Wrong Size AC hose
Wrong Size AC hose I have a 1971 Pontiac Grand Safari, (b-body). Several years ago I had to have a new AC hose made. The one that goes from the back of the compressor to the condenser. This is the high side. I just noticed that this hose is the same diameter as the one from the evaporator to the compressor, which is the low side. I think this means that my hose was made too big (too large in diameter) and I'm just now noticing.
What issues would this potentially cause? The car hasn't been driven in several years so the new hose hasn't been tested.
What issues would this potentially cause? The car hasn't been driven in several years so the new hose hasn't been tested.
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Joined: Jun 2016
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From: Central Cal.
As long as the connections are good, it should not be an issue. Aftermarket installs used to use the same size hose on both sides all the time.
The factory uses 2 sizes because under higher pressure, the high side doesn't NEED the bigger hose. They saved on not using larger diameter hose on the high side.
Both sizes are rated at the same pressure, so it won't be an issue.
The factory uses 2 sizes because under higher pressure, the high side doesn't NEED the bigger hose. They saved on not using larger diameter hose on the high side.
Both sizes are rated at the same pressure, so it won't be an issue.
It's application specific
In most aftermarket systems, there are 3 sizes
#10 Evap core to compressor, #8 compressor to condenser, #6 condenser to Evap core
Factory and halfway systems can be a myriad of sizes from #6 to #12 and do not always follow the three common sizes above
EX: Most factory systems utilize a orifice tube filter which is too big to fit in a #6 line. Factory cars flare up to #8 for the section and back down to #6 for the rest of the run. Often times this leads to #6 or #8 ends at the condenser or evap core, wherever the filter ends up fitting. Also, most factory evap cores dump right into driers which are often #12 in/out and reduce to #10 line. Aftermarket systems typically put the drier in the #6 line near the condenser
I'd wager you're adapting to a factory evap that has a R134 conversion adding a #8 orifice tube to the #6 liquid line. So you're seeing a #8 fitting near the AC box, where #8 is typically compressor to condenser. It's normal to see the #6 line terminated with a #8 fitting. It could be the #6 line was entirely omitted and #8 used in it's place
Probably not super helpful for this build, but for future people searching, here's a good site to find the step up ends
https://coldhose.com/collections/female-oring
In most aftermarket systems, there are 3 sizes
#10 Evap core to compressor, #8 compressor to condenser, #6 condenser to Evap core
Factory and halfway systems can be a myriad of sizes from #6 to #12 and do not always follow the three common sizes above
EX: Most factory systems utilize a orifice tube filter which is too big to fit in a #6 line. Factory cars flare up to #8 for the section and back down to #6 for the rest of the run. Often times this leads to #6 or #8 ends at the condenser or evap core, wherever the filter ends up fitting. Also, most factory evap cores dump right into driers which are often #12 in/out and reduce to #10 line. Aftermarket systems typically put the drier in the #6 line near the condenser
I'd wager you're adapting to a factory evap that has a R134 conversion adding a #8 orifice tube to the #6 liquid line. So you're seeing a #8 fitting near the AC box, where #8 is typically compressor to condenser. It's normal to see the #6 line terminated with a #8 fitting. It could be the #6 line was entirely omitted and #8 used in it's place
Probably not super helpful for this build, but for future people searching, here's a good site to find the step up ends
https://coldhose.com/collections/female-oring
For 71, there was no orifice tube, it was a POA valve. This is the hose between the compressor and condenser, which doesn't have any fittings or filters, but I am going to be adding a trinary switch.
I'm going through this right now. I'm trying to add a pressure sensor to my high side line between the compressor and condenser. I cut the rubber, or flexible section, of line to install an in-line splice with M10 port, and reduced barrier hose...... long story short the inside diameter measures .465"... between an 8 and a 10. The #10 splice I could not force the hose onto it. The #8 was so loose I did not think it would crimp and seal. I ended up buying aluminum solid rod and having to make my own splice.. what a freaking pain. Cold hose cust service was.....of little support. Why this hose was such a weird diameter... I have no clue.. but I got it fixed. Those of you without lathes, or a TIG welder... I wish you the best.. trying to figure out the sizing, and terminology, and then realizing what you are working with matches NOTHING you are reading about.... can be stressful.
