to last for 20-30 years or longer.
Keep an eye out and I will make sure to post stuff on this redo.
Snowy
