DaytonaBill
Full Access Member
Ha ha! No...
I've got about a week and a half to comprehend this.. Don't worry, I'll get it! Thank's for your patience...
GRRR! I've got black death!
- Thread starter DaytonaBill
- Start date
I've got about a week and a half to comprehend this.. Don't worry, I'll get it! Thank's for your patience...
DaytonaBill
Full Access Member
Yay! I got 6 cans coming next Monday!
Since I have chosen the charging by can method, I thought it would be smart to order more than I need in case I need to 'top off' my system in the future.
I bought three cans of 134a (which I still have to this day) about two and a half years ago and they only cost 99¢ per can. Now they cost $14.99... I expect the ES-12 to do the same... My $3 turned into $45... In two and a half years...
Anyway, I'm getting this new toy to use for checking the inlet and outlet temps of the evaporator when I recharge my system. Using this method is supposed to be the best and easiest way of getting the full amount of refrigerant. I can hardly contain my unbridled enthusiasm!!!
This new toy is a laser thermometer and probably the most accurate way of measuring temps. I would imagine that I would have to wipe the frost off the tubes to use this new toy. At least I'll be able to tell if my wheel bearings are running hot or my vent temp, or my condenser temp difference between the inlet and outlets... Whee!!!
See ya Monday!!!
Since I have chosen the charging by can method, I thought it would be smart to order more than I need in case I need to 'top off' my system in the future.
I bought three cans of 134a (which I still have to this day) about two and a half years ago and they only cost 99¢ per can. Now they cost $14.99... I expect the ES-12 to do the same... My $3 turned into $45... In two and a half years...
Anyway, I'm getting this new toy to use for checking the inlet and outlet temps of the evaporator when I recharge my system. Using this method is supposed to be the best and easiest way of getting the full amount of refrigerant. I can hardly contain my unbridled enthusiasm!!!
This new toy is a laser thermometer and probably the most accurate way of measuring temps. I would imagine that I would have to wipe the frost off the tubes to use this new toy. At least I'll be able to tell if my wheel bearings are running hot or my vent temp, or my condenser temp difference between the inlet and outlets... Whee!!!
See ya Monday!!!
itsacrazyasian
residentcrazyasian
POINT AND SHOOT THERMETER IS PRICELSS WHEN DOING AC WORK. SORRY FOR CAPS, IF YOU COULD SEE MY LAPTOP GHETTO RIGGED YOUD LUAGH BUT ITS THE ONLY WAY FOR ME TO GET MY OB FIC
DaytonaBill
Full Access Member
This one is different, but I'll be able to put the IR sensor right against the tubes... 
Good from -58° F to 1112° F...
Good from -58° F to 1112° F...
You must be registered for see images attach
DaytonaBill
Full Access Member
Ok, I finally got the A/C cooling again...
I may have over charged it just a little...
In 73°, 58% humidity ambient air, my A/C vent temps are 45°, driving at 40 MPH, for a total of 5 miles.
My pressure stats at 1400 RPMS are as follows;
All of the temp readings were taken with that IR thermometer with the flexible head... I think the thermometer gives inaccurate readings... and there is no way to field calibrate the thing...
I think I'm going to retake the temps of both sides of the evaporator with a stick thermometer, similar to a meat thermometer...
BTW, is the compressor supposed to be cold enough to sweat? The back half, anyway?
I'll repost as soon as I get those numbers...
On another note, I wonder if my ranch hand bumper is deflecting the airflow to the condenser... I have sealed the bottom and sides with 2.5" foam insulation, so the fan should be doing a good job with airflow through the condenser...
I'm just trying to figure out why the vent temps are not freezing even though the IR thermometer indicates that the temps in the evaporator is between 15° and 25° with the air flowing through the evaporator core @ 70° with 35% humidity, with the vent temps reading 45°... I want the vent temps at 32° when it's 82° outside. I'm aiming for 50° at the vents on a 100° day, for a fifty degree drop... Or is that just a pipe dream?
Anyway, I'll get more readings with the stick thermometer and repost those numbers...
C-ya!
I may have over charged it just a little...
In 73°, 58% humidity ambient air, my A/C vent temps are 45°, driving at 40 MPH, for a total of 5 miles.
My pressure stats at 1400 RPMS are as follows;
- Ambient temp @ 1" from face of condenser = 83°
- Condenser inlet = 141°
- Condenser outlet = 95°
- Evaporator inlet = 15°
- Evaporator outlet = 25°
- Suction Hose at Accumulator = 18°
- Suction Hose at Compressor = 16°
- Cycle Switch set at 30 PSI
- High Side = 190 PSI
- Ten minutes after shut off = 98 PSI equalized @ 75° in shade
All of the temp readings were taken with that IR thermometer with the flexible head... I think the thermometer gives inaccurate readings... and there is no way to field calibrate the thing...
I think I'm going to retake the temps of both sides of the evaporator with a stick thermometer, similar to a meat thermometer...
BTW, is the compressor supposed to be cold enough to sweat? The back half, anyway?
I'll repost as soon as I get those numbers...
On another note, I wonder if my ranch hand bumper is deflecting the airflow to the condenser... I have sealed the bottom and sides with 2.5" foam insulation, so the fan should be doing a good job with airflow through the condenser...
I'm just trying to figure out why the vent temps are not freezing even though the IR thermometer indicates that the temps in the evaporator is between 15° and 25° with the air flowing through the evaporator core @ 70° with 35% humidity, with the vent temps reading 45°... I want the vent temps at 32° when it's 82° outside. I'm aiming for 50° at the vents on a 100° day, for a fifty degree drop... Or is that just a pipe dream?
Anyway, I'll get more readings with the stick thermometer and repost those numbers...
C-ya!
Last edited:
itsacrazyasian
residentcrazyasian
you have a heater core shut off?
DaytonaBill
Full Access Member
Well, that was a failed experiment... Stick thermometers don't work... Even if you wrap the pipe with foam insulation for the purpose of deflecting the hot air from the exposed stem... Then I tried a thermocouple from one of those indoor-outdoor digital thermometers... I shoved the thermocouple into the space between the pipe insulation and the tube just before it goes to the accumulator, where the low side pressure readings are taken....
@ 30 PSI, the temp should have been 18°, according to the P/T chart for the refrigerant I'm using... With the thermocouple, I got 55°... Stuffed into the tight space between the tube and the inside of the pipe insulation... Argg... How can the vent temp be 45° when the temp measured by this thermocouple says 55°?
Ok, let's summarize... The evaporator inlet tube is slightly icing up just past the orifice tube...And that's with the cycle switch set to cycle off at 30 PSI.
With the IR thermometer at the evaporator outlet, before it goes into the accumulator, the temp is 25°, but not frosting up...
For what it's worth, the IR thermometer, when taking temp reading at wall thermostat in house, reads 65° when the wall thermostat reads 74° and it's digital...
So, if the IR thermometer is 9° colder than actual reading, then that means those temp readings I gave earlier needs to be corrected by adding 9°...
That sounds about right... But the low-side pressure reading is taken at the evap outlet. I recorded 30 PSI and the corrected temp would be 34°... But it's supposed to be 18° at that pressure...
Either my gauges are off, or the Pressure/Temperature Chart for this refrigerant is wrong... Here is the P/T chart.
I tried to do everything by the numbers and something is whacked badly... Very frustrating... I'd appreciate anybody's thoughts, if they can see where this went wrong...
I know that some air in the system would result in diluted charge and skew the P/T relationship, but when I charged this sucker up the first time, I did so from a hard vacuum that held for one hour and then I hooked the charging hose to the first can and purged the hose with the can upside down, so that liquid would purge out and there would be no air in the hose.
I had left the hose adapters that enables me to hook my R-132a gauges to the R-12 connections and it leaked overnight. When I discovered that it leaked some of the charge (it still had 35 PSI @ 70°) I made sure I thoroughly purged the charging (yellow) and the low-side hoses before I allowed the charge to enter the system.
Anyway, I said all of that to show that there can't be any air in the system. It still had 35 PSI and I purged the hoses... Ergo, no air...
I see Itsacrazyasian is here... Yeah, I installed a ball valve set up to divert the hot water away from the heater core... And it's diverting... Do you suppose that, no, there's no way ball valves can leak that soon... It's only two years old...
@ 30 PSI, the temp should have been 18°, according to the P/T chart for the refrigerant I'm using... With the thermocouple, I got 55°... Stuffed into the tight space between the tube and the inside of the pipe insulation... Argg... How can the vent temp be 45° when the temp measured by this thermocouple says 55°?
Ok, let's summarize... The evaporator inlet tube is slightly icing up just past the orifice tube...And that's with the cycle switch set to cycle off at 30 PSI.
With the IR thermometer at the evaporator outlet, before it goes into the accumulator, the temp is 25°, but not frosting up...
For what it's worth, the IR thermometer, when taking temp reading at wall thermostat in house, reads 65° when the wall thermostat reads 74° and it's digital...
So, if the IR thermometer is 9° colder than actual reading, then that means those temp readings I gave earlier needs to be corrected by adding 9°...
That sounds about right... But the low-side pressure reading is taken at the evap outlet. I recorded 30 PSI and the corrected temp would be 34°... But it's supposed to be 18° at that pressure...
Either my gauges are off, or the Pressure/Temperature Chart for this refrigerant is wrong... Here is the P/T chart.
You must be registered for see images attach
This does not compute... How can you get 34° @ 30PSI, when it's supposed to be 18°?I tried to do everything by the numbers and something is whacked badly... Very frustrating... I'd appreciate anybody's thoughts, if they can see where this went wrong...
I know that some air in the system would result in diluted charge and skew the P/T relationship, but when I charged this sucker up the first time, I did so from a hard vacuum that held for one hour and then I hooked the charging hose to the first can and purged the hose with the can upside down, so that liquid would purge out and there would be no air in the hose.
I had left the hose adapters that enables me to hook my R-132a gauges to the R-12 connections and it leaked overnight. When I discovered that it leaked some of the charge (it still had 35 PSI @ 70°) I made sure I thoroughly purged the charging (yellow) and the low-side hoses before I allowed the charge to enter the system.
Anyway, I said all of that to show that there can't be any air in the system. It still had 35 PSI and I purged the hoses... Ergo, no air...
I see Itsacrazyasian is here... Yeah, I installed a ball valve set up to divert the hot water away from the heater core... And it's diverting... Do you suppose that, no, there's no way ball valves can leak that soon... It's only two years old...
Last edited:
DaytonaBill
Full Access Member
You know what? Now I wonder about the ball valves... I'm going to go for a drive with just the vent on and see what the temp to that is...
Back soon...
Back soon...
itsacrazyasian
residentcrazyasian
its been a very long day for me, i'll check the pressures on my truck tommorow. Actually i need to remind myself to check my oil tomorrow too. Right now i gotta tend to a sedated cat.
itsacrazyasian
residentcrazyasian
where were you measuring the 55F temp?
DaytonaBill
Full Access Member
Well, the heater core bypass is working and the air box is insulated well enough to register a 3° rise with the heat on at low fan speed...
So that's not it...
So that's not it...
DaytonaBill
Full Access Member
On the tube that comes out of the accumulator, between the can and the threaded connection to the suction hose... I measured 18° at that same spot with the IR thermometer, so being 9° colder than actual, that would be 27°...
Are you thinking that the thermocouple to the indoor-outdoor thermometer is more accurate than the IR thermometer?
Thanks for your help and good luck with the sedated cat...
boxathey
Full Access Member
The normal rule of thumb is 35 degree drop from ambient temperature. you can make it more by recirculating the cab air and not bring in outside air. The suction side of compressor and accumulator does sweat on humid days
DaytonaBill
Full Access Member
I haven't gotten around to fixing the vacuum hose that goes to the recirculation door, so I've got the vacuum motor disengaged from the door and the door propped closed...
So what do you think of the running pressures and the P/T Chart for the refrigerant I'm using?
There's a few things that could be the problem...
One, crappy new compressor... Two, impure refrigerant... Three, improper P/T Chart... Four, not enough sub cooling across the condenser from air deflection due to the huge bumper...Click on picture for a clear view of the screen across the front...
Five, air in the line, highly doubtful...
Using Occam's Razor, I would say improper charge... Bumper grill deflecting too much air, or crappy new compressor. In that order...
From now on, I'm buying either Visteon or Hella... I wish I had a machine shop, I would see about sleeving all ten cylinders and getting good quality pistons... I'd also surface treat the swashplate with a friction resistive coating and see if the valves could seal better. In other words, blueprint my own compressor and make it longer lasting and pump more efficiently...
So what do you think of the running pressures and the P/T Chart for the refrigerant I'm using?
There's a few things that could be the problem...
One, crappy new compressor... Two, impure refrigerant... Three, improper P/T Chart... Four, not enough sub cooling across the condenser from air deflection due to the huge bumper...Click on picture for a clear view of the screen across the front...
You must be registered for see images attach
Five, air in the line, highly doubtful...
Using Occam's Razor, I would say improper charge... Bumper grill deflecting too much air, or crappy new compressor. In that order...
From now on, I'm buying either Visteon or Hella... I wish I had a machine shop, I would see about sleeving all ten cylinders and getting good quality pistons... I'd also surface treat the swashplate with a friction resistive coating and see if the valves could seal better. In other words, blueprint my own compressor and make it longer lasting and pump more efficiently...
Last edited:
DaytonaBill
Full Access Member
Well, it was definitely over charged...
Before, I got the same temp (49°-50°) at all fan speeds (I think the evap was getting flooded) and today, after 'farting' eight seconds worth of gas several times, the lower the fan speed, the lower the temps drop... I've been able to shave 7° off the vent temps...
Still have to continue until it stops going down and then I'll add just a little fart's worth of gas...
I'm down to 42° vent temp @ 78° for a 36° drop from ambient temp...
At least I know which way to go and when I can go no further, then it's time to add a fan to the condenser.
I sure hope I can hit 32° at 82° ambient temp... That way, I should have 50° vent temps @ 100° ambient temp. That's the way it works, right?
I'll be happy with those numbers as I like to be able to use the A/C when it's in the mid 80's and have no need for A/C below that... It would freeze up anyway if I used it below 82° with a 50° drop... Theoretically anyway...
Will continue to 'fart' gas first chance tomorrow. I think I'm still flooding the evap a little... I can see the temp stay steady and then all of a sudden, I get a 2 or 3 degree rise in temp. That's evap flooding, right? I'm sure glad I was using a propane blend... I think that if I had overcharged it this much with R-134a, the compressor would have been slugged to death from liquid refrigerant. What saved me is the fact that this refrigerant has a lower boiling point than R-134a, so by the time it reached the compressor, it boiled all away...
C-ya!
Before, I got the same temp (49°-50°) at all fan speeds (I think the evap was getting flooded) and today, after 'farting' eight seconds worth of gas several times, the lower the fan speed, the lower the temps drop... I've been able to shave 7° off the vent temps...
Still have to continue until it stops going down and then I'll add just a little fart's worth of gas...
I'm down to 42° vent temp @ 78° for a 36° drop from ambient temp...
At least I know which way to go and when I can go no further, then it's time to add a fan to the condenser.
I sure hope I can hit 32° at 82° ambient temp... That way, I should have 50° vent temps @ 100° ambient temp. That's the way it works, right?
I'll be happy with those numbers as I like to be able to use the A/C when it's in the mid 80's and have no need for A/C below that... It would freeze up anyway if I used it below 82° with a 50° drop... Theoretically anyway...
Will continue to 'fart' gas first chance tomorrow. I think I'm still flooding the evap a little... I can see the temp stay steady and then all of a sudden, I get a 2 or 3 degree rise in temp. That's evap flooding, right? I'm sure glad I was using a propane blend... I think that if I had overcharged it this much with R-134a, the compressor would have been slugged to death from liquid refrigerant. What saved me is the fact that this refrigerant has a lower boiling point than R-134a, so by the time it reached the compressor, it boiled all away...
C-ya!
