Hello all. Purchased a home with an older geothermal unit installed. (Installed mid 1990's) My climate dips below -25c frequently in winter months. My geo unit is on full blast non stop and can barley keep up unless wood furnace is used.. The unit is a water furnace premier 2, horizontal loop 4 ton unit. The house is built in 1970's and is 3000sq foot rancher I am guessing the system is undersized. If I run just geothermal no wood assistance bimonthly bills would be anywhere from 700-1000$ And below 15 degrees Celsius on cold days. I am looking to cut that down.. While I am home I run wood furnace all day and load it up before I got to sleep. Fire goes out roughly 2am I wake up around 5:30-6 relight the fire. Bi-Monthly bills while using wood furnace with geothermal only kicking on a few hours a nights is around 300-400$. My first plan of attack would be to insulate the ductwork. Under the house is a non insulated dirt crawl space.. 2' in some areas less than a foot in some areas, my eye can see small air gaps and poor connection points. Searching the forums I can find no one who has a before and after insulated duct testimonial.. There are many snaking ducts under the house which I'm guessing losing lots of heat due to lower air temperatures from geothermal compared to wood furnace. Not only are temperatures coming from geo unit lower then standard furnace but also in some instances running 50' under the non insulated crawlspace before air enters the house. I assume the mild temperature released from unit is cooled to barley room temperature before entering home. So I guess I am asking has anyone under taken this job, and how much roughly monthly on your bill did it save? I would rather not spend a few thousand dollars on insulation and crawl under house for days sealing and insulating ductwork if is only going to make 5$ difference a month.