How do you clean your IHKA system?

[shogun]

DIY Car Air-Conditioner Cleaning to remove bacteria & fungi & dirt

Especially the older E32 without the aircon filter need regular cleaning of the system. I am interested to know how you do it. Usually I use one of these aircon foam cleaners. Condenser is relatively easy to check and clean after removing the front bumper and maybe the kidney grill. Drains of the IHKA unit to the floor to be checked also, they are left and right of the center console and the moisture drops usually on top of the transmission.

What about the evaporator? That is the most difficult item, as a lot of dust sticks there. And even difficult to see the result after cleaning. Last time I removed on the center console the left and right carpet cover, removed the heater sword and sprayed there from the rear. Then a friend told me to remove the temperature sensor on the IHKA box left and light, let the aircon run and spray thru these hole with running AC the foam, that means 1,2,4. There are five temperature sensors in the system. http://bmwe32.masscom.net/johan/ihka/ihka.html
1. Passengerside heatercore temperature sensor, 2. Driverside heatercore temperature sensor, 3. Controlpannel temperature sensor, 4. Evaporator temperature sensor, 5. Outside temperature sensor

After dispensing the product, I wait 20 minutes for product to clean the system. During this time I re-install all components.. You will also notice at this time that the product will be draining from underneath the car. The cleaning solution will drain through the drain tubesof the evaporator housing. After about 20 minutes I open windows to allow fresh air to enter the vehicle. Then I turn on the fan to maximum setting with A/C setting in ON position for approximately 1 minute to dry the system.

Or is it better to start the engine and spray the foam below the window where the outside airflaps of the IHKA units are? see last pic in above link

In this link somebody is using a garden sprayer on an e90 328i, basic idea could also be used for our model https://www.e90post.com/forums/showthread.php?t=1075529 text copied, in the link are pics too: quote
Things I bought:
1) Garden Sprayer.
You can buy any sprayer or reuse the one you already have. I bought 1/2 gallon from the Ace hardware. If you buy - buy the smallest one you can. The space will be limited. Also, buy the one with flexible sprayer hose. You, most likely will need to bend it in different directions as you spray in order to clean as much evaporator surface as possible.
2) Some detergents
I bought lysol and pine sol. Lysol at the picture actually doesn't have nice smell. But I used is since I bought it. I also thought - if I don't like it, bacteria shouln't like it either. I used lysol first, and pine sol next. Still lysol smell remains. So if I did it again, I'd use one more bottle of pine sol after the lysol, or skipped lisol completely. You should, probably, use whatever cleaners you prefer. Not in the pictures, but I used gloves and protective glasses. Do this outside or in well ventilated area.
The hose that goes to the evaporator is behind the glove box, closer to the console, precisely where the blower motor used to be. At the picture you see sprayer's hose inserted in the position ready to spray. Use whatever concentration and total amount you like (water + cleaner) and pressurize the sprayer. I used hot water in a hope for better effect. Lysol I used was of higher concentration than pine sol. Both build some foam as result of spraying. I was afraid this would produce lots of water on the inside, but it only made mess outside the car, and you can reduce that by putting some catch can under the car. Place the sprayer in the foot-well. Put some towel inside the foot-well just in case. Make yourself comfortable, research the hose leading to the evaporator as much as you feel necessary to clearly understand the direction and depth of spraying. Insert sprayer's hose in the direction of the center console. Start spraying just enough to verify the drain hose of the evaporator is not clogged. I did that before, so I had some confidence that the liquid will drain. Still does not hurt to check - look under the car - you should see liquid under the car. If you do not, I wouldn't continue as there's high risk of flooding the inside of the car. I had zero liquid inside the cabin, not even a drop - so all the liquid should drain under the car. From this point on, - just refill and spray in different direction/depth. I let it stay and soak for 5-10 minutes between spraying to let cleaners work on bacteria. It took ~10 minutes to remove the blower and 10 minutes to install it back. The spraying itself took 1.5-2 hours, just because I wanted cleaners to be in contact with the evaporator for more time. As a result there was a lot of liquid under the car. Lots of cleaner smell. I suggest you do it outside or at least put some container under the car to catch water. My car has sport package and is pretty low, so I couldn't find anything suitable to slide in, but for the next time I will buy some kitchen oven pan. I had to water the garage afterwards and still there is still a lot of lysol smell. I've mentioned - the smell is not pleasant, so either use more pine sol after the lysol, or skip lysol completely. By the time I started using pine sol I inspected the water under the car and noticed a lot of white substance and particles in it. Could be deposits of aerosol sprays I used before, or who knows what it was. At the second picture you can see white areas at the floor where cleaners drained. Check if you have any leaks inside the car as you spray. If you notice something - I wouldn't continue as you can cause some shortage. In my case everything was dry inside. After I used both bottles of cleaners I assembled the blower and the panel back in the reverse order. That was easy. Started the car - everything worked - ventilation system, radio and all other systems. I was a little scared to spray this much water in the car, but looks like evaporator case is pretty isolated, which is as it should be as there's lots of moisture there during operation. So I started the car and drove it for some time with fan and heater on. No smell of bacteria and lysol +pine sol smell is much better and natural that of those chemical aerosol sprays I used before. So far so good but I will do this again in a little while just in case. This whole process isn't very difficult and I'd rather repeat it pro-actively than smell bacteria again. unquote

[youngbimmer]

I use lysol by itself through the vents, lavender scented

My mother's C300 suffered from terrible mildew smell when air conditioner was on. I activate fans full blast, recirculate fan off, spray lysol liberally through fresh air vents. I used about half of the can, and it made an absolutely massive improvement, car smelled amazing inside and no more mildew smell. Note: You shouldn't be in the car for sometime after using lysol spray, it can damage your lungs if inhaled in significant quantities.

Procedure could be same for E32: Simply activate AC, maximum blower speed no recirculate fan, and spray lysol through the fresh air vents outside. Do so every 3 months, should keep the IKHA sanitized enough for my purposes.

[shogun]

Today I took the bumper off to check the condenser, all nice clean. Actually the bumper had to come of anyway, as I fixed my aux fan, was not working on high, 1 wire connection for high speed slightly melted = no contact to the aux fan pin.

On the sight glass of the AC (right side engine bay next to the e-box under a black plastic cover) I found some bubbles = R134a a bit low. Filled 1 small can R134a, now again nice cool. Last time I had to refill 1 can was 2 years ago. I converted the system in 2006 from R12 to R134a.

[shogun]

No one else cleans his aircon?
AC filter introduction
all BMW - except E30- produced 09/1991 or later are 100% equipped with the microfilter. All E31 are 100% equipped with 2 filter since their start of the production. BMW with microfilters are supposed a red maintenance reminder decal in the glove compartment. However, on BMW between 9/91 - 5/92 many of the labels were inadvertantly left off. These BMW are - however -equppped with a microfilter - see SI 64 12 92 (3518)

Some vehicle produced prior to 9/91 may be equipped with a microfilter, and can be positively identified by the maintenance reminder decal in the glove box.
Copied from a Service Information circular.

a comment from genphreak to my procedure:
Your approach is the best of those two, and the best I've seen. That pine sol approach risks too much damage. The evaporator fins are aluminium, so the 'product' needs to be non-caustic to it- and also dried as soon as possible once the foaming period finishes.

I'd spray some product onto a piece of mesh once I've finished doing the evaporator. Then once the foam condenses, spray some isopropyl alcohol in through the sensor holes. I'd use a lot too, as that won't rust the car even if it leaks out of the IHKA unit in places.
The reason I would finish with alcohol is because if there is any water left in the system (from the product or otherwise), it will mix with alcohol. This causes the specific gravity of the water to reduce, and thus evaporate very fast.
Here in SE Australia, I've never seen a stinky one yet. Even after 25 years. Dusty though, many fill with dust and particulates- whether they are a problem, who knows. So long as the flow rate of particulates into the cabin air is not increasing once the system collects its threshold amount!

[shogun]

Yesterday we had almost 40 degree Celsius ambient air = 104F here where I live. Drove around with the 750 and noticed that the AC was having a hard time to cool down to comfortable temperatures.
Today I tested, outside temp today about 30 degree C in the shadow = abt 90F, used a contactless thermometer at the center vents, set blower to full speed, AC both sides on lowest possible temperature. Allowed the ac to work a little.
Measured temps out of the center vents abt. 12-14 degree C = abt 57F.
Then I tested the low side freon pressure with a gauge with running engine, it showed normal pressure but on the low side of the 'normal' scale. So I added 1 can of 200 grams R134a, indicator on the pressure gauge had went from low side of normal to just below high side of normal, still in normal, but closer to high.
Tested again with the thermometer, out of the center vents I now get 7-9 degree Celsius, big difference.
Based on an article I read on the net, this is in line with normal function, it says: with an outside temperature of 90F = 32C you would expect a thermometer reading of between 40F-50F = 5-10C in the air conditioning duct. That test was made with the thermometer probe inside the open air vent, I used a contactless thermometer and pointed onto the air vent. So the result is in line with the info in the net and the difference in cooling effect is nice.

I got one of these quick connect checkers, found it some years in the net, not from this co., but same design https://fjcinc.com/product/2805-r-13...erant-checker/

[youngbimmer]

Is it not dangerous to overcharge the AC? Curious where the pressures were at that temperature.

[shogun]

I did not overcharge it, it is still in the 'normal' range at that temperature, there are tables in the net for that with ambient temperatures and the pressures low and high side, example temperature pressure chart https://www.autozone.com/landing/pag...charge-auto-ac
http://rechargeac.com/how-to/ac-system-pressure-chart
to explain it easy, on the typical cheapo R134A Car AC Refrigerant Recharge Hose with Gauge the gauge shows numbers psi/kgcm2, different colors and written Low - Full - Alert - Danger. As you can see here in the example pic the blue color one is the full range and that is from.....to. In my case it was on the low side of normal/blue before recharging, I just added a bit and it is still in the blue range, even not at the border to alert, maybe around 40 https://www.amazon.com/Refrigerant-R...GEQKCSTM7P5BEY
if it is overcharged, it will not work, if it is too low, it will not work, there are pressure switches for low and high as you know. It must be in the correct range.
I have a complete A/C Refrigeration AC Manifold Gauge Set R134A , various gauges, even a vacuum pump.

[youngbimmer]

So you have a leak somewhere...time to go hunting

The heat here in VA has been unbearable. My thermomemter in the shade was reading 100 F, with extremely humid air it was feeling ~110F

[Cactuar]

Very hot and humid in Quebec these days too (feels like 104F). I have to say though that the AC in the E32 is top notch, very cold and works quickly. Much better than the asthmatic system in our Odyssey.

[shogun]

There is a certain normal loss on these old systems, last time I checked it and filled a small volume was about 2 years ago. "Losses of gaseous refrigerant are "normal" and generally accepted by car manufacturers within certain specified limits. "
Report on the Umweltbundesamt (German Federal Environmental Agency) Emission of Refrigerant R-134a from Mobile Air-Conditioning Systems : Overall R-134a emissions are broken down into three types: Normal (bit by bit release through seals), irregular (abrupt, in case of accidents, stone hits etc), disposal emissions (End-of-life sucking out not occurring). Based on 1000 A/C units opened and recorded by 9 garages in 2000 (three different German car makes), the rate of normal loss is assessed at 6.3 % per year (25% tolerance band) over the first seven years of ex work A/C systems use phase. Normal loss is considered any refrigerant deficiency of about 40 % compared to the first fill. The losses below 40 % as recorded by the garages are taken as an unintentional sample survey of the normal emissions. The basic assumption is that a 40 % refrigerant loss still allows the A/C system to work just properly. Irregular losses are all the losses over 40 %. They are mostly caused by external events like accidents, stone hits and suchlike. Therefore the most defective single circuit component to replace is by far the condenser. The rate of irregular emissions amounts to almost 2 % per year (347 kg from all the 21,300 once a year inspected cars equipped with an R-134a ex-work A/C system). Future disposal emissions are estimated at 2 %. This is why the assumed 25 % one-off disposal emissions are split into 12-13 usage years of the A/C system.Thus, the overall emissions range around 10 %/yr. This rate is equivalent to a loss of roughly 88 grams per year and car (average first fill of 0.850 kg). " https://www.oekorecherche.de/de/emis...ioning-systems

Car refrigerant & oil filling quantities, Here you will find useful information and handy tips relating to refrigerant and oil filling quantities for air-conditioning systems in vehicles https://www.hella.com/techworld/uk/T...antities-2114/
E32 with Denso compressor 1525-1575 gr R134a
E32 with Denso compressor with aircon at rear (Highline) 1675-1725 gr R134a
E32 with Seiko compressor 1525-1575 gr R134a
E32 with Seko compressor with aircon at rear (Highline) 1675-1725 gr R134a

[youngbimmer]

Is it possible to source new Seiko compressors from japan? The denso compressors are widely available in the USA, but they do not fit the 735. Seiko compressors are nearly impossible to find.

[shogun]

contact demetk , he makes fitting brackets for Sanden compressors, apparently that is the way to go in the US https://www.bimmerforums.com/forum/s...light=brackets
Pics of how the brackets are used with the sanden 508 and the m30 compressor mount, http://www.mye28.com/viewtopic.php?f=3&t=144670
Seiko parts I never bought in Japan, probably you can buy repair parts easier and cheaper in the US https://www.ackits.com/index.php?route=common/home

[shogun]

Just for info:
airconditioning microfilter introduction Models: all except E30

All vehicles produced 09/1991 or later (except the E30) are equipped 100% with the microfilter.
In addition all E31 vehicles have been equipped 100% with 2 microfilters since their start of production.
Vehicles with the microfilter are supposed to have a red "Maintenance Reminder" decal in the glove compartment.
However, on vehicles produced during 09/1991 - 05/1992, many of the labels were inadvertantly left off.
These vehicles are, however, equipped with a microfilter.
Some vehicles produced prior to 09/1991 may be equipped with a microfilter,and can be positively identified by the presence of the "Maintenance Reminder" decal in the glove compartment.