Yesterday, I swapped the pumps on the boiler. I put the 007 on the very short run (30 total feet) to the garage, and what I thought was a 009, turned out to be a 011, to the 200 foot run to the house. As for the house, it has improved with the pump swap, but it's still not where I think it should be. We had a 25 degree night, and it kept up through the night, but if I want to move it up a couple degrees, it has a hard time, and lengthy run time, reaching the new set point. I kept it at 71 in the night, and this morning, I changed the set point to 73, and it struggled to get there. Again.. much better than it was, but not quite what I expected. Bottom line... I haven't fired the propane furnace up since I swapped pumps!!

My thoughts are going to 2 things:
1) The house heat exchanger is 12" X 15" and rated at 72,000 BTUs. The one I had used about 5 years ago, with a different boiler, was 130,000 BTU, Is the current heat exchanger adequate???
2) I have a 2 stage ArcoAire furnace/AC, and the fan is set initially to the lowest speed. Minimal air movement. Once the furnace kicks into the 2nd stage, it goes to a high fan speed. On low, you can't
hear it run. I need to check, but I think it has the capability to run at a medium speed on start up, instead of low, but it can't be controlled through the thermostat. I would need to make that change
on the PC board inside the furnace. Possibly a higher fan speed initially would make a quicker increase in temperature??
Your thoughts......