Many people think that a gauge set is a single low side gauge, connected to
a low side coupler and a can tap. If you have Lady Luck on your side, once
your system stops cooling, the low side pressure will be about ten, but
there will be enough refrigerant to actuate the switch that keeps the
compressor engaged. After a 13 oz. can of refrigerant it will start working
again, with a low side pressure of 25-30. This is hardly scientific, in
that you have little chance of getting the precise amount of refrigerant
that R134a systems like to have. It is even less scientific, than
attempting to charge an R134a system using high and low side gauges.

As another poster points out, if the system "accidentally" discharges
itself, you will now have the opportunity to install the correct amount of
refrigerant.

Earle

"philthy" <dbrider@cac.net> wrote in message
news:448F78CC.17379A94@cac.net...
> the main thing you left out was what the gauge set was reading as far as
> pressures in the ac system are. do you have one ?? so you can hook it up
and
> tell us what they are??? knowing what high side and low side pressures
are, goes
> a long way in telling what is wrong with a ac system and avoids extra work
also
> include ambaint temp at the time
>
> Diezmon wrote:
>
> > Hey all,
> >
> > I've been reading the MANY posts and sites about TJ's and air
conditioning
> > problems, but didn't find a definite answer to my symptoms. I hope to
hell
> > it's not the evaporator.
> >
> > So, here's the deal:
> >
> > -compressor is working normally
> > -blower fan is working normally
> > -air dampers appear to be working normally
> > -tube from compressor to condenser is hot
> > -tube from condenser into firewall/evaporator is nice and cold
> > -tube OUT from firewall/evaporator is warm.. like air temperature warm.
( I
> > would assume this would be fairly cool as well, since the evaporator
> > probably isn't 100% efficient? )
> > -airflow inside the cabin is KIND of cool, but definitely not cold..
hard to
> > tell if it's just air temp, but it may feel cooler just because of the
rapid
> > air flow..
> > -hot/cold selector seems to be working fine.. definitely HOT air when
> > switched to hot.
> >
> > I took most of the dash off, to see the cables, dampers etc, and to see
if
> > there's some kind of physical blockage in there.. nothing obvious.
> >
> > Before I completely take out the heater/ac housing, do these symptoms
tell
> > you anything concrete about the evaporator?
> >
> > Thanks!
> >
> > Tim
> >
> > Yikes ==> http://www.diezfamily.us/coppermine/...s.php?album=34
>



--
Posted via a free Usenet account from http://www.teranews.com

 

On Mon, 12 Jun 2006 16:19:23 -0500, "Diezmon"
<notmyrealemail@fakeemail.com> wrote:

>Hey all,
>
>I've been reading the MANY posts and sites about TJ's and air conditioning
>problems, but didn't find a definite answer to my symptoms. I hope to hell
>it's not the evaporator.
>
>So, here's the deal:
>
>-compressor is working normally
>-blower fan is working normally
>-air dampers appear to be working normally
>-tube from compressor to condenser is hot
>-tube from condenser into firewall/evaporator is nice and cold
>-tube OUT from firewall/evaporator is warm.. like air temperature warm. ( I
>would assume this would be fairly cool as well, since the evaporator
>probably isn't 100% efficient? )
>-airflow inside the cabin is KIND of cool, but definitely not cold.. hard to
>tell if it's just air temp, but it may feel cooler just because of the rapid
>air flow..
>-hot/cold selector seems to be working fine.. definitely HOT air when
>switched to hot.
>
>I took most of the dash off, to see the cables, dampers etc, and to see if
>there's some kind of physical blockage in there.. nothing obvious.
>
>Before I completely take out the heater/ac housing, do these symptoms tell
>you anything concrete about the evaporator?
>
>Thanks!
>
>Tim
>
>Yikes ==> http://www.diezfamily.us/coppermine/...s.php?album=34

If memory serves me, the Orifice Tube on this CCOT system is located
in the hose that exits the Condenser (locating in this position
reduces refrigerant flow noise in the cabin). Your description
indicates low charge. It might be a leak or it might just be normal
system leakages over the 8 years of service this vehicle has seen.
After recovering the remaining refrigerant I would replace the o-rings
at all of the evaporator connections and replace the Accumulator (the
dessicant is probably saturated after 8 years of life). Recharge the
system and add 50% of the compressor oil (some will be lost with the
Accumulator change) and you should be good to go. (assuming that
you've made a good visual inspection of the other parts of the system
to eliminate obvious problems).
reboot
>

 

On Mon, 12 Jun 2006 16:19:23 -0500, "Diezmon"
<notmyrealemail@fakeemail.com> wrote:

>Hey all,
>
>I've been reading the MANY posts and sites about TJ's and air conditioning
>problems, but didn't find a definite answer to my symptoms. I hope to hell
>it's not the evaporator.
>
>So, here's the deal:
>
>-compressor is working normally
>-blower fan is working normally
>-air dampers appear to be working normally
>-tube from compressor to condenser is hot
>-tube from condenser into firewall/evaporator is nice and cold
>-tube OUT from firewall/evaporator is warm.. like air temperature warm. ( I
>would assume this would be fairly cool as well, since the evaporator
>probably isn't 100% efficient? )
>-airflow inside the cabin is KIND of cool, but definitely not cold.. hard to
>tell if it's just air temp, but it may feel cooler just because of the rapid
>air flow..
>-hot/cold selector seems to be working fine.. definitely HOT air when
>switched to hot.
>
>I took most of the dash off, to see the cables, dampers etc, and to see if
>there's some kind of physical blockage in there.. nothing obvious.
>
>Before I completely take out the heater/ac housing, do these symptoms tell
>you anything concrete about the evaporator?
>
>Thanks!
>
>Tim
>
>Yikes ==> http://www.diezfamily.us/coppermine/...s.php?album=34

If memory serves me, the Orifice Tube on this CCOT system is located
in the hose that exits the Condenser (locating in this position
reduces refrigerant flow noise in the cabin). Your description
indicates low charge. It might be a leak or it might just be normal
system leakages over the 8 years of service this vehicle has seen.
After recovering the remaining refrigerant I would replace the o-rings
at all of the evaporator connections and replace the Accumulator (the
dessicant is probably saturated after 8 years of life). Recharge the
system and add 50% of the compressor oil (some will be lost with the
Accumulator change) and you should be good to go. (assuming that
you've made a good visual inspection of the other parts of the system
to eliminate obvious problems).
reboot
>

 

On Mon, 12 Jun 2006 16:19:23 -0500, "Diezmon"
<notmyrealemail@fakeemail.com> wrote:

>Hey all,
>
>I've been reading the MANY posts and sites about TJ's and air conditioning
>problems, but didn't find a definite answer to my symptoms. I hope to hell
>it's not the evaporator.
>
>So, here's the deal:
>
>-compressor is working normally
>-blower fan is working normally
>-air dampers appear to be working normally
>-tube from compressor to condenser is hot
>-tube from condenser into firewall/evaporator is nice and cold
>-tube OUT from firewall/evaporator is warm.. like air temperature warm. ( I
>would assume this would be fairly cool as well, since the evaporator
>probably isn't 100% efficient? )
>-airflow inside the cabin is KIND of cool, but definitely not cold.. hard to
>tell if it's just air temp, but it may feel cooler just because of the rapid
>air flow..
>-hot/cold selector seems to be working fine.. definitely HOT air when
>switched to hot.
>
>I took most of the dash off, to see the cables, dampers etc, and to see if
>there's some kind of physical blockage in there.. nothing obvious.
>
>Before I completely take out the heater/ac housing, do these symptoms tell
>you anything concrete about the evaporator?
>
>Thanks!
>
>Tim
>
>Yikes ==> http://www.diezfamily.us/coppermine/...s.php?album=34

If memory serves me, the Orifice Tube on this CCOT system is located
in the hose that exits the Condenser (locating in this position
reduces refrigerant flow noise in the cabin). Your description
indicates low charge. It might be a leak or it might just be normal
system leakages over the 8 years of service this vehicle has seen.
After recovering the remaining refrigerant I would replace the o-rings
at all of the evaporator connections and replace the Accumulator (the
dessicant is probably saturated after 8 years of life). Recharge the
system and add 50% of the compressor oil (some will be lost with the
Accumulator change) and you should be good to go. (assuming that
you've made a good visual inspection of the other parts of the system
to eliminate obvious problems).
reboot
>

 

Not possible to diagnose this problem conclusively without pressure
readings.
What is the outside air temperature?
98 TJ, I assume using r134a
if the ambient air temp is around 90+ then your high side readings will be
in the 275 - 310 psi range
R134 runs at higher pressure than r12.
Your low side readings should be in the 25-35 psi range.
Stick a thermometer in the center register and get a reading - engine
running
around 1200 rpm, air on recirc, fan on high.

If the ac is low, then the compressor should be cycling on-off due to the
low pressure cutout
switch opens the clutch circuit around 20 - 25 psi. The goal is to keep
the evaporator core temperature around 35 -45 degrees. Any colder will cause
icing.

fyi - an evaporator icing up can cause similar condition to what you are
describing.

frosty

"reboot" <reboot@nothere.com> wrote in message
news:ig4ja2pbnrd893pa17icrvvgjbr0m20su1@4ax.com...
> On Mon, 12 Jun 2006 16:19:23 -0500, "Diezmon"
> <notmyrealemail@fakeemail.com> wrote:
>
> >Hey all,
> >
> >I've been reading the MANY posts and sites about TJ's and air
conditioning
> >problems, but didn't find a definite answer to my symptoms. I hope to
hell
> >it's not the evaporator.
> >
> >So, here's the deal:
> >
> >-compressor is working normally
> >-blower fan is working normally
> >-air dampers appear to be working normally
> >-tube from compressor to condenser is hot
> >-tube from condenser into firewall/evaporator is nice and cold
> >-tube OUT from firewall/evaporator is warm.. like air temperature warm.
( I
> >would assume this would be fairly cool as well, since the evaporator
> >probably isn't 100% efficient? )
> >-airflow inside the cabin is KIND of cool, but definitely not cold.. hard
to
> >tell if it's just air temp, but it may feel cooler just because of the
rapid
> >air flow..
> >-hot/cold selector seems to be working fine.. definitely HOT air when
> >switched to hot.
> >
> >I took most of the dash off, to see the cables, dampers etc, and to see
if
> >there's some kind of physical blockage in there.. nothing obvious.
> >
> >Before I completely take out the heater/ac housing, do these symptoms
tell
> >you anything concrete about the evaporator?
> >
> >Thanks!
> >
> >Tim
> >
> >Yikes ==> http://www.diezfamily.us/coppermine/...s.php?album=34
>
> If memory serves me, the Orifice Tube on this CCOT system is located
> in the hose that exits the Condenser (locating in this position
> reduces refrigerant flow noise in the cabin). Your description
> indicates low charge. It might be a leak or it might just be normal
> system leakages over the 8 years of service this vehicle has seen.
> After recovering the remaining refrigerant I would replace the o-rings
> at all of the evaporator connections and replace the Accumulator (the
> dessicant is probably saturated after 8 years of life). Recharge the
> system and add 50% of the compressor oil (some will be lost with the
> Accumulator change) and you should be good to go. (assuming that
> you've made a good visual inspection of the other parts of the system
> to eliminate obvious problems).
> reboot
> >

 

Not possible to diagnose this problem conclusively without pressure
readings.
What is the outside air temperature?
98 TJ, I assume using r134a
if the ambient air temp is around 90+ then your high side readings will be
in the 275 - 310 psi range
R134 runs at higher pressure than r12.
Your low side readings should be in the 25-35 psi range.
Stick a thermometer in the center register and get a reading - engine
running
around 1200 rpm, air on recirc, fan on high.

If the ac is low, then the compressor should be cycling on-off due to the
low pressure cutout
switch opens the clutch circuit around 20 - 25 psi. The goal is to keep
the evaporator core temperature around 35 -45 degrees. Any colder will cause
icing.

fyi - an evaporator icing up can cause similar condition to what you are
describing.

frosty

"reboot" <reboot@nothere.com> wrote in message
news:ig4ja2pbnrd893pa17icrvvgjbr0m20su1@4ax.com...
> On Mon, 12 Jun 2006 16:19:23 -0500, "Diezmon"
> <notmyrealemail@fakeemail.com> wrote:
>
> >Hey all,
> >
> >I've been reading the MANY posts and sites about TJ's and air
conditioning
> >problems, but didn't find a definite answer to my symptoms. I hope to
hell
> >it's not the evaporator.
> >
> >So, here's the deal:
> >
> >-compressor is working normally
> >-blower fan is working normally
> >-air dampers appear to be working normally
> >-tube from compressor to condenser is hot
> >-tube from condenser into firewall/evaporator is nice and cold
> >-tube OUT from firewall/evaporator is warm.. like air temperature warm.
( I
> >would assume this would be fairly cool as well, since the evaporator
> >probably isn't 100% efficient? )
> >-airflow inside the cabin is KIND of cool, but definitely not cold.. hard
to
> >tell if it's just air temp, but it may feel cooler just because of the
rapid
> >air flow..
> >-hot/cold selector seems to be working fine.. definitely HOT air when
> >switched to hot.
> >
> >I took most of the dash off, to see the cables, dampers etc, and to see
if
> >there's some kind of physical blockage in there.. nothing obvious.
> >
> >Before I completely take out the heater/ac housing, do these symptoms
tell
> >you anything concrete about the evaporator?
> >
> >Thanks!
> >
> >Tim
> >
> >Yikes ==> http://www.diezfamily.us/coppermine/...s.php?album=34
>
> If memory serves me, the Orifice Tube on this CCOT system is located
> in the hose that exits the Condenser (locating in this position
> reduces refrigerant flow noise in the cabin). Your description
> indicates low charge. It might be a leak or it might just be normal
> system leakages over the 8 years of service this vehicle has seen.
> After recovering the remaining refrigerant I would replace the o-rings
> at all of the evaporator connections and replace the Accumulator (the
> dessicant is probably saturated after 8 years of life). Recharge the
> system and add 50% of the compressor oil (some will be lost with the
> Accumulator change) and you should be good to go. (assuming that
> you've made a good visual inspection of the other parts of the system
> to eliminate obvious problems).
> reboot
> >

 

Not possible to diagnose this problem conclusively without pressure
readings.
What is the outside air temperature?
98 TJ, I assume using r134a
if the ambient air temp is around 90+ then your high side readings will be
in the 275 - 310 psi range
R134 runs at higher pressure than r12.
Your low side readings should be in the 25-35 psi range.
Stick a thermometer in the center register and get a reading - engine
running
around 1200 rpm, air on recirc, fan on high.

If the ac is low, then the compressor should be cycling on-off due to the
low pressure cutout
switch opens the clutch circuit around 20 - 25 psi. The goal is to keep
the evaporator core temperature around 35 -45 degrees. Any colder will cause
icing.

fyi - an evaporator icing up can cause similar condition to what you are
describing.

frosty

"reboot" <reboot@nothere.com> wrote in message
news:ig4ja2pbnrd893pa17icrvvgjbr0m20su1@4ax.com...
> On Mon, 12 Jun 2006 16:19:23 -0500, "Diezmon"
> <notmyrealemail@fakeemail.com> wrote:
>
> >Hey all,
> >
> >I've been reading the MANY posts and sites about TJ's and air
conditioning
> >problems, but didn't find a definite answer to my symptoms. I hope to
hell
> >it's not the evaporator.
> >
> >So, here's the deal:
> >
> >-compressor is working normally
> >-blower fan is working normally
> >-air dampers appear to be working normally
> >-tube from compressor to condenser is hot
> >-tube from condenser into firewall/evaporator is nice and cold
> >-tube OUT from firewall/evaporator is warm.. like air temperature warm.
( I
> >would assume this would be fairly cool as well, since the evaporator
> >probably isn't 100% efficient? )
> >-airflow inside the cabin is KIND of cool, but definitely not cold.. hard
to
> >tell if it's just air temp, but it may feel cooler just because of the
rapid
> >air flow..
> >-hot/cold selector seems to be working fine.. definitely HOT air when
> >switched to hot.
> >
> >I took most of the dash off, to see the cables, dampers etc, and to see
if
> >there's some kind of physical blockage in there.. nothing obvious.
> >
> >Before I completely take out the heater/ac housing, do these symptoms
tell
> >you anything concrete about the evaporator?
> >
> >Thanks!
> >
> >Tim
> >
> >Yikes ==> http://www.diezfamily.us/coppermine/...s.php?album=34
>
> If memory serves me, the Orifice Tube on this CCOT system is located
> in the hose that exits the Condenser (locating in this position
> reduces refrigerant flow noise in the cabin). Your description
> indicates low charge. It might be a leak or it might just be normal
> system leakages over the 8 years of service this vehicle has seen.
> After recovering the remaining refrigerant I would replace the o-rings
> at all of the evaporator connections and replace the Accumulator (the
> dessicant is probably saturated after 8 years of life). Recharge the
> system and add 50% of the compressor oil (some will be lost with the
> Accumulator change) and you should be good to go. (assuming that
> you've made a good visual inspection of the other parts of the system
> to eliminate obvious problems).
> reboot
> >