Serenity - Thermostat functionality

[Talegas]

I feel I have been poking your brains way too much, but as another forum member stated, this is actually fun!

The topic of today's thread is: what the heck does the thermostat do?

My understanding is the following:
1. The serenity has multiple stalls which each of them represents a group of settings to control the BTUs in one way or another
2. The different settings these stalls controls are: a. auger speed, b. exhaust fan speed, c. room fan speed
3. ASSUMPTION: auger speed is already defined and fixed for each stall level
4. only settings that you can modify (linked to each of the stalls) are the speed of fans (blowers)

That said, is the thermostat only there to pick and choose the stall to which the stove will run depending on the temperature set by the end user?

If the answer is yes, then why in the world would a bag of pellets last longer with the thermostat (automatic setting) being used than when using the manual setting WHILE BOTH are on Stall1?

It makes me wonder if thermostat would also control auger speed a bit more granular than the fixed stall speed in manual.

Thoughts? (I'll be reading the manual now that I am typing this to see if the answer lies there)

update: The manual states and I quote:
"In thermostat mode, the stove will not go into standby. It will simple idle and continue to produce a fire until the room is no longer at the set 'call to' temperature. When is idling, the stove will read at power level one in the power level box on the display screen."

WTF does that mean?! Does it mean that "idle" is a setting that is not power level 1 (stall1)? does it mean that in fact it does have a hidden setting that changes the auger speed?
Cheers!

 

[Deezl Smoke]

I feel I have been poking your brains way too much, but as another forum member stated, this is actually fun!

The topic of today's thread is: what the heck does the thermostat do?

My understanding is the following:
1. The serenity has multiple stalls which each of them represents a group of settings to control the BTUs in one way or another
2. The different settings these stalls controls are: a. auger speed, b. exhaust fan speed, c. room fan speed
3. ASSUMPTION: auger speed is already defined and fixed for each stall level
4. only settings that you can modify (linked to each of the stalls) are the speed of fans (blowers)

That said, is the thermostat only there to pick and choose the stall to which the stove will run depending on the temperature set by the end user?

If the answer is yes, then why in the world would a bag of pellets last longer with the thermostat (automatic setting) being used than when using the manual setting WHILE BOTH are on Stall1?

It makes me wonder if thermostat would also control auger speed a bit more granular than the fixed stall speed in manual.

Thoughts? (I'll be reading the manual now that I am typing this to see if the answer lies there)

Cheers!

I really cant answer anything directly about the thermostat as I have not looked into it since I do not plan to use it.

That said, the remote thermostat runs the stove based on air temperature at the thermostat location. Manual heat settings in the control panel run the stove based on your input and the only temperature influence is for safety shut down in case of over temp or under temp. So even though the lowest settings are chosen on manual, they may not be as low as a remote thermostat can run the stove. Manual settings have to have an upper and lower limit to keep the control panel simple to use and to keep the stove's usage within a known to be reliable range. The factory most likely runs long duration tests to find what low manual settings can be input by the consumer and still function without the fire going out on low, or the stove burning up on high.

If you turn over control to a tested remote thermostat, then if it is installed with in the guide lines set up in the manuals of the thermostat and stove, it may be possible to control pellet feed rate and blower speeds beyond the manual limits without the fire going out or the stove burning up. But I have read where some stoves of other brands that are run by remote thermostat will actually shut down and restart as needed to retain temperature in the house. That may explain the lower pellet usage? But it may also explain shorter igniter replacement intervals.

 

[johneh]

Auger speed does not change ( most auger motors are rated at 1 RPM )
Auger timing changes the higher the call for heat the more often the auger turns
to supply more pellets for more heat . At level 1 or idle the stove is operating
at the lowest point that a fire can be maintained without going out . That is why
less pellets are used on at stat if it spend more time idling than in heat call .
I hope this all makes sense.

 

[Talegas]

One thing, I am not referring to a remote thermostat. The Serenity has a "stove thermostat" which is the one set as "call to" temperature. This is the one that is met and then it goes into "idle" mode which, I BET and will test today, lowers the speed of the auger.

I am almost positive on that now since the current temperature of the stove is 83 at stall 1 while the temp on "stall1" (more like idle) was 76.

 

[Talegas]

Auger speed does not change ( most auger motors are rated at 1 RPM )
Auger timing changes the higher the call for heat the more often the auger turns
to supply more pellets for more heat . At level 1 or idle the stove is operating
at the lowest point that a fire can be maintained without going out . That is why
less pellets are used on at stat if it spend more time idling than in heat call .
I hope this all makes sense.

So staying away from how the motor goes at a constant speed while the auger is variable due to other mechanisms, I think level 1 (stall1) is not the same as idle. So yes, i am right now believing that idle (which is a mode only available with thermostat mode) is the lowest feed rate for the auger.

 

[Talegas]

Wow, I am learning more stuff about my stove every day.

I am able to change settings while the stove is in the shutdown mode, once settings are changed i can press the ON button again, but sadly it waits for the shutdown to complete before re-starting the fire.

I would have assumed it was a better design to re-ignite while the stove is warmer to be more efficient.

 

[johneh]

The auger is mounted on the auger motor look at the parts listing and blow up
The motor is a 1rpm electric motor . it is controlled by the board it is an on/off
control the board may have infinite settings but there is no change to auger operation or
mechanics it is on or off . The pitch of the blades is not variable to deliver more or less pellets
It is just the speed that they are delivered is changed . Pellet motor on longer !

 

[Deezl Smoke]

Wow, I am learning more stuff about my stove every day.

I am able to change settings while the stove is in the shutdown mode, once settings are changed i can press the ON button again, but sadly it waits for the shutdown to complete before re-starting the fire.

I would have assumed it was a better design to re-ignite while the stove is warmer to be more efficient.

Part of the Serenity's appeal is it's simplicity. I bet it would take a more complex and expensive control panel.

 

[Talegas]

The auger is mounted on the auger motor look at the parts listing and blow up
The motor is a 1rpm electric motor . it is controlled by the board it is an on/off
control the board may have infinite settings but there is no change to auger operation or
mechanics it is on or off . The pitch of the blades is not variable to deliver more or less pellets
It is just the speed that they are delivered is changed . Pellet motor on longer !

ok ok,. i got it already
let's call it "feed rate".

 

[rich2500]

My Ravelli works the same way in that once you hit the off button even if you hit start while the stove is shutting down the stove needs to go through the complete shutdown cycle and then it will automatically restart.Also my Ravelli has a modulation mode in which once the stove reaches the set thermostat temp.it drops into modulation mode. My best guess is that the Serenity does the same thing.

 

[Talegas]

My Ravelli works the same way in that once you hit the off button even if you hit start while the stove is shutting down the stove needs to go through the complete shutdown cycle and then it will automatically restart.Also my Ravelli has a modulation mode in which once the stove reaches the set thermostat temp.it drops into modulation mode. My best guess is that the Serenity does the same thing.

That is exactly what I am testing right now. The "idle" mode the manual states it goes into once the "call to" temp has been reached. I am assuming that in the idle state, the feed rate of pellets drops below the rate set for manual on the lowest stall.

The way i am testing is that it should last the whole 24hrs just like the other pellets were lasting.. with the HUGE caveat that this new bags of lignetics are freaking BURNING .. and i mean BURNING. NAP had to sometimes burn in high to keep up with the call to temp, while Blackstone seldom needed it as it was higher than 3 degrees than the call to temp.. .this bad boys are keeping the temp 7 degrees above the call to temp and hasn't had the need to jump to stall 5 at all.

 

[Talegas]

Part of the Serenity's appeal is it's simplicity. I bet it would take a more complex and expensive control panel.

Interesting!

I'll google up or even ask Ardisam if there are any specs to look for (interface wise) so i can use a "better" control panel.