Where do you live? That is probably more important. If you live in MN, I would get a high end multistage because you use it 8 months of the year. If you live in the south I would save the money and spend it on A/C. I live in MN so I bought a high end Lennox and middle of the road A/C. I would never see the return on the high end A/C
New Furnace question.
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Running a 2-stage American Standard for almost 20 years now. Change the filter twice a year and nary a hiccup. Been -10* all week and no issues.
That's what I thought, too. But @Nukeman7 seems to disagree. But in researching my own CPH settings, I've found a plethora of randomness online. I'm open to being wrong
. Then I'll learn something. It's just how I had been reading things. But now I'm going to Google more because past Googling that has come up and I thought I found somewhere reputable info.To the OP: see, I found a ton of ignorance when I was dealing with CPH settings and now I might be promoting my own ignorance I thought was correct. Now I'll research more myself.
Here's what I've been finding in multiple locations from seemingly reputable HVAC places.
So, to the OP, have them specify if they're talking input or output BTU for the furnace as @Nukeman7 and I both seem to be correct, depending on what BTU (input or output) is being discussed.
What Size Furnace Do I Need? - Cagle Service | Heating and Air
When it comes to replacing your furnace or installing a new furnace at a newly constructed location, it's important to know what size furnace that you need.
cagleservice.com
"If a furnace produces an 80,000 BTU output then normally the input BTU capacity produced is going to be higher than 80,000 due to the heat loss during the heat delivery process. And if a furnace produces an input capacity of 80,000 BTU’s, then the output capacity will normally be under 80,000 BTU’s. Most BTU numbers that you see will be input numbers."
How Many BTUs Does a Typical Home Furnace Need? - Overland Park Heating and Cooling OPHC
Kansas City’s cold winters mean that the size of your home furnace is critical for both comfort and manageable energy bills. It’s for this reason why furnace sizing is such a complex task, and why a “typical” furnace BTU rating can’t be given. Common BTU ratings Because home heating needs vary...
overlandparkheatingandcoolinginc.com
The youtube video posted on the thread explains it well.. I have my CPH set at 3 on my honeywell thermostat...Carrier single stage gas furnace...That's what I thought, too. But @Nukeman7 seems to disagree. But in researching my own CPH settings, I've found a plethora of randomness online. I'm open to being wrong
To the OP: see, I found a ton of ignorance when I was dealing with CPH settings and now I might be promoting my own ignorance I thought was correct. Now I'll research more myself.
I was surprised that mine was already set to 3 for the heat so the HVAC tech. knew what he was doing...But it is nice to know what it means and how to change it...
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@RhondaHonda @Nukeman7 Here's a video explaining efficiency input vs. output.
Selecting Heating Capacity - Learning Center
Learn the key factors and considerations for selecting the appropriate heating capacity for your HVAC system.
www.alpinehomeair.com
Edit: The "sizing estimator" by zip code and level of insulation is kind of neat.
My dad considered a Heil furnace. As we looked into them they made it very difficult to get part numbers and when we called their number they more or less told us that they could schedule repairs etc but weren't forthcoming about where to get parts except from one of their dealers. Their website at least a few years ago had very little product specifications or pricing.
I've also noticed that some of the hvac supply places only sell to dealers some to the public. Oddly enough maybe it's just the place near me but if you buy parts out of season ie furnace parts in the summer the parts are significantly cheaper.
Same here, there is only 1 parts house that will sell repair parts to the public and they are like 25 miles away. I just get parts online now.
Here's what I've been finding in multiple locations from seemingly reputable HVAC places.
So, to the OP, have them specify if they're talking input or output BTU for the furnace as @Nukeman7 and I both seem to be correct, depending on what BTU (input or output) is being discussed.
What Size Furnace Do I Need? - Cagle Service | Heating and Air
When it comes to replacing your furnace or installing a new furnace at a newly constructed location, it's important to know what size furnace that you need.
"If a furnace produces an 80,000 BTU output then normally the input BTU capacity produced is going to be higher than 80,000 due to the heat loss during the heat delivery process. And if a furnace produces an input capacity of 80,000 BTU’s, then the output capacity will normally be under 80,000 BTU’s. Most BTU numbers that you see will be input numbers."
How Many BTUs Does a Typical Home Furnace Need? - Overland Park Heating and Cooling OPHC
Kansas City’s cold winters mean that the size of your home furnace is critical for both comfort and manageable energy bills. It’s for this reason why furnace sizing is such a complex task, and why a “typical” furnace BTU rating can’t be given. Common BTU ratings Because home heating needs vary...overlandparkheatingandcoolinginc.com
HowAboutThis is certainly correct and I need to clarify that I was addressing the output BTU value vs. input BTU ratings. It appears that you will need to be clear when discussing furnace size with the contractor as to whether the it is input or output. If the brand of furnace is advertising the input BTU rating, the efficiency will come in to play in regards to the output.
It has been several years since I've seen a Manual J calculation, but I think it takes both input and output BTU values (AFUE efficiency) into account when determining the correct size furnace.
Every time I've used those estimators they way over do it with heating requirements. I know it's somewhat of an educated guess but I've ended up at times with those estimating nearly 2X the BTU output that I actually should have. The cooling seems more accurate though.
Mine came back at 30k BTU needed. It's way less than what is installed which is probably why our furnace takes 5-7 minutes to raise the temp 2°
We installed a new furnace in June last year. There are a few criteria to think about:
1. BTU output (should match the old unit if it kept up in the past)
2. Efficiency - Alberta only allows furnaces with 96% efficiency and up. We went with the 96% efficiency to keep it as simple as we were allowed
3. Burners - single or dual stage burners. low or high setting basically on the flame output. Went with a dual stage burner.
4. Fan - single speed, dual speed or infinitely adjustable. While a bit more complicated in motor control, we went with an infinite speed unit. We have it set to run at 10% all the time and ramp up the motor as necessary to match the burner output and heat requested from the thermostat. This has evened out the cold/hot spots in the house that were present with the 45 year old single burner, single speed furnace we replaced.
The last cold snap with temperatures down to -37C were handled without issue. 2000sf 4 level split with 90k BTU furnace.
1. BTU output (should match the old unit if it kept up in the past)
2. Efficiency - Alberta only allows furnaces with 96% efficiency and up. We went with the 96% efficiency to keep it as simple as we were allowed
3. Burners - single or dual stage burners. low or high setting basically on the flame output. Went with a dual stage burner.
4. Fan - single speed, dual speed or infinitely adjustable. While a bit more complicated in motor control, we went with an infinite speed unit. We have it set to run at 10% all the time and ramp up the motor as necessary to match the burner output and heat requested from the thermostat. This has evened out the cold/hot spots in the house that were present with the 45 year old single burner, single speed furnace we replaced.
The last cold snap with temperatures down to -37C were handled without issue. 2000sf 4 level split with 90k BTU furnace.
What's your square footage and climate? I'm in nearly the coldest place in the US and have a 60K BTU 2-stage for a 2400 sq foot house...it is properly sized.Mine came back at 30k BTU needed. It's way less than what is installed which is probably why our furnace takes 5-7 minutes to raise the temp 2°
Winter is usually lows of 25-40 and highs of 40-50. We just had a "brutal" cold snap with a couple days of lows in the teens and highs in the upper teens or low 20's. About 1250 square feet.
I lived in the Midwest for many years and had a newer home there with a variable speed high efficient furnace. This binary "on or off" single speed stuff annoys me. But insulation stinks out here on the "we love the planet" West Coast. The irony of moving here is how green everyone is compared to the Midwest but they they pay out the nose for houses with essentially a piece of newspaper inside the walls for insulation
"I drive a Prius but mostly heat the outdoor air because we accept crap insulation values in our building codes."I have had 99 percent efficient ones out in the last 4 houses with high seer ac units. The furnaces have variable speed fans and modulating gas valves. Keeps the utility bills cheap but more importantly they keeep the temp within a fraction of a degree at all times and run nearly silently in the background. Single stage is loud since it either at 100 percent power or off. Temp varies a few degrees from when it cycles on and off too.
The variable speed is great for controlling humidity to a set point year round especially when you pair a variable speed high seer ac unit for summertime.
Theses types of units always come with a communicating digital thermostat. This takes in account the local weather and adjust humidity year round for you. Basically a set it up and forget system.
Key is having a great installer for any system you choose. I liked carrier/bryant years ago but I’ve had Lennox put in the last two houses. All companies sell communicating systems as their top line.
You may see many company names out there but there is only really few manufactures of those systems. Just a different name plate and paint go on the units. Carrier Bryant and under those are many sub name plates with carrier being the parent. Lennox has sub brands. Trane American std have sub brands.
generally speaking the more you spend upfront the more comfort and the lower the utility bill.
Don’t forget filtration either. Charcoal filters hepa filters and uv lights help a lot if anyone has auto immune disorders, asthma, copd, allergies, etc
Have company over turn the fan on the furnace and sit by a heating cooling vent and don’t worry about getting sick. Sit by return air duct though u might catch something from those sick guests that had to come over
Hope this helped a little bit. I’ve been down the road before so I thought I’d try to help
Furnaces are rated by input BTU.
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