Start of a new Burner Design
Posted: November 3, 2014 Filed under: Burner, Homemade Boiler | Tags: Arduino boiler control, boiler, Burn test, burner, homemade chip boiler 1 Comment
A friend with Solidworks has offered to draw up a new burner, so I thought I would post a few pictures of the old burner to help with dimensions. Here’s a picture of the uncleaned burner with about two inches of ash build up in the bottom of the burner.
Side view uncleaned burner with tape
The tape measure in this view gives a little help with size. Originally the back flap was designed to help with air flow a sort of chimney effect, however this was of limited help and probably helped trap ash as do the high sides.
Top view showing hole size
The larger holes are 1/2″ and the ash still doesn’t fall through unless stirred.
HDD vs. Pellets Update
Posted: January 14, 2014 Filed under: Arduino, Homemade Boiler, Testing | Tags: Arduino boiler control, homemade chip boiler Leave a commentIt’s been a cold ride here in New Hampshire for a few weeks. However, like a campfire, on average we may end up less than average on HDD’s for the month. I say like a campfire, because it always seems that one side is too hot and one too cold to really enjoy it, however on average….It’s raining hard here today, so once again the snow is leaving. This will ruin the skiing and winter sports and yet it’s really too cold to enjoy summer sports. Winter in Northern New England has become a lot like southern New England. But that’s a different topic.
The pellets seem to be a pretty steady 14HDD per bag. And so a ton this time of year lasts about two weeks, maybe a little longer. We bought our first ton this year, I was using up old stock and we bought a ton from Tractor Supply, their brand. I am liking them a lot, they seem to not cause any ash build up problems at all. I will buy them again. If you add up all the bags used and divide by 50 bags/ton we are at 4.22 tons heating season to date, for a total cost of $947.39 at the cost of $224.50/ton.
2013 in review
Posted: January 14, 2014 Filed under: Arduino | Tags: Arduino boiler control, homemade chip boiler, Software Leave a commentThe WordPress.com stats helper monkeys prepared a 2013 annual report for this blog.
Here’s an excerpt:
A New York City subway train holds 1,200 people. This blog was viewed about 7,200 times in 2013. If it were a NYC subway train, it would take about 6 trips to carry that many people.
Click here to see the complete report.
HDD’s vs. Pellets Part 3
Posted: December 17, 2013 Filed under: Homemade Boiler | Tags: Arduino boiler control, HDD, HDD vs. Pellets, Heating Degree Days, homemade chip boiler Leave a commentThe HDD’s reported from Weather Underground was 324 for the week of December 8-14 and I used 24 bags of fuel, more than would have been calculated by a simple ratio based on last weeks fuel usage, however very close to the trend line of the original scatter plot which I will post again here. So as time goes on the prediction gets a bit better. 
It’s shaping up to be about 13.5 HDD’s per bag of pellets, I have made minor changes to the software so, I think these numbers are getting more stable as time goes on. Note that December 2012 for the first two weeks added up to 431 HDD compared to December 2013’s first two weeks 548 HDD.
Minor Software changes can make life much more convienient
Posted: October 15, 2013 Filed under: Arduino, Homemade Boiler | Tags: Arduino, Arduino boiler control, homemade chip boiler, Software Leave a comment
This time of year in New Hampshire it is warm days and cool nights. Pleasant for the most part but it is still fall. There can be some rainy raw days that need a touch of heat and to heat the hot water or maybe the day is warm enough but just cloudy so you want to heat the hot water for showers. So in other words the boiler can often run for 3-4 hours per night, maybe one or two evenings per week.
Shutting the unit down before the upgrade consisted of unplugging the unit which includes all the controls except the draft fan. This of course shuts off the feed and everything else but the fire still burns the remaining fuel. I keep the draft fan on to minimize any smoking that might occur otherwise. I live on the second floor of the building and the boiler is on the first floor so typically I would walk down unplug the unit, take a shower and then go back down and unplug the draft fan. More than once I have had to go down later after forgetting to unplug the draft fan. So I added a physical button, the Attn button, to the front of the control panel, and rewired the control box to relay control the draft fan. Now with a minor software change made I can go down hit the button and the unit shuts the auger feed immediately and then after twenty minutes turns off the relay for the draft fan. It’s so cool my girlfriend wants to go push the button. Can life get any better?
Fire!
Posted: April 23, 2013 Filed under: Arduino, Data logging, MicroSD card, Testing | Tags: Arduino, Arduino boiler control, Cheap green heat, chip boiler, DIY, homemade chip boiler Leave a commentWell of course there’s fire in the burner that’s how it works. After today however the Arduino should be able to sense the fire since I added a photo resistor, commonly known as a flame sensor, bought at a furnace supply store. With the Arduino’s ability to sense flame, the addition of automatic self starting should be enabled. The ability to determine if fuel is building up should also add safety to an already proven safe unit.
The sensor I obtained is a flame sensor used in a normal oil or gas fired burner. The flame sensor allows me to sense the light corresponding to a fire currently burning. The sensor cannot determine if the fire went out or if the flame sensor can no longer see it but functionally it makes no difference to me. I am interested in either condition and the response is the same to both conditions, turn off the fuel feed. If the fire went out, no need to keep feeding fuel, that will simply clog the feed chute and make a mess. If the fuel has backed up the feed chute so much as to shield the flame sensor, there is excess fuel, turn off the fuel feed. Physically the sensor is mounted to “look” through the back of the feed slide. This positions was chosen purposefully to determine if fuel was backing up.
Because the flame sensor is a resistor, I am using a voltage divider circuit to measure the voltage and then using the software to check the voltage with a if – then statement. The software determines if the voltage is high enough to indicate flame or too low indicating dark. I have been recording various sensor data to the micro SD over the heating season, so I will record the voltage overnight and we can see the range of data tomorrow. If anything this should be a good time of year for the test since the fire is needed to maintain the temperature in the building, it is mid 30’s F here today, but the fire is not required to be too vigorous since the temperature is not extremely cold.
Pictures and data to follow.
Fuel savings built into the software
Posted: April 16, 2013 Filed under: Arduino | Tags: Arduino, Arduino boiler control, DIY, Green Energy, homeade chip boiler, Pellet Boiler, Software Leave a commentI added a function to check for the time of year and hour of day to shut the boiler down automatically, I mentioned this in the last post. But as the days get warmer I wanted to make additional changes. I probably ought to be calculating the HDD and comparing to the present outside temperature to calculate a dynamic time needed for adequate heat, however that seemed too complicated so I wrote a simple function to check for date and time. At this time of year it shuts the boiler off at midnight. In March it ran until 3 am.
void FuelSavingsDateCheck() {//start function
DateTime now = RTC.now(); //get the data from the RTC
Month =now.month(),DEC; //get the month from the RTC
Day =now.day(),DEC; //get the day from the RTC
hour = now.hour(),DEC; //get the hour from the RTC
if (Month ==12 && Day <15) //month of December before the 15th
{//start if section
if (hour >3 && hour <9) //shut off time of 3 am
FuelTest =0;
else
FuelTest =1;
}// end if section
if (Month == 3 && Day >15) //after March 15th
{//start if section
if (hour >3 && hour < 9) //at 3am shutoff burner
FuelTest =0;
else
FuelTest=1;
}// end if section
if (Month == 4) //month of April
{//start if section
if (hour ==0 && hour < 9) //midnight shutoff
FuelTest =0;
else
FuelTest=1;
}// end if section
}//end function
The view from April, Daylight savings time adjustment for your RTC
Posted: April 3, 2013 Filed under: Arduino | Tags: Arduino, Arduino boiler control, Cheap green heat, Energy conservation, Heating, pellets, RTC, Software Leave a commentThe boiler has worked flawless all winter, I am happy with the software and hardware but with all things mechanical there is room for improvement. I have just started my 7th ton of pellets. And I really don’t want to get into my 8th and don’t think I will have to, especially if I institute some energy conservation in the software. This is the time of year that I would normally burn what my grandmother called a “trash fire”. In her case it was some cardboard boxes from the trash and maybe an odd shaped piece of wood or two. Just enough for 3-4 hours in the evening, letting it burn out overnight since the days get up to 40°F or 50°F there’s no need for more fire than that. Later in the month most of the nights will be above freezing. But I still want to light the boiler in the evening mostly for the hot water and then turn it off at 2-3 am, so I wrote that into the software and it has gotten the consumption down to 1-2 bags per day. I also added a function in the software to change the real time clock for Daylight savings time and back automatically. It’s not fully tested but I think it will work OK.
void DaylightSavingsSchedule(){//start function
if (Year ==2013 && Month ==11 && Day ==2 && hour ==2&&DaylightTest ==0)//fall back an hour
FallBack();
if (Year ==2013 && Month ==11 && Day ==4 && hour ==2&&DaylightTest ==1)//reset flag
DaylightTest =0;
if (Year ==2014 && Month ==3 && Day ==9 && hour ==2&&DaylightTest ==0)//spring forward an hour
SpringForward();
if (Year ==2014 && Month ==3 && Day ==10 && hour ==2&&DaylightTest ==1)//reset flag
DaylightTest =0;
if (Year ==2014 && Month ==11 && Day ==2 && hour ==2&&DaylightTest ==0)//fall back an hour
FallBack();
if (Year ==2014 && Month ==11 && Day ==3 &&DaylightTest ==1)//reset flag
DaylightTest =0;
if (Year ==2015 && Month ==3 && Day ==8 && hour ==2&&DaylightTest ==0)//spring forward an hour
SpringForward();
if (Year ==2015 && Month ==3 && Day ==9 && hour ==2&&DaylightTest ==1)//reset flag
DaylightTest =0;
if (Year ==2015 && Month ==11 && Day ==1 && hour ==2&&DaylightTest ==0)//fall back an hour
FallBack();
if (Year ==2015 && Month ==11 && Day ==2 &&DaylightTest ==1)//reset flag
DaylightTest =0;
if (Year ==2016 && Month ==3 && Day ==13 && hour ==2&&DaylightTest ==0)//spring forward an hour
SpringForward();
if (Year ==2016 && Month ==3 && Day ==14 && hour ==2&&DaylightTest ==1)//reset flag
DaylightTest =0;
if (Year ==2016 && Month ==11 && Day ==6 && hour ==2&&DaylightTest ==0)//fall back an hour
FallBack();
if (Year ==2016 && Month ==11 && Day ==7 &&DaylightTest ==1)//reset flag
DaylightTest =0;
}//end function
void SpringForward(){//start function
DateTime now = RTC.now(); //get the data from the RTC
now =now.unixtime()+3600; //subtracts an hour from the time
RTC.adjust(DateTime(now.unixtime())); //resets the time to an hour earlier
DaylightTest =1; //flag variable so it won’t go back in time continously
}//end function
void FallBack(){//start function
DateTime now = RTC.now(); //get the data from the RTC
now =now.unixtime()-3600; //subtracts an hour from the time
RTC.adjust(DateTime(now.unixtime())); //resets the time to an hour earlier
DaylightTest =1; //flag variable so it won’t go back in time continously
}//end function
I am considering adding Ethernet capability
Posted: January 14, 2013 Filed under: Arduino, Ethernet, Testing | Tags: Arduino, Arduino boiler control, data logger, Ethernet Leave a commentBy adding Ethernet capability I can write the data I am currently collecting on the micro SD card to a browser directly. This means I could pull up Firefox and go to my Arduino’s IP Address and see the data. This will give me the ability to read the data from anywhere on my home network as well as anywhere I can get internet connectivity, potentially allowing me to review data from a smart phone remotely. Additionally I could control relays from a remote location as well. But for now the ability to ease the data collection and monitor the process remotely will be a great first step. First I have to buy an Ethernet shield. For those of you not familiar with Arduino this means an additional plug-in board that will stack on top of the Arduino pins.
Ethernet Shield
Here’s a picture of just the Ethernet shield, the connection point you see on the front is the plug-in point for the Ethernet connection. This is a RJ-45 connector. I was able to get a 100 foot Cat 5 with installed RJ-45 connectors for $27 at Home Depot.
Ethernet Shield stacked on an Arduino UNO, note upper connection is the RJ-45 Ethernet connection
At present I have already have a prototype shield plugged into my Arduino Uno. This allows me to easily disconnect and update the Uno without disturbing any wiring connections. There are quite a few wiring connections for the RTC or Real Time Clock, the LCD display, the outside temperature thermister, the boiler water tank thermister, the Auger Feed pipe thermister as well as Relays to turn on the Auger motor and boiler tank water circulator. But when I attempted to plug in a prototype shield into the Ethernet shield there was interference with the RJ-45 connection point. The prototype shield would have grounded itself on the metal so I have ordered Stacking headers to extend the height above the shield. More when the headers arrive.
Deja Vu (it got really cold again), Test Plan
Posted: January 3, 2013 Filed under: Testing | Tags: Arduino, Arduino boiler control, auger feed, Data collection, Software, Testing 2 CommentsAfter writing a similar post on 1/15/2012 I find myself saying basically the same thing, after a -10F night the boiler has kept up. Additionally except for a 12 hour period when I made some boiler modifications the boiler has run continuously for 14 days. There are several differences however. The software is 100% better and controlling the temperature to within a few degrees. The burner is now a waterfall type burner that is much safer and runs more consistently. The hopper and auger setup is much more consistent and dependable as a worm and worm gear than the chain and sprocket setup from last year. Most significantly the burner has proved it can run on chips as well as pellets. During these colder nights it is more difficult for the burner to keep up with chips because of the density differences. The chips are much less dense and because of this the auger must feed significantly more of them. The auger motor may need to be changed to accommodate this burning however during weather that does not require so much energy the chips will burn just fine. I could have easily burned chips for most of December with no issues if they had been dry enough. Which brings me to my second topic.
A test plan. I have taken the Holidays off but it is now the new year and time to make some constant progress. To facilitate the test plan I want to make some incremental improvements in the software. The first change in the software is to gather more data to make better decisions. To do this I am going to first add the date and outside temperature readings to both the LCD display and the data collected. By knowing these I can correlate the feed times to temperature and see how close a relationship between them exists. Next I would like to total the run time of the auger per minute and correlate that to both outside temperature and fuel usage. Armed with this additional data I can then make various burner modifications and see the differences if any graphically. The data is good now but could be better. As you can see from the data below the software is not working properly now. The derivative portion of the formula is not contributing at all. This needs to be fixed in the software.
Data collected on SD card
frugaltinker 