We live in an A-frame home, 1300 square feet, in northern Wisconsin. The basement has a sand point well that has a 20lb well pressure tank. We have a 96k Burnham propane boiler used for hydronic heat that is about 20 years old and a conventional gas water heater for domestic. We noticed our gas bills increasing over this past winter. Our gas company told us we were using 15 gallons of propane per day. We called two companies to take a look. One showed me a picture on his phone and explained the heat exchanger looked bad and questioned our water quality, told us it could fail at any time. Another company said our spirotherm air eliminator wasn't doing its job and needed replacement. Regardless, I decided it was time to upgrade. I had planned on a high efficiency combi boiler but I'm certain our water pressure could not keep up over time. For example, if my wife is watering the garden I can't flush the toilet. We can take endless hot showers though and overall the low water pressure isn't an issue for us. So now, I'm thinking about a new boiler just for the hydronic heating and keeping our old water heater for domestic. I was thinking perhaps a Rinnai - 112K BTU - 95.0% AFUE - Hot Water Gas Boiler might work in our situation. Would appreciate any advice or boiler recommendations for us.