We are going to buy a house built in 1973.It is a split foyer of almost 2700 sq.feet.We are planning on replacing the original furnace.I am pretty sure we want a 90% furnace.Was wondering if it is worth the expense to go to a 96% dual stage furnace.I think it runs around $500 more. Any input would be greatly appreciated.

 

If your budget allows you to buy a 2 stage gas furance. go for it! it will add alot of comfort in your home....and save money on your gas bill.

This is how it works, if your dealer didn't show/tell you how...

The furnace is going to fire off on low flame (about half BTU Rating) and the fan will also run at a lower speed (Depends on model) and your just going to get an even low air flow heat coming out of your vents.. After an X amount of time. if the t-stat is still calling for heat, then the furnace will jump up to high flame (Full BTU ratings) and brings up the fan to higher speed (Depends on model) and should help bring the temp up...

On some model it uses a DC fan motor and it runs very quiet! and also uses 40% less electricy vs the standard fan motor.. The DC motor can slowly incress speed or decreese speed as needed for your call of heating and cooling.. On the DC motor they like to have you run it all the time and that moves the air around slowly , and also it's passing the air filter all the time for cleaner air in your home.

The furance will know how long it took to heat the last time.. so when it fires up next time. it's going to run low for that amount of time.. and if it gotten colder and it takes longer to heat up than the last time, then it will go into high.

Many people ask why low??? Well, your useing less gas and lower heat blowing out of your vent on a fall day. or mild spring day when you need to get the chill out of the air, not a blast of hot air and feel warm and then feel cool.. meaning a big swing in temp.. With the big swing in temp the person will feel cooler when the temp falls.. (heat set at 68... 67 Heat is called for... furnaces runs..... blast of heat.... temp rises fast to 72 on a fallspring day.. system shuts off..) there you have about 5 degree swing.. It may not sound like much. but it is. On the two stage, heat set at 68... calls for heat at 67.. systems runs on low flame.. slow and even heat blows.... slowly rises to 69... system shuts down.. fan runs low and moves the air around evenly...) or a better word for the 2 stage is even heat like hot water heat!

 

THank you. I will look into this and ask the contractor.

Can you also please give input on if furnace should be coiled to ac via AC or if it should be done the other way as in original post.

 

sorry i posted in the wrong thread.