Tips on Choosing a New Furnace?

TromboneAl

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Looks like our furnace has bitten the dust. Any tips on the best type to get (propane, 2,000 sq ft house)?
 
We like the 'random fan' feature (I don't know the technical name) on our furnace. We used to use it in our old tri-level to redistribute the air because the top floor would be hot and the bottom floor cold and the middle floor with the thermostat just right. But in our new 2000 sq ft single floor house we still use this feature. The thermostat is in the middle of the house in a hallway. the east bedroom gets overly hot in the morning, and the west bedroom gets overly hot in the afternoon. But the hallway is a perfect temp, so the furnace or air does not come on! So the random fan feature helps redistribute the air around the house.

Some people say a two stage furnace will help with the hot and cold spots, but I don't have any experience with that.

If you get a furnace with a 90 or above rating, you might be able to qualify for a rebate of some sort.
 
Get a 95% high E (or better) condensing furnace.
 
We like the 'random fan' feature (I don't know the technical name) on our furnace.


It's called "circulate". Fan runs part of the time even when not heating or cooling.



I love my Trane S9V2 furnace. It has a variable-speed blower which is designed to run 24/7/365 if you so choose, which I do (it runs at a much lower level when the furnace isn't heating or cooling and the noise is barely noticeable). With the old furnace, the upstairs was warmer than downstairs, year round. Now temps are much more even throughout the house. Another advantage of the variable-speed blower is that it ramps up and down gradually, so you don't get the sudden burst that shakes the whole house when it turns on.
 
As I recall, you live in a mild climate. One option might be to go for a heat pump, depending on what you pay for propane and electricity.


In any case, it is useful to do a real manual J calculation to see how big the furnace should be. Installers tend to either replace with the same size or use a rule of thumb that defaults to a bigger furnace. This causes the furnace to heat quickly then shut off, then repeat which causes inefficient and uncomfortable short cycling. If money is not a big factor, a two stage or variable output furnace is really nice as it gives the best of both worlds.
 
It all depends on the climate you live in, and the cost of electricity. You say you have propane, but it's very expensive to run.

I'm in the Midsouth, and we experience all four seasons--from very hot to short periods of very cold. I have a 3 bedroom lake house, and when my Trane heat pump gives up the ghost I'm switching to two ultra high efficient mini split systems with numerous "head units". The outside compressor is a variable speed inverter unit that only runs fast enough to cool or heat the space. My HVAC contractor has one in his house and he loves it.
 
As mentioned in your post in the other thread, I don't think you need a new furnace, you need a competent tech.
 
In the region where I live most homes heat with firewood. Second is fuel oil, then LPG or propane.

We heat our 2400 sq ft home with firewood.

My woodstove heats water, which circulates through a thermal-bank downstairs, and then through our radiant heated floors. So we have a big woodstove in the center of our home, much of the heat is stored and re-distributed throughout our floors.

I live out in the boonies. I own a mixed-use commercial building in the city. It is heated via boilers in the basement [originally oil-burners that were converted to LPG 5 years ago when the city got LPG installed under the sidewalks] and steam radiators.
 
Running fan continuously to circulate air is a comfort advantage. Also are separate fans in high ceiling areas.
 
Can’t tell where you live - advice without knowing doesn’t help much.

Also, don’t know what is wrong with current system, but I always dig too deep ��
 
As mentioned in your post in the other thread, I don't think you need a new furnace, you need a competent tech.

+1. Rental furnace stopped working. Tenant called several Places. All said,
You need a "new" furnace. Did not want to talk about repair. Finally, got a hold of independent Tech. Came out, diagnosed situation, Replaced a "resistor", Less than $50. (Furnace less than 10 years old).

Problem, Now days, so difficult to find "repair" people. Most just want to "replace". More profitable.
 
In the region where I live most homes heat with firewood. Second is fuel oil, then LPG or propane.

We heat our 2400 sq ft home with firewood.

My woodstove heats water, which circulates through a thermal-bank downstairs, and then through our radiant heated floors. So we have a big woodstove in the center of our home, much of the heat is stored and re-distributed throughout our floors.

I live out in the boonies. I own a mixed-use commercial building in the city. It is heated via boilers in the basement [originally oil-burners that were converted to LPG 5 years ago when the city got LPG installed under the sidewalks] and steam radiators.

Is this information going to help the OP with his question?
 
Have not heated with propane since my wall furnace in a converted lake house in CT decades ago. Was 750 sq ft and actually worked well. That was a few decades ago.

Currently in metro Atlanta so we do get some serious cold snaps. Have a natural gas Lennox furnace now in a 1800 sq ft ranch style house with a partial basement that is also heated with this furnace which is twelve yrs old. So about 2500 sq ft altogether. Very happy with its performance. Also was happy with the Amana furnace it replaced but could not get that brand locally anymore back in 2006. The Amana lasted 30 yrs over three owners of the home, and was still working but the rustiness, inefficiency, and age concerned me.

Hope you get this resolved soon. Sorry I dont know enough to be of more help.
I do agree that you need a better tech regardless of whether you end up replacing or repairing. I found my very good tech through a recommendation form a church elder. Perhaps you could do best by asking locally among friends and acquaintances.
 
+1 converting over to Minisplit ductless system if you live in a moderate climate area. A 24K BTU system would more than likely work great, and have systems that have 3 & 4 inside units available. The Inverter technology that matches the needed load of the house is amazing. Most comfortable heating/cooling and super efficient system I've ever had.

If you are a competent DIY, these are easy to install and can buy online for around $2000-3000 depending on how many inside units. Vacuuming the system down and opening the supplied gas charge needs to be done by a HVAC Tech if you don't have the proper equipement.
 
We installed a Bryant Plus 95I maybe 15 years ago. This is a high efficiency unit with PVC pipe intake for outside combustion air and PVC pipe outlet for combustion products. We were quite pleased with it, particularly with the always-running low level fan because it evened out the temperature in the house.

About 5 years ago, though, it failed and would not turn on. Long story short, the problem was that the heat exchanger, which is constantly bathed in corrosive gasses corroded so badly that the safety switch triggered due to low flow. About $500 later out of pocket plus some warranty credits, we now have a new heat exchanger which is deteriorating as we speak and will fail again. Why? The unit is fabricated from galvanized mild steel instead of stainless as it should have been. We will never buy a Bryant furnace again.
 
It's called "circulate". Fan runs part of the time even when not heating or cooling.



I love my Trane S9V2 furnace. It has a variable-speed blower which is designed to run 24/7/365 if you so choose, which I do (it runs at a much lower level when the furnace isn't heating or cooling and the noise is barely noticeable). With the old furnace, the upstairs was warmer than downstairs, year round. Now temps are much more even throughout the house. Another advantage of the variable-speed blower is that it ramps up and down gradually, so you don't get the sudden burst that shakes the whole house when it turns on.

+1.

Our Trane HVAC was installed spring 2017. It has the recirculate feature - wonderful redistribution of the air to even out warm/cold spots.

We chose Trane because the 1999 unit was still purring like a champ. We replaced it as we didn't want to scramble for service if it sh!t the bed in Jan or Jul.

Look at where you live before going overboard on high efficiency. In our case the A/C works hard J-A-S. The furnace does chores D-J-F, the other six months, everything is goofing off. Miami or Fargo? Different story. :D
 
I am out in the country and have propane, but with a heat pump as the primary. Propane is backup. Rarely need the propane, the newer heat pumps are very efficient and work down to lower temps than older ones before switching over to the backup heating.


X2 the variable speed blower is a good feature
 
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