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Boiler and Indirect Questions
IBC SL 85k - actual output of 79k BTU max and 10.1k BTU min
IBC BTI 55
design temp = ~30k BTUs @ 63 delta T (70 indoor temp & 7 outdoor temp)
~10k BTUs @ 15 delta T (70 indoor temp & 55 outdoor temp)
~2000 sqft of heated space in the state of PA
Plan to use panel radiators @ a design temp of 140 degrees
#1) Based on my low heat load, I should not create heating zones, instead keep it one zone for the entire house?
#2) If the outside temperature does reach 55 degrees or more, I should turn off my heat to prevent the boiler from short cycling(see heat loss above)?
#3) Is it OK to use my boiler strictly for my indirect while I prepare for the hot water heat conversion, even if this becomes a long period of time?
#4) Is best to keep my indirect @ 140 degrees?
#5) What temp water does the boiler output when heating the indirect to 140 degrees?
#6) When an indirect takes priority, that means the boiler will stop heating the home for however long it takes to meet the DHW demand?
55 gal tank * 8.34 weight of 1 gal * 10 degree on/off diff = 4587 BTUs
79000 max BTU output / 60 minutes = 1316 BTU / 4587 BTU = 3.5 minutes of firing time
10100 min BTU output / 60 minutes = 168 BTU / 4587 BTU = 27.25 minutes of firing time
When my indirect is just maintaining temp, based on the above formula, it will require 4587 BTUs. My boiler will automatically find some happy medium between 10k and 79k BTUs, so it is not short cycling?
#7A)..and a side question..what is the ideal run time for a boiler?
52 degree ground water temp
140 DHW temp
88 degree delta * 8.34 = 733 BTUs required per gal
79k BTUs / 733 / 60 = 1.79 GPM of potential endless water?
So, when there is an actual demand on my DHW from say a shower, which will be 2.5 GPM @ 10 minutes. How many BTUs is my boiler outputting? ..and how long is it actually running?
I am just trying to fully understand how everything works. Thanks for your time and help.