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Buderus G115 w/ Logamatic 2107 & outdoor reset acting wonky

macolo Member Posts: 7
Hello and thanks to anyone in advance for reading this post as it is a cry for help and to try and wrap my head around any potential malfunctions with my Boiler as well as to try and better understand if something is misconfigured.
Approx. 4-5 years ago had a firm replace an existing system in a 3 zone 2200 square foot home built in 1937. 2 zones are forced air and 1 zone baseboard heat. I opted for the Buderus system as it seemed the most desirable at the time, albeit I knew that it being German I’d be completely clueless when problems arose as it is like everything German over-engineered. Anyhow the system components are as such (also see pic):
Buderus G115 Logano
Logalux LT135/1-LT300/1
Logamatic 2107

I believe there is an outdoor reset installed – I see a small white thermo which was installed outside so can only assume that is what that is.
The issues: every so often, I will experience no hot water/no heat. I go check the Logamatic computer display and it reads ERROR. In the past, (don’t shoot me) I simply kill power to the entire unit via the kill switch On/Off. I let it sit for a good 3 minutes or so, then toggle power back ON. Yea, I know idiotic treating the symptom not the issue – Im in IT so reboot…right? Anyhow, I realize these systems are complex and Im in over my head but again looking to gain a basic understanding so Im not fleeced every time someone with barely more knowledge of this system than me, decides to BS me and charge me an arm and a leg only to have the real issue not resolved. Somehow, I don’t feel the system is tuned properly. But anyhow, so that method as been working to get it going again.
Recently though, I got the ERRO output and my usual trick did not work. After fiddling a bit, I decided OK, it fires or tries to but then cuts out and all pressure gauges are at 0 so its just not doing anything no heat/no hot water - nothing. Hmmn, I toggle the AUT switch on the right-side of the Logamatic to MANUAL mode, thinking Ok maybe its something with the computer or some override is toast (I don’t know) and bang she fires in MANUAL mode. I turn the spin dial (left hand side of Logamtic) from its previous AUT setting to somewhere between 140 and 160. I let it be for some days and its running fine. Part of me wants to just let it be as to be honest nobody who comes here including the actual installer seems to know **** they are doing with this unit. But hindsight is 20/20. I cant help myself and so I toggle the switch on the Logamatic back to AUTOMATIC and spin dial to AUT – thinking ok pressure is back in the system so maybe it will pick itself back up and it did for about 12 hours or so. Then, this morning, Im back in no heat + no hot water situation. The zones from the Honeywell 3 zone system are calling for heat and fans for forced air are blowing air albeit cold.

I am at a loss as to what it could be. I realize you guys are pros and Im basically a Neanderthal here trying to understand this complex system with little/no background – however, I would love to have some basic knowledge if someone can provide as to what might be going on here so I can not feel so lost when a tech comes. Also, I keep all thermostats in the house (Honeywell) set to HOLD and 66 – I don’t mess with schedules on the Thermostats just one constant temp all day/night. I am in CT (ffld county) so if anyone knows a reputable legit firm that actually really knows Buderus – I really appreciate if you can offer contact. Thank you