Just because a motor works on 1 speed, doesn't mean all speeds work, and that it won't overload the board again, and burn out the new board.
FWIW- Ok, bad board. Change it. I always bypass the board and vet the motor. If the amps are OK, then I wouldn't feel the need to condemn the motor. Either way, there is a difference between "inoperable" and "recommend replacing". I think it depends on how sure I am of the original cause of the failure.
So I do appreciate all the advice here. It looks like I may have tickled a couple people the wrong way with my questions. I will say that I'm a firm believe in researching darn near anything I do, on the internet...with the information out there..and it being mostly free you'd be stupid not to. The real challenge is what you do with the information...if it's actuate..and how you process it.
I will say that neither technician was welcomed back for the repair. Neither could tell me in any kind of detail (other than it's 'bad') why they were replacing the parts they recommended.
I did learn a lot about HVAC during this little ordeal, the fix was a simple one and cost me less that a 12 pack and a couple hours of my time. The part cost more to ship that it actually cost.
One thing that I was amazed at is how simple the logical side of a furnace\AC unit is. The control board is merely a small series of switches controlled by relays. A simple test of the 'BLMT' relay showed it was bad...it was replaced (about 3 weeks ago) and I'm back up and running.
Now why did that relay fail? Was the motor drawing to much amperage at start up? What it just a tired 12 year old part? Guess time will answer that one
Funny but ironic parallel. Last week took my car to a corner shop for a NYS inspection and oil change and was told my alternator was going bad (but yet fully functional). I moved a little over a year ago so I don't have 'my' guy for car work yet.
The mechanic took me into the garage...showed me on a meter when under load the alternator was falling below 12v. He then hooked the meter up to the car next to it and under load was 13.5v or something like that.
It took him about 5-10 minutes to show me and explain why it should be replace.
Now changing an alternator is a pretty simple job...yet I had no problem at all dropping the car off this morning for him to replace it (that reminded me of this thread). My truck is due for an inspection in November...can ya guess where I'm gonna take it?
Thanks to every one who responded..even the people that felt insulted that I questioned the original 2 repairs guys estimates.
I'll be sure to post back if my house erupts in a fiery infernal
Originally Posted by simplyrollin
i have to agree with this as to cause & effect in most of our
Originally Posted by jrpsimivalley
service work. ive been to many calls where the problem was repaired but
the cause had not been addressed & we had the same repair again.
Your simple test of the relay might tell you about the motor as the potential root cause. Did the low voltage winding fail or the high voltage contact?
The reason I support the position you took is because since the mid-1970's I've seen far too much awfully incompetent H-VAC service work.
Originally Posted by MonsterBash
The reality that a motor isn't working, of course, doesn't mean it is bad. There can be many reasons, such as bad relay or points, or bad conductors in the electrical circuitry, etc.
If anyone was there, I would show them with my test instruments what was causing the problem & why. If they weren't there everything would be briefly explained on the billing.
Shophound is an expert & he would have explained why it would be good preventive maintenance to replace an old worn blower motor.
I witnessed a lot of good compressors being condemned as needing replacing when it was a run capacitor, a potential start relay, a bad overheated burnt-off terminal connection even leading to requiring replacement of the overheated conductor, on & on.
Service calls should be fully transparent as to what the problem is & it's cause, if you can't do that, then you need further training before you do service work. That is my opinion...
I always tried to save the customer as much money as possible, while doing a thorough service call that would expose any latent problems, - equipment or duct system/airflow inefficiencies, etc.
You ought to be there to do right by your customer, - PERIOD.
If your furnace is 10 years old with the original blower motor, then you'll be replacing it especially if it is used for heat and cooling. I can only assume the company was replacing both the control and the motor because of their experience with older blower motors and unhappy customers when only the board is replaced. Since you've fixed it yourself, then I'm sure your wife will make sure and call you when the old motor gives up the ghost. I agree with posters who said they'd make a "recommendation" about the motor and just replace the control, but sadly sounds like neither company did this. They left oil ports out of blower motors a number of years ago, and seems they now last about 10 years. If I were you, I'd think about keeping a motor around!
Do you also take your car to two mechanics when you need a car repair?
Challenge yourself, take the CM test --- Certificate Member since 2004 ---Join RSES ---the HVAC/R training authority ---www.rses.org
I was replacing the A-coil in a Goodman Gas furnace Thursday and I like to check the heat exchangers at that point Just in case and it just so happens guess what I found? A cracked H/E.
Originally Posted by motoguy128