Contaminated Air Conditioning

Cafarca · 10-21-2017, 09:07 PM

This summer a strange slightly sweet chemical smell started coming through the air conditioner (both heat and cold, both recirc and fresh). A kind analytical chemist friend did some air sampling and found xylene, ethyl benzene, di and tri methyl benzene, and ethyl methyl benzene. I'm withholding my opinion about what this is. Question 1, has anyone experienced anything like this? Question 2, how do you get to the air intake both cabin and fresh? Does anyone have photos of these intakes? I have pulled off covers but cannot find anything that looks like an intake/hole. I know where they are supposed to be.

jnecr · 10-22-2017, 09:53 AM

Quote:

Originally Posted by Cafarca

This summer a strange slightly sweet chemical smell started coming through the air conditioner (both heat and cold, both recirc and fresh). A kind analytical chemist friend did some air sampling and found xylene, ethyl benzene, di and tri methyl benzene, and ethyl methyl benzene. I'm withholding my opinion about what this is.

What did he find in his control sample of air that didn't come through the air conditioner?

BMWrules7 · 10-22-2017, 10:58 AM

Quote:

Originally Posted by jnecr

Quote:

Originally Posted by Cafarca

This summer a strange slightly sweet chemical smell started coming through the air conditioner (both heat and cold, both recirc and fresh). A kind analytical chemist friend did some air sampling and found xylene, ethyl benzene, di and tri methyl benzene, and ethyl methyl benzene. I'm withholding my opinion about what this is.

What did he find in his control sample of air that didn't come through the air conditioner?

Oh, the control? Not much, only xylene, ethyl benzene, di and tri methyl benzene, and ethyl methyl benzene.

Why you ask?

jnecr · 10-22-2017, 12:48 PM

I'm guessing that was a joke?

If the control sample has the same stuff, then there's nothing wrong (different) with the air that came through the A/C.

Beek · 10-22-2017, 02:12 PM

My EMF detector is starting to go off.

stormlv · 10-22-2017, 02:32 PM

Quote:

Originally Posted by jnecr

I'm guessing that was a joke?

If the control sample has the same stuff, then there's nothing wrong (different) with the air that came through the A/C.

+1

Also noteworthy is to know the concentrations that these gasses have been found in?

chiefneil · 10-22-2017, 03:46 PM

Could just be an evaporator leak. There's a distinctive odor when there's a leak. Not sure what all is in refrigerant these days, so no opinion on how refrigerant matches up with the chemical analysis.

cozye · 10-22-2017, 05:24 PM

Sounds like coolant leak in the heater core to me. That would explain the sweet chemical smell and likely the chemical sample

Billfitz · 10-22-2017, 05:26 PM

The smell maybe coolant, but the chemicals are solvents not found in coolant.

Cafarca · 10-22-2017, 08:22 PM

Yes, only outside control. Good question! I would like to find a another car to use as a control. I do not know the exact ppm because the pump we had to pull the samples was really old and not in calibration. The peak (signal) size was the same for 5 minute and 10 minute pulls which means that the tubes were saturated in less than 5 minutes. I thought about the coolant but it really does not smell quite "sweet enough" to be the coolant. Also no ethylene glycol found. The cabin air filter smells the same way.

Cafarca · 10-22-2017, 08:25 PM

Any idea how to get to the intakes?

10-21-2017, 09:07 PM	#1
Cafarca Registered 0 Rep 4 Posts Drives: 2014 335i Join Date: Oct 2017 Location: Georgia iTrader: (0)	Contaminated Air Conditioning This summer a strange slightly sweet chemical smell started coming through the air conditioner (both heat and cold, both recirc and fresh). A kind analytical chemist friend did some air sampling and found xylene, ethyl benzene, di and tri methyl benzene, and ethyl methyl benzene. I'm withholding my opinion about what this is. Question 1, has anyone experienced anything like this? Question 2, how do you get to the air intake both cabin and fresh? Does anyone have photos of these intakes? I have pulled off covers but cannot find anything that looks like an intake/hole. I know where they are supposed to be.
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10-22-2017, 12:48 PM	#4
jnecr Second Lieutenant 114 Rep 243 Posts Drives: 2014 328d Join Date: Mar 2017 Location: Raleigh, NC iTrader: (0)	I'm guessing that was a joke? If the control sample has the same stuff, then there's nothing wrong (different) with the air that came through the A/C. __________________ 2014 328d
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10-22-2017, 02:12 PM	#5
Beek Major 707 Rep 1,170 Posts Drives: Most folks crazy. Join Date: Dec 2015 Location: The Twin Cities iTrader: (0)	My EMF detector is starting to go off. __________________ '16 340xi Mineral Grey/Black Leather, MPSS on 18" 398 Orbit Grey wheels, ZF 8HP50, MPPSK+CF Tips, ZTR, ZMP, ZTP, ZCW, ZDA, ZDB, Black Kidney Grilles. '09 Outback for a beater and grocery getter.
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10-22-2017, 03:46 PM	#7
chiefneil Lieutenant Colonel 772 Rep 1,503 Posts Drives: 2014 335i M-Sport Join Date: Sep 2013 Location: Arizona iTrader: (0)	Could just be an evaporator leak. There's a distinctive odor when there's a leak. Not sure what all is in refrigerant these days, so no opinion on how refrigerant matches up with the chemical analysis.
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10-22-2017, 05:24 PM	#8
cozye Second Lieutenant 327 Rep 261 Posts Drives: 2024 M3 Comp - 328ix (hers) Join Date: Dec 2016 Location: Kentucky iTrader: (0)	Sounds like coolant leak in the heater core to me. That would explain the sweet chemical smell and likely the chemical sample
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10-22-2017, 05:26 PM	#9
Billfitz Lieutenant General 8216 Rep 16,052 Posts Drives: '15 328iX GT Join Date: Jan 2015 Location: New Hampshire iTrader: (0)	The smell maybe coolant, but the chemicals are solvents not found in coolant.
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10-22-2017, 08:22 PM	#10
Cafarca Registered 0 Rep 4 Posts Drives: 2014 335i Join Date: Oct 2017 Location: Georgia iTrader: (0)	Yes, only outside control. Good question! I would like to find a another car to use as a control. I do not know the exact ppm because the pump we had to pull the samples was really old and not in calibration. The peak (signal) size was the same for 5 minute and 10 minute pulls which means that the tubes were saturated in less than 5 minutes. I thought about the coolant but it really does not smell quite "sweet enough" to be the coolant. Also no ethylene glycol found. The cabin air filter smells the same way.
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10-22-2017, 08:25 PM	#11
Cafarca Registered 0 Rep 4 Posts Drives: 2014 335i Join Date: Oct 2017 Location: Georgia iTrader: (0)	Any idea how to get to the intakes?
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