Reading Allegheny temp overshoot

Reading Allegheny temp overshoot

PostBy: satza On: Sun Apr 01, 2012 10:51 pm

I recently purchased a Reading Allegheny with the coaltrol system. I have the stove dialed in, i think With a min-3 max-25 cft-8. I have the day setback at 63 and the night setback on 75. The problem i am having is when it switches from day to night and ramps up to warm the house up, it takes forever to ramp back down and the house ends up being 80 plus degrees by the time it returns to idle. I was wondering if there was another setting i am missing or if my setbacks are just too far apart?
satza
 
Stove/Furnace Make: Reading
Stove/Furnace Model: Allegheny

Re: Reading Allegheny temp overshoot

PostBy: plumb-r On: Mon Apr 02, 2012 6:37 am

Welcome to the forum, I have a Hitzer stoker with coal-trol. Diffrent but the same as yours. One of the first things I learned is everything happens slow with coal. Heats up slow ,cools off slow.I found anything more than a 2degree set back or up caused overshoot or undershoot. It takes some time for the stove to get cranked up to max feed rate to bring your set up temp up 10 degrees, it's still at max feed rate when you get to your set temp. Then it takes time for the stove to come back to normal causeing the overshoot. Other things can effect overshoot like house construction, insulation, t-stat location. Yours sounds like you have just to much of a diffrence between set temps. It's not a hot air furnace and will not act like one. :)
plumb-r
 
Stove/Furnace Make: Hitzer
Stove/Furnace Model: 608 Energy Master I Stoker

Re: Reading Allegheny temp overshoot

PostBy: satza On: Mon Apr 02, 2012 9:07 am

I tried changing the thermostat for a two degree setback. Is there actually any point to using the setbacks? Does anyone actually see less fuel usage from it?
satza
 
Stove/Furnace Make: Reading
Stove/Furnace Model: Allegheny

Re: Reading Allegheny temp overshoot

PostBy: Hot Rocks On: Mon Apr 02, 2012 11:35 am

I have never used the set back. I think most people don't use it. If you do use it I would start with a 2 deg. difference then keep adding 1 deg. to see where your temp. overshoot is to much
Hot Rocks
 
Hot Air Coal Stoker Stove: Hyfire II
Coal Size/Type: Rice
Other Heating: Water Coil

Re: Reading Allegheny temp overshoot

PostBy: WNY On: Mon Apr 02, 2012 5:42 pm

WAY too much temp. swing for it, it will feed, and feed and feed to make up the difference and normally overshoot.

COAL is NOT like a gas furnace, it takes TIME to respond, it not like it can be shutoff immediately at the temp. setpoint, it will take and hour or more for the temp to come back down and stabilize.

If you read some of the posts about using the Coaltrol, most of us do NOT use the setback, if you do, only use it a few degrees and give it at least and hour before you want the temperature setpoint.

Most of us just leave it a set temperature.
WNY
 
Hot Air Coal Stoker Stove: Keystoker 90K, Leisure Line Hyfire I
Coal Size/Type: Rice
Stove/Furnace Make: Keystoker, LL & CoalTrol
Stove/Furnace Model: 90K, Hyfire I, VF3000 Soon

Re: Reading Allegheny temp overshoot

PostBy: satza On: Mon Apr 02, 2012 10:05 pm

Does anybody know if the heat loss factor(hlf) setting affects how the firing rate decreases? That is the one thing I haven't played with yet
satza
 
Stove/Furnace Make: Reading
Stove/Furnace Model: Allegheny

Re: Reading Allegheny temp overshoot

PostBy: 2001Sierra On: Tue Apr 03, 2012 12:06 am

Yes the technician in me has looked at all the settings . HLF I believe sets how fast the stove responds, ramp up and ramp down depending on what the temp calls for. I believe mine is cranked up 1 value, because I routinely open a door in the evening to my garage man cave and the bride gets cold in the family room where the stove is.Remember we are heating with small locomotives, yes they will, yes they can, but their time frames are more in biblical time than modern time. Not really a bad thing when you enjoy the benefits of our economical heat. I tell my daughter if you are warm open a window :!: Who does that with oil :?: :P
2001Sierra
 
Hot Air Coal Stoker Stove: Keystoker 90 Chimney vent
Coal Size/Type: Rice
Other Heating: Buderus Oil Boiler 3115-34
Stove/Furnace Model: Keystoker 90 Chimney Vent

Re: Reading Allegheny temp overshoot

PostBy: WNY On: Tue Apr 03, 2012 5:09 am

Yes, it changes the ramp up response. I think I have mine at 2, since my stove is in the basement and the thermostat is in the living room, our house cools down fast at night. Usually only about 1 degree difference when the temps start changing. I still only leave mine at a certain temperature all the time, and only change a couple degrees when needed. keeps more even temps.
WNY
 
Hot Air Coal Stoker Stove: Keystoker 90K, Leisure Line Hyfire I
Coal Size/Type: Rice
Stove/Furnace Make: Keystoker, LL & CoalTrol
Stove/Furnace Model: 90K, Hyfire I, VF3000 Soon

Re: Reading Allegheny temp overshoot

PostBy: WNYRob On: Tue Apr 03, 2012 7:37 am

Like the others have mentioned, the HLF setting only jump starts the rise in feed rate to meet a higher set point, it doesn't affect the time it takes to lower the feed rate after the thermostat has been satisfied.

When you have a big set point change to increase your house's temperature, usually your feed rates will climb very high. Once the thermostat is satisfied it takes a long time for the feed rates to come back down to near "idle mode". I think the rate of descent on the feed rate is a set speed, so no matter if you are 1 degree or 10 degrees above your thermostat's set point, the feed rate will still descend at its set speed.
WNYRob
 
Hot Air Coal Stoker Stove: Keystoker Koker controlled with CoalTrol

Re: Reading Allegheny temp overshoot

PostBy: Bity454 On: Tue Apr 03, 2012 8:01 am

Is this plumber?
Bity454
 
Hot Air Coal Stoker Furnace: Alaska 140 dual paddle
Hot Air Coal Stoker Stove: Leisureline pioneer
Coal Size/Type: Rice
Other Heating: Good looking wife : )