Community Forums

Grandpadave · 02-18-2012, 03:25 PM

I have a 32' 2004 Seabreeze with 18,000 miles the other day I went out and started it up and let it run for about 5 minutes, and at that time smoke with an electrical burnt smell started coming out all of the dash a/c vents. I immediately shut the engine off and popped the hood, nothing. After I determined that there wasn't a fire somewhere I thought I would start it up again to do some investigating. The a/c wasn't on when this happened but the blower fan was on low. When I restarted the engine, no smoke, let it run for another 4 or 5 minutes, nothing, ran fine, turned on ac and it blew ice cold air. So now I'm really wondering what caused it? Any ideas out there I would appreciate some insight. And there definitely was the smell of burnt wiring and it was smoke. Puzzled in Florida.

ottffss · 02-18-2012, 03:28 PM

Do all the AC fan speeds work? Sounds like one of the blower motor speed resistors. On low, that is the max resistor and thus the hottest one. Maybe the med one failed? On high there is no resistor, see if the med and low speeds really are different.

TXiceman · 02-18-2012, 04:11 PM

Wow, you really did it now. You let all of the smoke out of the motor. All electrical motors run on smoke and when you let the smoke out, it won;t run.

Seriously, I'd check the resistors on the fan motor.

Ken

ottffss · 02-18-2012, 04:33 PM

In addition to running on smoke per TXiceman, it's also possible the resistor melted the holder they are mounted on. It's a phenolic plastic so it too can have "that" unmistakable burning smell of wires. I just thought of this possibility and the motor would still run fine on all speeds - for a while until the resistor falls apart. Here's some pics of these resistors. If it's an Evans Temopcon dash unit their web site has all sorts of info about where you'll find them embedded in the overall blower box assembly.
www.evanstempcon.com
HV218125 - Johnny's AC Parts Warehouse
Snow Goer Snow Goer Forums: Need a blower resistor (can't find one)

Grandpadave · 02-18-2012, 07:27 PM

Thanks for the advice! I will do some more investigating on it tomorrow, and let you know what I come up with.

Grandpadave · 02-19-2012, 10:55 AM

Well, this morning I went out again and started mh turned on dash air and turned to each motor fan speeds waiting between each speed and all the different speeds worked great with no problems. I'm almost wishing I could recreate the smoke, but everything is working great. I really hate to take it in to have it checked out, but probably should just for peice of mind. Pardon the possible misspellings if any, don't have my glasses on.....

Hipshot · 02-19-2012, 04:29 PM

I had a simular experience last fall. We were camped in North Carolina doing the Blue Ridge Parkway. We were in the toad and had stopped at a stop sign in the country when I smelled an oder of fried electronics. There was no smoke only smell. I stepped out of the car and did not smell anything but fresh air. The smell for you old electronics people was that of a fried selenium retifier. I checked every system in the car I could think of and found nothing wrong. That was 6 months and 5000 miles ago. I am still waiting for something to fail.

Dagwood · 02-19-2012, 05:14 PM

You mightn have low freon. That is one syptom is when smoke comes out of the vents. It could be condensation posing as smoke. It is cheap and easy to check freon. I'm not weari9ng my glasses either.

Thewellz · 03-02-2012, 07:44 PM

Where there was smoke there was fire (sounds like a short)..... albeit brief I would have it checked sooner than later, I'm in the "business" so to speak, and the last thing you need is an electrical fire on the side of a highway somewhere.... seen many a vehicle newer and older succum to electrical fires.

Sparky1 · 03-02-2012, 08:06 PM

My Bounder did exactly that last Yr---only when AC was on--Freon NOT low---smelled electrical I tore the dash apart and got to AC fan & electrical (vent) controls found Nothing Burned called Fleetwood & bounder---they had NO report about this event-Haven't happened again.
smoked the entire MH up-

wa8yxm · 03-03-2012, 08:50 AM

Smoke with electrical smell out of the dash vents, but it seems to work ok, and it did not happen again.

First: There are two possible sources of electrical smoke INSIDE the air ducts. One is the blower motor, The other is the motor resistor, this resistor is used to lower the voltage to the motor in order to get "Low" or "Medium" or speeds other than HIGH, it is INSIDE the air passages.

ON SOME systems, the motor is forced air cooled (by itself) and is thus "Also" in the air passages, on other systems, this is not so, Which you have does not matter in this case.

IF the motor had smoked, it very likely would do it every time, and it may well not run properly.

HOWEVER if dust builds up on the series resistor, either because you have been running with the blower OFF, or on HIGH, and you then use a lower speed (IE: LOW) that dust will burn off, it will have an "Electricial Smell" and it is usually white smoke.

Once gone, it's gone, and the problem does not reappear till the dust builds back up.

Note that in this case EVERYTHING WORKS NORMALLY.

I am not saying that is the cause,, but it is one possible cause. You are wise to continue looking into the cause.

I have never seen this in an automotive HEVAC system. I have seen it with space heaters and such.

Sparky1 · 03-03-2012, 09:03 AM

Thanks---it surely Worried me---Fan Motor and Vent control area was spotless. I had the same idea,since Kitty Cat goes with me alot.thanks for your reply.
rich in s.Va.

ottffss · 03-03-2012, 09:49 AM

Quote:

Originally Posted by wa8yxm

...that dust will burn off, it will have an "Electricial Smell" and it is usually white smoke.
...

Dust will burn off and smell like dust. The same dusty/musty aroma when you fire up any electric resistance heater the first time of the season. The smell of burning electrical insulation or Bakelite is unmistakable.

wa8yxm · 03-03-2012, 07:01 PM

Quote:

Originally Posted by ottffss

Dust will burn off and smell like dust. The same dusty/musty aroma when you fire up any electric resistance heater the first time of the season. The smell of burning electrical insulation or Bakelite is unmistakable.

Well, I would normally agree with you... And where you, or I are concerned you are quite likely right..

Where my wife is concerned.. I would not be so sure.

Another thing about overheated wiring.. The "Aroma" tends to stick around a while.