Thread: Regas with Hychill -30

Originally Posted by Lotz-A-Landies

Davo

You will get much better life out of the York compressor,

Maybe, but a new(ish) Sanden will certainly outlast the current engine and most likely the car...

Originally Posted by rick130

Well for starters you don't need a thermometer in the condenser and evaporator as Dave advocates if you have gauges connected to the system.

There's this funny but basic thing that any refrig/a-c mechanic uses on each job called a pressure/temperature relationship.

Need to have, no, Nice to have yes.

and I usually only goto that much effort when its an "unknown" for a known system, chuck in the base weight minus a little and watch the gauges while you let it slowly suck in the last bit of the nominal weight.

That's a very kind offer Shane, - I'll hold off for a bit till I get the rest of the ducks in a nice neat row.. (Vacuum pump dug out from the bowels of my Shed... new dryer, and gauges)
I tend to price and check every possibility before I make a final decision... and not the least bit Compulsive Disorder-Obsessive....
Besides, there's not that many Classics / D1's over here that would be in need of a re-gas. None of my rellies have one...

Come to think of it, a aquaintance of years ago used a modified fridge compressor as a vacuum pump, and re-charged with LPG. Reckons it worked a treat.
Have no idea what oil he used, or if he changed what was there.

According to the current driver of MY car... the A/C is working "very well, thanks Dad..." Funny, I distinctly recall him commenting on it's inefficiency when I first got her...

Originally Posted by superquag

Maybe, but a new(ish) Sanden will certainly outlast the current engine and most likely the car...

It's got a new engine! And it'll get a new Sanden if all goes well. As for the rest of the car, I'm expecting to battle with it until one of us dies.

Originally Posted by Blknight.aus

Need to have, no, Nice to have yes.

and I usually only goto that much effort when its an "unknown" for a known system, chuck in the base weight minus a little and watch the gauges while you let it slowly suck in the last bit of the nominal weight.

Then how do you measure superheat and subcooling without the Press/temp relationship known?


On another note regarding Evacuation, most of the methods mention will achieve a vacuum of sorts but without a Vac Stat connected you really do not know the true depth of vacuum and if the system is dehyrdrated correctly, just "pulling a Vac" will not remove all the moisture and neither will a new drier. If all these parameters are met you don't need to change the drier, driers are pretty much useless after being open to atmosphere for a short time.


Most modern Air Conditioners do not even require driers, they do have there place though and for clean-ups after burnouts suction driers are important

Originally Posted by Kev the Fridgy

Then how do you measure superheat and subcooling without the Press/temp relationship known?


On another note regarding Evacuation, most of the methods mention will achieve a vacuum of sorts but without a Vac Stat connected you really do not know the true depth of vacuum and if the system is dehyrdrated correctly, just "pulling a Vac" will not remove all the moisture and neither will a new drier. If all these parameters are met you don't need to change the drier, driers are pretty much useless after being open to atmosphere for a short time.


Most modern Air Conditioners do not even require driers, they do have there place though and for clean-ups after burnouts suction driers are important

Exactly,you need a very good 2 stage vacuum pump to pull out any moisture,then you need to break it with high purity nitrogen and then do it again(and maybe a few times more) to get the best results,checking with a vacu stat.Most pumps in service would't pull the skin off a rice pudding,maybe pull a bit of air out,thats it.

i still can't believe these large A/c units have no driers in the system
We have recently had blocked strainers in acurators in a few systems where no driers were fitted.
Sight glasses on the larger ones with TX valves would be good as well.

Cost cutting again......

I'm hearin ya brother

the pressure temp relationship is known. its on the charts and you use your gauges

whats not known is how all of the parts are working together

ever had to do a cars AC that had a crushed pipe in the condensor The whole system works well right up untill you get some good airflow over the condensor and then half of it begins to work as an evaporator, Run it up in the workshop and its fine, get it on the road and the performance deminishes.


thats what all the thermometers do for me, lets me avoid sticking my fat fingers into little spaces near hot engines and spinny bits of death.

unless you're really really cowboying it and running direct lines you're going to have a gauge set on to connect the high and low side for vacing and filling anyway...