Last post discussed my software changes to shutdown the boiler in a controlled fashion, these changes included adding a button to choose the shutdown option. I now have added two more buttons. This allowed me to have more choice in the form of a menu system. As I am sure you all know an Arduino program, called a sketch consists of two main portions a start section and a loop section. The start section is only done once and the loop section as the name implies runs over and over again. In the start section I added a menu section that forces the user to choose first, continuous or timed.
If you choose the continuous option you’re done choosing anything, except the ability to shutdown the program and the program resumes it’s normal function of running the pellet boiler. If you choose the timed option the software takes you to a second menu screen showing the current time, a choice to choose a proposed shutoff time 3 hours later and a choice to increase the proposed shut off time by an hour. Again if you choose the proposed shutoff time the program asks for a confirmation time and if you choose another hour that choice is now shown.
The system is simple to use at this point but needs error messages and further programming to make the software more robust. Tor example if you choose past 24 hours you either need to add a date component so that the program doesn’t just choose to shut off in an hour later or as I think if you are going to run it for more than 24 hours you should just choose continuous. I may change my mind on that but that’s my thinking at this point. Time, it’s all time.
On a side note in another iteration I will probably get smaller buttons and place them closer to the LCD, but for now this is the configuration. The buttons are pretty cool, I got them from http://www.sparkfun.com p/n COM-09336. There is a limit switch on the bottom which is really easy to solder to as well as being replaceable if needed. They have a nice positive feel. Again I might not buy this switch again because of it’s size but I do like it.
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?