I have sold sap since 2016 and I'm now exploring purchasing my own evaporator and everything that entails.

So my question is this, on an 4x14 evaporator with hoods and no steam away, concentrateing to 18%, how much oil would I use per gallon of syrup/ per hour of boiling?

I'm assuming an evaporation rate of 180 gallons of sap an hour producing approximately 40 gallons of syrup a hour. Is this realistic?

Thanks for your help in advance.