Air Con Leak - Low Pressure Side

**willdudeuk** · 20-07-2021,03:29 PM

Got an air con leak on low pressure side..... doesn’t hold vacuum.

any ideas? Going to replace seals first.

condenser was replaced last year with ECP EIS Part (222440611) from memory.

**willdudeuk** · 20-07-2021,04:25 PM

Replaced the following seals and performing another vacuum test.

4E0 260 749 A
3D0 260 749 C
8E0 260 749 C

The 8E0 I removed was damaged so hopefully that was the problem. A small piece was missing from the seal.

561157DD-5709-4022-B9FC-25EFE2DF4732.jpg

**Crasher** · 20-07-2021,05:18 PM

We have trouble with a Golf 5 GTI last week, in the end we found debris from the compressor in the expansion valve, you can store meat in there now it is so cold.

**willdudeuk** · 20-07-2021,05:40 PM

It’s passed the vacuum test and been injected with r134a. It gets cold but not down to 8 degrees centigrade when we use a probe in the dash vents. It’s probably about 11/12 it goes down a bit up one acceleration but doesn’t reach 8.

weak pump?

where is the expansion valve on the Mk5 BAG engine?

If you have any pictures or diagrams that would be great.

thanks

**willdudeuk** · 20-07-2021,07:02 PM

Air con is working.

but still got fault codes on ODIS.

the ECON light / button doesn’t come on when I press it. It’s constantly out the LED. But does appear to turn compressor ON and OFF as the air does go cold and then hot when pressed again.

A/C Compressor Regulator Valve N280
0008- Climate Control Module
898 10 A/C Compressor activation (open circuit / short circuit to B+ Intermittent)

Refrigerant Pressure
0008- Climate Control Module
229 2 Refrigerant Pressure (lower limit not reached - intermittent)

**Crasher** · 20-07-2021,08:29 PM

If it has a Sanden compressor they are very problematic, we insist on Denso new, not recon. The expansion valve is the coupling on the bulkhead to the evaporator. Genuine they are insane money (hundreds) but Febi list them in the tens but have no stock! ECP have Hella for a good price.

**willdudeuk** · 22-05-2022,02:52 PM

Been using the AC for a while now but it’s performance seems to have gone down. Doesn’t appear to be as cold. Must be a refrigerant leak? VCDS is showing 6bar as the refrigerant pressure. Could it be a bad compressor (even though it’s brand new Genuine OEM Denso part?). Or maybe something wrong with the blend flap? Need to check for leaks again and inject with dye and get a UV lamp out again. Hopefully it’s not the condenser or evaporator.

**Crasher** · 23-05-2022,08:53 AM

It needs to be checked on a proper AC system test machine now. I have never had a new Denso fail but it is always possible.

**willdudeuk** · 23-05-2022,02:08 PM

Ok no worries I’ll get it hooked up and see what the Low and High pressures are like. We had no issues vacuuming the system and it holding vacuum. It passed that test otherwise it won’t proceed to injecting gas into system. Perhaps there is an issue when it’s pressurised? Leak somewhere? But seeing as there is still pressure / refrigerant must be ok?

Can the expansion valve have an impact on the cooling performance?

Condenser was replaced as it was the original one and had taken a beating….so may not be that.

**Crasher** · 23-05-2022,05:29 PM

I had the expansion valve on one cause me grief the end of last year, I hardly ever have to replace them. Genuine were daft money but by Febi incredibly cheap.