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What I want to say is , for mine and maybe specific to the firmware I have...which I do not know how to check, no menu for it ... there are ways the unit will freeze.
If it does freeze, there is a small RESET button at the back.
It will guaranteed to freeze if you are in video recording mode, and yours is a dual lens mode like mine* ( * a 5.5mm / 0.21" with 3 meters/ 9.8 feet probe ) , you then keep switching between
front and side view a few times. The processor seems weak.
If not in video recording mode, only display mode or photo mode, so far so good and no freeze.
Overall I am impressed for its video quality and the lens which is not so bad as in not so blurry when objects are much far away from the lens.
I got low cost USB based inspection camera and once 10+ cm away, basically it you are blind due to super blur.
Some shots of my evaporator coil as sample for its side camera image quality.
Thats a good tip Cali !! , that pre-filter thingy.
This Teslong if it weren't for its 90 degrees side camera, it would not be as cool as it is.
A real professional unit with articulating probe head cost A LOT
Since the probe is not easy to spin because it is stiff, albeit easy to push because it is stiff, I think if I were to make a simple "T" handle suitable for evaporator work,,, this baby camera can then be aimed/spinned much easier.
While on A/C talk, I got these 2 guides from NISSEN worth looking at. PDF, attached.
I am beginning to understand ( so very slowly ) the pressure temperature relationship of the refrigerant.
That means when I am ready, I can start investigating if my A/C system current performance is as good as it can be.
There is no denying that pumping a compressed refrigerant through a TXV works. When it evaporates it picks up heat in thst process.
The interesting question is how to simply push the limits within a $5 budget.
There is a good answer: decrease the loses to boost efficiency.
SAFETY WISE:
beware of working around pressurized "freon" ref-gases:
wear glasses and gloves when needed.
Do NOT disturb A/C pipes and fittings unless you really have to!
hot compressor >
front condenser >
hot pressure side heat-exchanger>
TXV aperture >
cabin evaporator coil >
cold low pressure side heat-exchanger>
compressor>
JAKARTA SUPER A/C:
In your 100% tropical climate you can wrap every A/C pipe under the hot engine hood to prevent bad parasitic heat transfers, *EXCEPT* the hot pipe between compressor to front condenser. Everything after condenser wrap - (It will prevent hot engine heat from impacting pressures).
Feel free to watch many youtube videos about car A/C how to help you get cooler faster for cheap.
Your system coils are clean and working fine, now simply wrap couple pipe sections and watch... the difference will be obvious in 10mn without any instrumentation temp measures...
Steady freezing cold air for $5 🙂
Colorful graph showing the refrigerant exiting condenser around 140F and cooling down to enter "dryer" (not on Benz) around 122F... PRACTICALLY NOT TRUE in cars!
When the high-pressure line is not wrapped, it REHEATS to ABOVE 230F by heat transfer from the really hot engine in summer.
We should keep that line as "cooled" as it got up-front - Don't let it pick up any engine heat ✌️
Imagine when your condenser is dirty or when you are stopped in traffic, the cooling inside sucks because refrigerant stays hot all around....
It's obvious once you know.
😅 super simple: limit heat transfers
Last edited by CaliBenzDriver; 05-10-2021 at 04:25 AM.
Nice info . Will experiment on HVAC next round.
I wish my bumper is easy to remove like non AMG bumper/griller combo. That way I can experiment much easier.
I have not even fix the whistling sound yet
Let's warm up the conversation.
By next week, Indonesia business will be open as normal.
Since 12th May it was the Moslem super long holiday after fasting, so many business closed for 1-2 weeks.
The W212 drier is built in at the condensor, that long tube thingy on the side, hence you reminded me :
Cali wrote on 10th May 2021 :
Colorful graph showing the refrigerant exiting condenser around 140F and cooling down to enter "dryer" (not on Benz) around 122F... PRACTICALLY NOT TRUE in cars!
When the high-pressure line is not wrapped, it REHEATS to ABOVE 230F by heat transfer from the really hot engine in summer.
We should keep that line as "cooled" as it got up-front - Don't let it pick up any engine heat ✌️
I want to learn more about HVAC. I am thinking to buy the dual gauge manifold for HVAC works. I already have vacuum pump for my diving toys and it is big, big enough for HVAC work.
I do not intend to evacuate my freon or something like that...no no no.
All I want is to confirm first is : what freon pressure vs temperature is going on in my HVAC systen.
I would probaby also invest in another dual channel thermocouple unit. I want to log my evaporator metal temperature if I can.
I will mess with my iCarsoft MB v2 scanner, see if it has any data I can use. I never really explore its capability other than clearing codes and looking at transmission oil temperature.
You'll find the HVAC module exposes pretty good live data including pressure, temps, clutch on/off...
Leave your shredder valvesundisturbed!
I recommend against plugging a gauge-set because on old valves will start to slow-leak once unseated. You can learn to reseat them but ultimately that will lead you into replacing valves with a special extraction tool - I think it's still best not to open that can of worms unless you want to customize your refrigeramt charge - that could be very interesting too... besides pipe wrapping.
Insulating your AC pipes is a quick trick with amazing instant results... Recently I found Youtube channel showing it for unrelated cars and trucks.
Last edited by CaliBenzDriver; 05-17-2021 at 12:37 PM.
So I tested my A/C system. Stationary, no direct sunlight. Ambient temp 32C.
At approx 11 ish minutes into timecode ( A/C activation duration) I open the hood to measure thermal readings.
Total test time 29.x minutes.
Little did I know when I was rigging cameras to log, that shooting the dashboard for coolant temp and RPM is useless hahahah, iCarsoft MB v2 has those data available under Climate Control menu.
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The thermocouple wire below, T2, is hanging and not touching the carpet or anything and is approx halfway to the firewall. Approx just below the hinge of the glove box, approx.
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So pressure shown is the High Pressure one, if using the manual capillary gauge.
==== ALL THERMAL IMAGING BELOW IS APPROX 1 to 5 MINUTES AFTER MINUTES 11:15 OF TIME CODE, and not accurate to the shown Time Code of the screen captures =====
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Expect accuracy of +-2 to 3C for thermal imaging if shooting shiny pipes/object/color.
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Above is compressor output hose/pipe from compressor to condensor.
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I do not know if the data from outside air temperature sensor is calculated to the A/C algo or not and if extra 8C false/radiation heat can throttle down my A/C ?
I intend to also shield the sensor inside part ( at engine bay ) fom excessive engine heat, aside from the targeted freon pipes/hoses.
Next test I want to spray water to the outside air temp sensor and cool it down to actual ambient air temp, see how the A/C algo wil react .
I will choose thickness of the foam wall to be 25mm ( 1") , that is the thickest the online seller has, albeit Thailand has up to 50mm thick..WOW !!
Below is ID 1" (25mm) and wall thickness 25mm. 2 meters, +-US$6.80 only https://www.tokopedia.com/globalpipa...-25mm-aeroflex
I can do with 3 sizes for the ID. 1" (25mm) , 3/4" ( 19mm) and 1/2" ( 12.7mm). Seller sell per 2 meters.
The A/C pipes insulation delivers most noticeable delta when the system reaches its limits:
-- 100F high heat day
-- idle rpm in stopped traffic
-- car up front blowing hot air
The difference is evap. temp won't go up. It'll stay low, coping well with the heat load
vs. inside temperature shoot up when high pressure line gets toasty hot.
Under mild conditions (temps, speed, rpm) A/C works well due to Benz nice heat exchanger able to cool the hot pressure line. Adding insulation simply helps maintain these favorable conditions by reducing engine heat picked up on the way to evap. coil.
The goal is to only pick up more cabin heat by reducing heat transfers from sizzling engine bay -
sweaty suction side
The water condensation sweating over the return pipe shows that in these conditions, the refrigerant can still absorb more heat even after the heat exchanger... it's nowhere near limits. Around limits everything gets toasty including the driver!
Last edited by CaliBenzDriver; 05-18-2021 at 10:13 PM.
Reason: sweaty pipe
heat exchanger implies pipes ARE heat sensitive !!
Originally Posted by pierrejoliat
I wonder how many degrees you can lower the vent temps by wrapping just those two lines? Interesting.
I'd say a good deal but it depends what outside temps are. Below 85F ambient not much difference.
What you'll notice is inside temps get lower faster and stay lower regardless of traffic conditions because engine heat won't get back into liquid refrigerant.
Benz engineers have carved two nice cooler zones on each side of the main engine bay for sensitive components: heat-exchanger, main battery, master cylinder, SAM
The heat exchanger was my 1st tip to figure pipes are heat sensitive and to keep things wrapped is best.
Insulating gas line could well be beneficial for our high pressure pump...
I wonder how many degrees you can lower the vent temps by wrapping just those two lines? Interesting.
I was experimenting with the T2 sensor position in to the vent.
If I place it deeper by 5-7 cm, it reads cooler by 0.5C , as the cool air has shorter distance from the evap and has absorbed less ambient heat.
Yes, I'm somewhat familiar as I run industrial chillers, but, I'd like to see a vent outlet drop by wrapping the pipes, as to what it might be, I also wrap steam lines for the opposite reasons.
Yes, me curious too on what kind of improvement I can get by wrapping the 2 pipes.
I need to create a proper baseline first, before I insulate the pipes, so that improvement can be gauged..
Experiment update.
Below is the baseline test. CAR IS STATIONARY. NO INSULATION YET. In the morning 9:30 AM ish and has rather strong sunlight. Supposedly 30C ambient.
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On purpose I use 2 sensors at SUCTION LINE. The right side display.
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I was raising RPM to approx 1,000 for 1 minute, just for curiosity sake
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The time code for OFF based on A/C COMPRESSOR been OFF that long, not the engine. I killed the engine a few minutes after Air-Cond Comp. I was running blower only for 2ish minutes after compressor OFF.
No, engine hood closed all the time. It is the position of the engine bay ambient temp sensor, which it actually reads the heat removal of radiator+condensor and not engine block + turbo heat radiation.
You will see in a few more minutes my MOVING TEST, 85C is possible.
When HVAC test done, I have always wanted to read how hot is the air above the turbo heat shield. Now that I got 4 thermocouples I can use, there will be more "THERMAL" test coming .... he he he.
This cruise/ride is about 5-7 minutes after stationary test. So things are still hot at engine bay.
Please note the difference between stationary test and moving test is the stationary one I blast maximum blower speed, where moving one I step down blower speed 2 level from Max.
It is too noisy and and not comfy for me when driving with maximum blower speed blasting me.
Also due to the sun position higher as the morning progress and car can be 100% sun-shined compared to stationary where partially sunlight still blocked by a tree, 2C higher temperature
is what I got as car's ambient temperature at left foot-well.
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Engine bay temperature can be as high as 85C in the moving test after de-acceleration. Well, more heat produced or better explanation is more heat removed from radiator and it blows the
hotter air to T2 of left side unit.
The moving test is split into 2 purpose. First half is the HVAC test and the last half is the charging test to see improvement from the beefed-up grounding.
I can't hook up my OBD2 Torque App bluetooth dongle at the same time with iCarsoft MB V2.0, it will lag big time. I tried once, so no go.
Below is the video, 6 minutes of HVAC test portion while moving/cruise.
I notice at higher car speed suction line at compressor T1 right side display will have 9C temperature increase.
I think the temp sensor proximity to the compressor itself is why it can read hotter temp.
See timecode 11:34.xxx to 12:36.xxx
05-08-2021 | 01:48 AM
... there are ways the unit will freeze.
, that pre-filter thingy.
) the pressure temperature relationship of the refrigerant. 
heat exchanger implies pipes ARE heat sensitive !!
