Hard lines for A/C

[jakekooser]

Going to start this by saying I live in South Florida, so it's ALWAYS air conditioning season.

Predictably, the A/C on my '86 Carrera isn't great. I don't mind driving around with the windows down, but the reality is that actual summertime is coming and I have a black car.

I gather that at a minimum I should be looking to replace my hoses with barrier hose, but I wondered why I haven't seen anyone replacing the longest length of the hoses to the front condensor with hard lines, like the mirror image of ER oil lines.

Anyone?

Not looking to start another A/C controversy thread, just genuinely curious.

[wwest]

Simple...

Getting "hosed" is a lot less expensive.

In the alternative,... As a minimum....

Convert the system to R-134a.

Install a Red Dot trinary pressure switch that will limit the maximum system pressure to 325 PSI, no overpressures to help non-barrier hose leaking.

Wire the Red Dot fan/shutter pressure control switch between chassis ground and the engine oil temperature sensing input to the cabin heater blower control module.

The acknowledged, widely acknowledged, single major shortcoming of the 911 factory A/C system is the lack of adequate condensing efficiency in low speed stop and go traffic, HOT climates and consistently low engine RPM.

With this modification in place the rear lid condenser cooling airflow will be in the range of 150-175 FPM vs 50-70 FPM without. More than doubling the factory refrigerant condensing efficiency at the specific time/conditions efficiency enhancement is most meaningful.

[SilberUrS6]

Originally Posted by jakekooser

Going to start this by saying I live in South Florida, so it's ALWAYS air conditioning season.

Predictably, the A/C on my '86 Carrera isn't great. I don't mind driving around with the windows down, but the reality is that actual summertime is coming and I have a black car.

I gather that at a minimum I should be looking to replace my hoses with barrier hose, but I wondered why I haven't seen anyone replacing the longest length of the hoses to the front condensor with hard lines, like the mirror image of ER oil lines.

Anyone?

Not looking to start another A/C controversy thread, just genuinely curious.

Yeah, well, any AC thread will have wwest spewing his same tripe. Best to just ignore him. I have also wondered this - all those long runs could use hard lines. But there must be a reason for it. I think that part of the reason is that there needs to be flex at either end of the run. So, that means hose. Well, instead of two connections per run, you'll now have four. And stuff is more likely to leak at a connection. Double the connections, double the potential for leaking.

[aschen]

its hard enough to get the lines routed as hoses, hard lines would be great but I think nearly impossible to install without complete dissassembly of the car

[billybek]

I would guess that adding hard lines will add 4 more connections as you would need to transition from hard line to flex to the component connection for vibration resistance.
4 more connections on a system that already looks like an old school piping screensaver is probably not a good thing.
There would be less resistance per foot of run but would be another target for the uninformed putting the car on a lift.
The suction hard line would need to be insulated so as not to add more heat that is not doing any work in the system.

[GH85Carrera]

Swapping the hoses to barrier hoses is the hardest and dirtiest part of the entire AC upgrade path. I just went with Griffith's package and all the hoses were the perfect length and fit. After many years there are still no leaks at all.

You can indeed just take the old hoses off and take them to a local AC shop to have the rubber hoses replaced with barrier hose. They can reuse the ends. That would be more of a challenge to do labor wise.

[stormcrow]

I replaced my refrigerant line from the rear condenser to the front condenser with copper. Been like that for at least 6 years now and haven't had a problem. It's been awhile since I did mine but I believe I used 3/8 or 7/16 copper - flared both ends.

Cut the hose on the rear condensing unit, put a flare adapter in the hose and connected the tubing to it. The connection at the condenser on the front is made for a flare fitting. Also ran copper from the front condenser to the expansion valve.

Got to use soft copper though.