Vent Temps Unsatisfactory - Page 2 - PeachParts Mercedes-Benz Forum

david s poole · #16 06-18-2007, 10:01 AM

if you can get me gauge readings while at idle and at 1500 rpm i can tell you what is wrong with it.

Arthur Dalton · #17 06-18-2007, 10:21 AM

Quote:

Originally Posted by E150GT

Yes those leads that go on the drier. I do not have any gauge readings.

OK... That is the aux fan sw , but very seldom does that sw go bad..people often incorrectly change it b/c they think it goes bad, but the real reason the fan does not come on is b/c they are short of refrigerant [ not allowing high side to get to trigger point of the sw]
..anyway, gauges would be needed for pressure readings.
Did you use an original R12 EV?
..also, You may have overcharged...

E150GT · #18 06-18-2007, 12:00 PM

I got my 609 cert and bought the R-12 at O'reilleys for 35.99 a can. It took three full cans and som of the fourth. How does this time differ from last time I charged it. A few weeks ago I charged it with only three cans and it blew just as cold or colder than when I put three cans in this time. The only thing thats changed is the expansion valve. could it be bad?

Arthur Dalton · #19 06-18-2007, 12:03 PM

That is why I asked about it being an OEM R12 valve..they make a 134 valve for conversions..

E150GT · #20 06-18-2007, 01:22 PM

The expansion valve did not say r134a on it like the one I pulled out did. i had a post a little earlier on that and somebody here on the forum told me that the expansion valve didn't matter, but I didn't really worry anyway because the new one didnt say R-134a on like the old one.

Arthur Dalton · #21 06-18-2007, 01:53 PM

Well aother possible is you stated you had someone pull a vac and then you added the R12..but..did you check that it held the vac before adding the R12..in that time frame , it may have not held and in that case , you could have air in the system/// but . not enough info to make a diagnosis..

Gauge readings would help.
Do you see comp cut-out??
Is sight glass clear??
Does fan run right off ?
Is suction line sweating??
Have yo check condenser for debries/air flow??
The EV you took out was 134a valve?? Has this car been converted and you just decided to put R12 back in there??

Lots of questions

E150GT · #22 06-18-2007, 03:07 PM

I will try to get gauge readings. ( I need to get gauges)
the compressor does not cutoff.
the aux fan comes on after a few minutes. how many minutes I'm not sure.
There are a few small bubbles in the sight glass, but I,ve had more bubbles and it performed better than this. All lowside lines sweat as well as the expansion valve. even though one side of the ev is warm. Im starting to think i need to have the ac revaccumed. Its just hard to find a good shop that still does r-12 on my schedule. The po is a manager at carlysle auto air and told me when i bought the car that it was still r-12 and it still has the r-12 service fittings, and the new compressor has a factory label stating retrofit to r-134a, but was reconverted to r-12. why it had a r134a expansion valve, I don't know. who knows maybe the a/c is working fine and I'm just bummed because this is the first time ive had the car with a full charge of ref. that didn't leak and it performs worse than it ever has before while I was expecting even better performance.

david s poole · #23 06-18-2007, 06:08 PM

the reason that it said r134 on the valve is that there is no diff between valve for r12 and 134.i went through this back in 1993 and even contacted the manufacturer of the valves.then still being hard headed i ran some tests on same car with two diff valves--no difference at all.

just-n-time · #24 06-18-2007, 06:47 PM

The valves made today are all compatible with both freeze 12 and 134 as well as r12 they will interchange,most companies are reducing the amount of tooling, by making things more interchangeable.