Yea, I know. Could I be any more vague?
I’ve got a sneaking suspicion my furnace blower motor is on its way out. The furnace is 9 years old, 90% efficient with only one speed. If the motor does go, should I just replace it or replace the whole furnace?
If I replace the furnace, what brand is recommended?
More to the point, what kind of questions should I ask when looking at any particular brand?
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Replies
I replaced the blower motor in my furnace and did it myself. The new electric motor cost about $115.
Thats good news.How long should one expect a furnace to last, generally speaking?
I think home inspectors tell people a furnace will last 20 years.The furnace I have in my house is a 1968 model and it's almost 40 years old and is running just fine.
A furnace should last 20 years or so, though some of the high-efficiency models slightly older than your had heat exchanger problems sooner than that. Basically, a gas forced-air furnace is only worn out when the heat exchanger goes out -- everything else can be replaced (though obviously some lemons can develop chronic parts-crapping-out-itis sooner).
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Jeez,, I must be a dinosaur(I can't even spell it)..My furance is 1955 vintage, and works fine. It claims to be 80% efficient...I have replaced the motor on the blower, and the gas valve(to an electronic ignition. had a Millivolt system). Motor rebuild was $40 and gas valve was $130..My labor...Extra 13% effiency won't pay for itself before I cash it in..
Bud
Yeah, ours lasted over 30 years, and the older units lasted longer (though they were less efficient).
But I frankly doubt whether a 1955 unit is more than 60% efficient, regardless of what the nameplate says. 80%? In your dreams! Remember that no non-condensing unit can be more than 86% efficient, and the closer they get to that number the quicker the heat exchangers corrode through.
You would likely pay for a new 90%+ unit in less than 5 years.
If your view never changes you're following the wrong leader
A single-speed motor probably won't break the bank. I (being cheap and having a Yankee/midwestern "use it up/wear it out" streak) would stick with the current furnace so long as it's not got any other problems. True, newer units are 96%, but it'll take decades to pay off at 6%.
replace the motor yourself,it will take less time than getting a bid for a new furnace.
what makes you think it needs a new motor is it whining or grinding?
i have house's with furnaces that are the origs built in the 50's. like some one said if the heat exchanger is good evrything else is just parts.larry
if a man speaks in the forest,and there's not a woman to hear him,is he still wrong?
Sounds like you are not too familiar with furnace's etc. In our area the nat gas distributor will inspect the furnace if requested. The inspection will reveal whether the furnace or the motor or belt is acting up.
I live in a 35yr old house where we keep the fan going 24hrs a day. We go through 2-3 belts before the motor goes. Changing the belt is easy, simply turn off the furnace, remove the belt and take it to the store and get a new one the same size and then put it on. You should be able to remove and replace the belt without loosening the motor.
You could also elect to have your furnace cleaned at this time, which will also reveal the condition. Sort of combine it all. The cleaning co will likely replace the belt if that's the problem.
Ed
A 9yo 90% furnace likely has a direct drive motor and no belt.In some areas the gas company will do free checkups, but it's more the exception than the rule."Cleaning/adjusting" a gas force-air furnace is overrated, and certainly doesn't need to be done yearly so long as you're good at changing the filters on schedule. But it's not a bad idea to opt for it every 3-5 years, just to have the thing looked over by a pair of more experienced eyes.
If your view never changes you're following the wrong leader
No free checkups in our area unless you've opted to ads a monthly fee to your utility bill, so I think it is time to call an HVAC guy. There's plenty I've tackled successfully on on my own with this old house, but to date furnance repair is not one of them.The problem is that occasionally when the furnace kicks, on the blower won't run. When that happens there is a slightly acrid smell coming from the ducts, kind of like when you run it for the first time in fall and the dust inside burns off. During that time there is a cycling sound, as if the motor is trying to turn but not.I think I'll leave this to a pro, but it's good to know a new motor won't break the bank if that turns out top be my problem.Thanks to all who replied.
Yeah, sounds like the motor may be sticky on starting. Have you checked to see if it has any oil ports?
If your view never changes you're following the wrong leader
That's exactly what my father-in-law suggested this morning. I'll take a look as soon as I return from church.
This is how things went for me.One hot day this past summer my a/c quit. I listened at the furnace and noticed the blower fan was not running.I removed the blower assembly and the motor was frozen up. It looked really old.The blower assembly housing and squirrel cage fan were so dirty I couldn't believe it.I cleaned it all up, got the new motor, and put it back together. I wired in the motor to run at high speed. This improved my air conditioning. I think the old motor was running at medium speed and I had the new motor set for high speed and it worked great. It was much better than before.But I wondered what would happen when the weather turned cold and I cranked up the furnace. I wondered if the furnace would just blow cool air or maybe even cold air due to the high speed of the fan.I turned on the furnace a few weeks ago and it's working great. HOT air coming from the vents. The volume of air is twice as much as before. Anyway, that's what happened to me.Good luck !
Would it work to install some kind of manual speed control switch in order to be able to easily change the speed from low to medium to high speed.
Yeah, you can install a rotary switch or some such (just a SPDT toggle, for two speeds), if you have a multi-speed motor. You must be careful, though, that the switch is a "break before make" variety so that you never energize two wires at once, as this causes problems.With a single-speed motor you could buy the "Router speed control" from McFeely's and wire that in.
If your view never changes you're following the wrong leader
"With a single-speed motor you could buy the "Router speed control" from McFeely's and wire that in."I think that most furnace blower motors or induction with capitor start and/or run.Unlike the universal motors in portable tools or the split phase motors used in ceiling fans the induction motors will stall if you try to lower the voltage..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
i'm thinking you may just have a bad capacitor. next time it doesn't want to come on take the blower motor cover off the furnace. you will have a switch that trips when the cover comes off,hold it down or have the wife hold it down.now reach in with your fingers and give the motor or squirrel cage a little spin. if it takes off you probably need a capacitor,cost about 5.00.
if that doesn't fix it you have a dead spot in the armature and it's time for a motor. they are usually very easy to replace with only to warnings.1 write down the color of wires and where they attach.2 the squirrel cage can sometimes be frozen on the shaft and need some wd40 and gentle persuasions. larryif a man speaks in the forest,and there's not a woman to hear him,is he still wrong?
Thanks. I tried precisely what you suggested and even upon spinning the squirrel cage the blower does not turn - most times.The problem is very intermittent. Sometimes the motor fires right up and the blower works, no extra help required. I did take a good listen while the blower motor was working and with the furnace cover off. I hear a slight squeaking, perhaps a bearing?I'm going to give it a shot and try to replace the motor myself tomorrow morning.One question, do I need to discharge the capacitor before disconnecting the squirrel cage and wires?Seems to me I forgot to do that when replacing a washing machine motor once - the only other time i9n my life I attempted to do anything with a motor other than turn the keys on in my car.
No, no need to discharge the cap. Just don't forget to disconnect the power, and be sure to pay attention to how the wires are connected (and write it down).
If your view never changes you're following the wrong leader
Thanks. I plan on writing it down AND taking a digital photo.
Hey, thanks to you and the others for your posts. I couldn't get anyone out to fix the motor today, so I took it upon myself to replace and viola! The new motor works like a champ.Only out $90 and a few bloody knuckles.
Good to hear. It may have just been a bad start cap, but you'd have to do most of the same work for that, and more fartin' around if you don't quite understand it all.
If your view never changes you're following the wrong leader
Good job Pino. The last time my wife hired an HVAC company to fix our furnace, they charged her $550 to put a new motor in! FKA Blue (eyeddevil)
Thanks Jim. You know, the closest I've ever gotten to a motor was putting the keys in the car's ignition. I thought this would be a really daunting task, but in the end it was quite simple.The only challenge was getting the motor balanced in the mounts. The first two tries resulted in a lot of vibration, but as they say "third time's a charm."The only down side is that now my lovely wife is going to want me to take on all the appliance repairs myself.
I made that mistake early in our marriage. And you've never had a heavier hear than when a small child comes to you with a broken favorite toy and says "Daddy fix". (Repaired the blasted "Farmer Says" toy at least twice, even though it was welded together.)
If your view never changes you're following the wrong leader
Why do you leave the blower running? FKA Blue (eyeddevil)
I live in a colder climate,,Calgary Canada. I leave it running to circulate air which keeps the temp pretty even throughout the house. Our house is a Bi-level with a finished basement. Our cold air returns in the basement are at the floor level which helps prevent the floor area from cooling. I don't want the air at the basement floor to feel cooler than the air at chest height. I can lay on the floor when it's 20 below outside and feel comfortable. It works to keep the air in the basement fresher as well, no musty basement smell.