Divine GraceBuilding Automation
In 2015 Johnson Heating and Cooling L.L.C. was contracted to design, build, and intall both a building automation system and a two boiler heating sytem at a church and school in Oakland County, Michigan.BAS Page
Tithing once is a good thing, but giving a tithe that keeps on giving is even better! So as not to seem disingenuous, we did get paid for the work that we did, although we also discount the cost of our services whenever we’re able to- if we feel that the cause is a worthy one. In some senses, it’s one way for us to tithe. We feel blessed that God has given us the opportunity to provide our services for His places of worship, and we take a special sort of pride with the work that we do in those structures. Divine Grace Ev. Lutheran Church and School is special to us because David Johnson Jr. (president of Johnson Heating and Cooling, LLC) himself attended Christian schools in his youth. We understand the mission and challenges of Christian churches which support the education of this country’s “next generation”, and we applaud and are grateful for all those who serve God via Christian education.So it was mentioned, “...a tithe that keeps on giving...”. For this project, we were very busy at the time that the proposal was accepted, so we worked with a subcontractor (David Sr.’s company) to help us install the new boilers for the job before the weather shifted in the fall, although, we installed the automation system. From a monitary perspective, our portion of the contract was relatively small, however, it did have a great impact on the final project. It seems very common that many customers and also “would be customers” typically miss an important aspect when choosing options or contractors for certain work. The thing that we’ve seen many customers “miss” is the amortized difference in operational cost of the finished project based on both system structure and the difference in quality between contractors. While it’s understandable, at least to some extent, that a potential customer would not “have a crystal ball” and know ahead of time what kinds of differences could be expected based on using one contractor versus another, it still always seems to amaze me how some customers don’t consider the difference in value that one contractor may provide versus another. Consider the amortized cost difference over the next twenty years and then consider that when it comes to building automation systems, the difference in energy costs based on using one contractor versus another could be as much as 80%- it’s a curious thing to me. Check out CoolingLogic™ for substantiation of this claim. So, for Divine Grace, the boilers needed to be replaced, but also, we felt that it would be in the church’s best interest if they also had an automation system installed. Previously, the church used non-programmable thermostats that kept constant temperatures and had no reset. Providing for reset was problematic because the water in the pipes was very susceptible to freezing in the winter. Basically, if the temperature set points were set down to low settings, while the building was unoccupied, the heat/pumps would stay off for several hours. Because the piping for the radiant heating was near the exterior walls and because the building had a large thermal capacity, the pipes would freeze in the winter if the temperatures were reset. The outer perimeter would reduce in temperature to the point where the water in the pipes would freeze, but the heat would not come on because the center of the building would decrease in temperature more slowly and not call for heat until after the pipes were frozen. Due to the fact that pipes freezing was problematic, we had to work something out.
Code was used which would cycle the pumps intermittently while outdoor air temperatures were below freezing. The cycling of the pumps would not be enough to have significant effect on space temperature, but would however keep the water in the pipes from freezing. Because pipes freezing was no longer an issue, the church was able to use temperature setback. Now, an experienced boiler maker might think “why not put glycol in the system to prevent freezing?”. The answer to this question is quite simple- cost. Why install glycol when writing code only takes a few minutes? Exactly how much would it cost to install AND MAINTAIN acceptable glycol levels in the boiler systems? Also, importantly, glycol reduces the efficiency of the boilers and systems. We opted to stick with water because it cost less initially, it cost less to maintain, and it would cause the systems to last longer. Our solution was so unique, cost-effective, and novel that we gave very serious consideration to patenting the process. So, we saved the church money because we were able to provide for space temperature set-back in a building that was prone to have frozen pipes, but what else did we do? We installed code which would cause the boilers to reset such that we hit the “sweet spot” in the boilers firing cycle, and we also installed modulation dead-bands on the secondary loops such that the boilers would not short-cycle. Basically this means two things, (1) just as a car gets better gas mileage when acceleration is moderated, gas-fired boilers get better gas mileage when their firing rates are moderated, and (2) just as turning off and then restarting your car every block would cause your car to use more gasoline (because the car uses more gas to start than when it simply idles), starting and stopping gas-fired boilers wastes fuel and will cause premature failure too. As it pertains to these topics, the matters relating to boilers are more severe than they are with automobiles, such that hitting the boilers “sweet spot” and preventing short-cycling is much more important for efficient boiler operation than it may be for cars, but then it depends on the specifics. Aside from the energy savings which we were able to provide the church, we were also able to add value because we installed many, many alarms which would alert us of system or component failure. Adding a battery backup simply fortified the system and allowed for more robust communications to the server. In our contract we had stipulated that the church was responsible for proving the static IP address and an internet communication line (CAT-6) to the location of the server, but because of a problem with the church’s internet service they could not affordably provide for the internet connection as per the contract. We kept the ball rolling forward and installed and configured a wireless modem which utilized the cellular tower network so that WAN access to the server could be established. Aside from providing for WAN access to the automation system so that parishioners and the pastor could access the system remotely, we are able to provide remote assistance and send/receive alarms. On several occasions, the remote assistance became valuable because it allowed us to add user names and do things of that sort, which without the WAN access, would have resulted in a service charge needing to be sent. Thank God, we’re busy with our work, and we’d much rather make money by saving customers money, rather than having to drive here and there for things as simple as creating a new user name. To the point- our system saved the Divine Grace Ev. Lutheran Church and School money!