Honda Car Forum

I have a 1992 honda civic that used the old school R12 refrigerant. My
brother a few years back did a motor swap on the car and of course swapped
out the compressor for the a/c at the same time. The new compressor is off
a brand new car so its r134a compliant. To get the a/c working again he
took the vehicle to a shop that supposedly changed out the seals and
evacuated and rechraged the system with r134a refrigerant.

All was working well up until this spring when my a/c stopped working.

I recharged the system with a set of brand new gauges and genuine virgin
r134a refrigerant. All was working well up until my curiousity uncovered
something quite interesting.

My a/c blows about 10-12 degrees celsius which is acceptable for ambient
temp of about 20 degrees celsius. I decided to hook up a set of gauges to
my car and found the readings to be quite off from what I think they should
roughly be.

The low side suction pressure is about 23-28 psi and the high side is at a
crazy 250-260 psi! The line to the condensor is extremely hot which i
already know is not normal. The car cools reasonably well so I'm lost as to
what could be wrong. According to my honda service manual a excessive high
discharge line pressures and abnormally hot condenser lines indicates a
restricted refrigerant flow in the system.

here are some observed items:

1. the receiver drier is the original R12 receiver drier (the shop was
stupid enough not to change it out to comply with r134a)
2. There is a small refrigerant leak from the acme fitting on the low side.
3. The discharge line into the condenser is insanely hot
4. The suction line is noticably cold
5. the receiver drier feels very warm to the touch and the line going to
the evaporator is also very warm to the touch.
6. The ambient temperature isn't hot enough to make the suction line to
sweat.
7. The high side pressure before starting the car is only at 90 psi. As
compressor run time increases the higher the pressure and the higher the
condenser line temps.
8. When the compressor cycles on and off the high side pressure can
fluctuate as much as 25-30 psi. When the compressor pumps the pressure
shoots up very fast and when it stops it drops fairly rapidly down about
20-30 psi before really coming to a stop. After the cycle starts over again
with discharge pressures getting higher and higher.
9. I highly doub the system is overcharged b/c the low side pressures are
so low.
10. The compressor i am using is brand new straight from honda.


With ambient temps on the cooler than average side and a discharge pressure
so high I can only imagine what the end result would be when the ambient
temp shoots to over 30 degrees. My a/c would literally explode!

I can't see how the system is restricted other than two places. The
expansion valve or the receiver drier.

The expansion valve couldn't be stuck closed b/c I get a decent amount of
cooling
The expansion valve couldn't be stuck open b/c the evaporator doesn't freeze
over
The receiver drier is the original r12 drier so that should be an obvious
sign of bad a/c retrofitting. I will change that out

I was good at fixing R12 a/c systems in older cars but this retrofitted
civic is a tough one to figure out. I don't want to take it to honda and
spend 500 bucks to fix it when I have all the equipment to do it.

Can someone tell me what the heck is wrong?

Thanks

You can find the pressure charts for that car with for R134a at
http://www.honda.co.uk/owner/civicmanual/pdf/22-20.pdf.

R134a (1,1,1,2-tetrafluoroethane) is a larger molecule than R12
(dichlorodifluoromethane) so I would imagine that the expansion valve
should be larger to accommodate that. Was it replaced when you had the
seals etc. replaced?

Steve wrote:
>
> I have a 1992 honda civic that used the old school R12 refrigerant. My
> brother a few years back did a motor swap on the car and of course swapped
> out the compressor for the a/c at the same time. The new compressor is off
> a brand new car so its r134a compliant. To get the a/c working again he
> took the vehicle to a shop that supposedly changed out the seals and
> evacuated and rechraged the system with r134a refrigerant.
>
> All was working well up until this spring when my a/c stopped working.
>
> I recharged the system with a set of brand new gauges and genuine virgin
> r134a refrigerant. All was working well up until my curiousity uncovered
> something quite interesting.
>
> My a/c blows about 10-12 degrees celsius which is acceptable for ambient
> temp of about 20 degrees celsius. I decided to hook up a set of gauges to
> my car and found the readings to be quite off from what I think they should
> roughly be.
>
> The low side suction pressure is about 23-28 psi and the high side is at a
> crazy 250-260 psi! The line to the condensor is extremely hot which i
> already know is not normal. The car cools reasonably well so I'm lost as to
> what could be wrong. According to my honda service manual a excessive high
> discharge line pressures and abnormally hot condenser lines indicates a
> restricted refrigerant flow in the system.
>
> here are some observed items:
>
> 1. the receiver drier is the original R12 receiver drier (the shop was
> stupid enough not to change it out to comply with r134a)
> 2. There is a small refrigerant leak from the acme fitting on the low side.
> 3. The discharge line into the condenser is insanely hot
> 4. The suction line is noticably cold
> 5. the receiver drier feels very warm to the touch and the line going to
> the evaporator is also very warm to the touch.
> 6. The ambient temperature isn't hot enough to make the suction line to
> sweat.
> 7. The high side pressure before starting the car is only at 90 psi. As
> compressor run time increases the higher the pressure and the higher the
> condenser line temps.
> 8. When the compressor cycles on and off the high side pressure can
> fluctuate as much as 25-30 psi. When the compressor pumps the pressure
> shoots up very fast and when it stops it drops fairly rapidly down about
> 20-30 psi before really coming to a stop. After the cycle starts over again
> with discharge pressures getting higher and higher.
> 9. I highly doub the system is overcharged b/c the low side pressures are
> so low.
> 10. The compressor i am using is brand new straight from honda.
>
> With ambient temps on the cooler than average side and a discharge pressure
> so high I can only imagine what the end result would be when the ambient
> temp shoots to over 30 degrees. My a/c would literally explode!
>
> I can't see how the system is restricted other than two places. The
> expansion valve or the receiver drier.
>
> The expansion valve couldn't be stuck closed b/c I get a decent amount of
> cooling
> The expansion valve couldn't be stuck open b/c the evaporator doesn't freeze
> over
> The receiver drier is the original r12 drier so that should be an obvious
> sign of bad a/c retrofitting. I will change that out
>
> I was good at fixing R12 a/c systems in older cars but this retrofitted
> civic is a tough one to figure out. I don't want to take it to honda and
> spend 500 bucks to fix it when I have all the equipment to do it.
>
> Can someone tell me what the heck is wrong?
>
> Thanks

On Fri, 28 May 2004 05:13:13 GMT, "Steve" <idontthinkso@pissoff.com> wrote:

>I have a 1992 honda civic that used the old school R12 refrigerant. My
>brother a few years back did a motor swap on the car and of course swapped
>out the compressor for the a/c at the same time. The new compressor is off
>a brand new car so its r134a compliant. To get the a/c working again he
>took the vehicle to a shop that supposedly changed out the seals and
>evacuated and rechraged the system with r134a refrigerant.
>
>All was working well up until this spring when my a/c stopped working.
>
>I recharged the system with a set of brand new gauges and genuine virgin
>r134a refrigerant. All was working well up until my curiousity uncovered
>something quite interesting.
>
>My a/c blows about 10-12 degrees celsius which is acceptable for ambient
>temp of about 20 degrees celsius. I decided to hook up a set of gauges to
>my car and found the readings to be quite off from what I think they should
>roughly be.
>
>The low side suction pressure is about 23-28 psi and the high side is at a
>crazy 250-260 psi! The line to the condensor is extremely hot which i
>already know is not normal. The car cools reasonably well so I'm lost as to
>what could be wrong. According to my honda service manual a excessive high
>discharge line pressures and abnormally hot condenser lines indicates a
>restricted refrigerant flow in the system.
>
>here are some observed items:
>
>1. the receiver drier is the original R12 receiver drier (the shop was
>stupid enough not to change it out to comply with r134a)
>2. There is a small refrigerant leak from the acme fitting on the low side.
>3. The discharge line into the condenser is insanely hot
>4. The suction line is noticably cold
>5. the receiver drier feels very warm to the touch and the line going to
>the evaporator is also very warm to the touch.
>6. The ambient temperature isn't hot enough to make the suction line to
>sweat.
>7. The high side pressure before starting the car is only at 90 psi. As
>compressor run time increases the higher the pressure and the higher the
>condenser line temps.
>8. When the compressor cycles on and off the high side pressure can
>fluctuate as much as 25-30 psi. When the compressor pumps the pressure
>shoots up very fast and when it stops it drops fairly rapidly down about
>20-30 psi before really coming to a stop. After the cycle starts over again
>with discharge pressures getting higher and higher.
>9. I highly doub the system is overcharged b/c the low side pressures are
>so low.
>10. The compressor i am using is brand new straight from honda.
>
>
>With ambient temps on the cooler than average side and a discharge pressure
>so high I can only imagine what the end result would be when the ambient
>temp shoots to over 30 degrees. My a/c would literally explode!
>
>I can't see how the system is restricted other than two places. The
>expansion valve or the receiver drier.
>
>The expansion valve couldn't be stuck closed b/c I get a decent amount of
>cooling
>The expansion valve couldn't be stuck open b/c the evaporator doesn't freeze
>over
>The receiver drier is the original r12 drier so that should be an obvious
>sign of bad a/c retrofitting. I will change that out
>
>I was good at fixing R12 a/c systems in older cars but this retrofitted
>civic is a tough one to figure out. I don't want to take it to honda and
>spend 500 bucks to fix it when I have all the equipment to do it.
>
>Can someone tell me what the heck is wrong?

I think you're probably on the right track with the receiver/dryer but
while the system is open take a look at the oil which is lurking around at
the fittings and in the receiver. Did the shop which did the conversion
flush out the old R-12 petroleum-based lube? Which synthetic oil did they
replace it with - I'd assume there'd be some lube left in the "new"
compressor, likely PAG - but what did they add to bring the lubricant up to
the correct level?

Take a look at the Forum at www.aircondition.com and search the msgs there
for "black death". PAG oil is particularly hygroscopic and a mixture of
moisture and old petroleum-based lubricant has led to the formation of a
thick black sludge which plugs the A/C lines. If your low side gets to a
low enough pressure and there is even a minor leak which allows moisture to
get sucked into the system, bad things can happen even with PAG only; add
in some old R-12 lubricant and you get the "black death". I hope yours
hasn't gotten that bad yet but putting in fresh PAG without changing out
the old receiver/dryer, which probably had some moisture in it, was a major
blunder IMO.

Rgds, George Macdonald

"Just because they're paranoid doesn't mean you're not psychotic" - Who, me??

I am not sure how to use the charging chart that was sent to me via that
link from George. I am thinking of pulling the entire system and blowing
out the lines and such with compressed air.

How do I know if there is too much oil or moisture in the system.

Strangely the outlet temp from the evap is only about 12C. My toyota which
came from factory with r134a cools down the 7C in the same exact conditions.

So what are the obvious signs of a stuck/closed expansion valve?

Does honda use expansion valve?

What temp are the lines supposed to be at?

How do I know if the receiver drier is starting to plug up?

Thanks

"George Macdonald" <fammacd=!SPAM^nothanks@tellurian.com> wrote in message
news:3mvdb0t1mj7ait0n830stv176nfvgkupst@4ax.com...
> On Fri, 28 May 2004 05:13:13 GMT, "Steve" <idontthinkso@pissoff.com>
wrote:
>
> >I have a 1992 honda civic that used the old school R12 refrigerant. My
> >brother a few years back did a motor swap on the car and of course
swapped
> >out the compressor for the a/c at the same time. The new compressor is
off
> >a brand new car so its r134a compliant. To get the a/c working again he
> >took the vehicle to a shop that supposedly changed out the seals and
> >evacuated and rechraged the system with r134a refrigerant.
> >
> >All was working well up until this spring when my a/c stopped working.
> >
> >I recharged the system with a set of brand new gauges and genuine virgin
> >r134a refrigerant. All was working well up until my curiousity uncovered
> >something quite interesting.
> >
> >My a/c blows about 10-12 degrees celsius which is acceptable for ambient
> >temp of about 20 degrees celsius. I decided to hook up a set of gauges
to
> >my car and found the readings to be quite off from what I think they
should
> >roughly be.
> >
> >The low side suction pressure is about 23-28 psi and the high side is at
a
> >crazy 250-260 psi! The line to the condensor is extremely hot which i
> >already know is not normal. The car cools reasonably well so I'm lost as
to
> >what could be wrong. According to my honda service manual a excessive
high
> >discharge line pressures and abnormally hot condenser lines indicates a
> >restricted refrigerant flow in the system.
> >
> >here are some observed items:
> >
> >1. the receiver drier is the original R12 receiver drier (the shop was
> >stupid enough not to change it out to comply with r134a)
> >2. There is a small refrigerant leak from the acme fitting on the low
side.
> >3. The discharge line into the condenser is insanely hot
> >4. The suction line is noticably cold
> >5. the receiver drier feels very warm to the touch and the line going to
> >the evaporator is also very warm to the touch.
> >6. The ambient temperature isn't hot enough to make the suction line to
> >sweat.
> >7. The high side pressure before starting the car is only at 90 psi. As
> >compressor run time increases the higher the pressure and the higher the
> >condenser line temps.
> >8. When the compressor cycles on and off the high side pressure can
> >fluctuate as much as 25-30 psi. When the compressor pumps the pressure
> >shoots up very fast and when it stops it drops fairly rapidly down about
> >20-30 psi before really coming to a stop. After the cycle starts over
again
> >with discharge pressures getting higher and higher.
> >9. I highly doub the system is overcharged b/c the low side pressures
are
> >so low.
> >10. The compressor i am using is brand new straight from honda.
> >
> >
> >With ambient temps on the cooler than average side and a discharge
pressure
> >so high I can only imagine what the end result would be when the ambient
> >temp shoots to over 30 degrees. My a/c would literally explode!
> >
> >I can't see how the system is restricted other than two places. The
> >expansion valve or the receiver drier.
> >
> >The expansion valve couldn't be stuck closed b/c I get a decent amount of
> >cooling
> >The expansion valve couldn't be stuck open b/c the evaporator doesn't
freeze
> >over
> >The receiver drier is the original r12 drier so that should be an obvious
> >sign of bad a/c retrofitting. I will change that out
> >
> >I was good at fixing R12 a/c systems in older cars but this retrofitted
> >civic is a tough one to figure out. I don't want to take it to honda and
> >spend 500 bucks to fix it when I have all the equipment to do it.
> >
> >Can someone tell me what the heck is wrong?
>
> I think you're probably on the right track with the receiver/dryer but
> while the system is open take a look at the oil which is lurking around at
> the fittings and in the receiver. Did the shop which did the conversion
> flush out the old R-12 petroleum-based lube? Which synthetic oil did they
> replace it with - I'd assume there'd be some lube left in the "new"
> compressor, likely PAG - but what did they add to bring the lubricant up
to
> the correct level?
>
> Take a look at the Forum at www.aircondition.com and search the msgs there
> for "black death". PAG oil is particularly hygroscopic and a mixture of
> moisture and old petroleum-based lubricant has led to the formation of a
> thick black sludge which plugs the A/C lines. If your low side gets to a
> low enough pressure and there is even a minor leak which allows moisture
to
> get sucked into the system, bad things can happen even with PAG only; add
> in some old R-12 lubricant and you get the "black death". I hope yours
> hasn't gotten that bad yet but putting in fresh PAG without changing out
> the old receiver/dryer, which probably had some moisture in it, was a
major
> blunder IMO.
>
> Rgds, George Macdonald
>
> "Just because they're paranoid doesn't mean you're not psychotic" - Who,
me??

On Fri, 28 May 2004, Randolph wrote:

> R134a (1,1,1,2-tetrafluoroethane) is a larger molecule than R12
> (dichlorodifluoromethane) so I would imagine that the expansion valve
> should be larger to accommodate that.

That seems commonsensical, but it's frequently not the case. I can think
of several car lines that use the same expansion valve for 12 or 134a.

I think the OP probably has noncondensibles in his system, and I wonder if
his system is properly charged with the correct amount and type of oil.

Steve wrote:

> My a/c blows about 10-12 degrees celsius which is acceptable for ambient
> temp of about 20 degrees celsius. I decided to hook up a set of gauges to
> my car and found the readings to be quite off from what I think they should
> roughly be.
>
> The low side suction pressure is about 23-28 psi and the high side is at a
> crazy 250-260 psi! The line to the condensor is extremely hot which i
> already know is not normal. The car cools reasonably well so I'm lost as to
> what could be wrong.

8C drop is cooling "reasonably well?" I disagree.

> 1. the receiver drier is the original R12 receiver drier (the shop was
> stupid enough not to change it out to comply with r134a)

You have GOT to be kidding.

My guess is the dessicant bag in the drier probably ruptured, and all
the dessicant powder headed downstream and plugged the orifice tube (or
TXV) solid. That would explain the high pressure (the system is mostly
obstructed) and the lack of cooling (a drop of only 8-10C is horrible).

If that's the case, the only solution is opeing up the system, flushing
all the lines, condensor, and evaporator, and replacing the drier and
expansion orifice or TXV (I have no idea if Honda uses a TXV or an
orifice tube, but they perform the same job).

I just order a bottle of pag oil and a new factory approved r134a receiver
drier.

will simply re-replacing the compressor oil and drier remove any possible
trace amounts of mineral oil?

I'm sure there is already pag in the system but you never know what idiots
are working on a/c systems with no real experience.

I am hoping that the blockage is in the receiver drier and not the txv. I'm
almost certain the txv isn't clogged b/c it blows cold.

how can I effective flush a condenser myself cheaply?

Can anyone tell me why my head pressure is still so high ?

Thanks a million, your suggestions and comments are greatly appreciated.

Thanks

On Fri, 28 May 2004 15:21:06 GMT, "Steve" <noway@nospam.com> wrote:

>I am not sure how to use the charging chart that was sent to me via that
>link from George. I am thinking of pulling the entire system and blowing
>out the lines and such with compressed air.

If you're going that far, the recommended method is to flush with solvent
(naphtha ?) first, dry with compressed air and then of course, pull a deep
vacuum for 2hrs or so.

>How do I know if there is too much oil or moisture in the system.
>
>Strangely the outlet temp from the evap is only about 12C. My toyota which
>came from factory with r134a cools down the 7C in the same exact conditions.
>
>So what are the obvious signs of a stuck/closed expansion valve?
>
>Does honda use expansion valve?

Yes Honda used and continues to use AFAIK, an expansion valve.

>What temp are the lines supposed to be at?
>
>How do I know if the receiver drier is starting to plug up?

Rgds, George Macdonald

"Just because they're paranoid doesn't mean you're not psychotic" - Who, me??

> > R134a (1,1,1,2-tetrafluoroethane) is a larger molecule than R12
> > (dichlorodifluoromethane) so I would imagine that the expansion valve
> > should be larger to accommodate that.

R-134A is actually a SMALLER molecule. That's why barrier hoses are needed.
If you don't believe it, do a Google search using "R134A" and "smaller
molecule".

i didn't try the water/pressure drop test. The fan is running on high and
there is very warm air coming out from the condenser. The lines even going
up to the evaporator are warmer than any r134a car that I've touched.

I was thinking of flushing the condenser out and draining all the oil from
the condenser. I also intend to change the receiver drier and dump all the
crap oil in the compressor and replace it with new oil.

I am not sure at this point whether or not I should use ester oil or pag.
The compressor came from factory with pag but my other parts of my a/c used
r12 so techincally ester would be better for it.

What do I do when a compressor calls for pag but my other parts are r12
equipped?

"Honda Doc" <tophondadoc@hotmail.nospam.com> wrote in message
news:mp-dnbX7B6gfaSrdRVn-tw@comcast.com...
> Sounds more like a condenser problem. Possibly blocked or not enough air
> passing across it. Is the cooling fan at the condenser coming on? Try
> spraying cold water on it with it running and see if the pressure drops.
>
>
>
> "Steve" <idontthinkso@pissoff.com> wrote in message
> news:JTztc.609356$Ig.32213@pd7tw2no...
> > I have a 1992 honda civic that used the old school R12 refrigerant. My
> > brother a few years back did a motor swap on the car and of course
swapped
> > out the compressor for the a/c at the same time. The new compressor is
> off
> > a brand new car so its r134a compliant. To get the a/c working again he
> > took the vehicle to a shop that supposedly changed out the seals and
> > evacuated and rechraged the system with r134a refrigerant.
> >
> > All was working well up until this spring when my a/c stopped working.
> >
> > I recharged the system with a set of brand new gauges and genuine virgin
> > r134a refrigerant. All was working well up until my curiousity
uncovered
> > something quite interesting.
> >
> > My a/c blows about 10-12 degrees celsius which is acceptable for ambient
> > temp of about 20 degrees celsius. I decided to hook up a set of gauges
to
> > my car and found the readings to be quite off from what I think they
> should
> > roughly be.
> >
> > The low side suction pressure is about 23-28 psi and the high side is at
a
> > crazy 250-260 psi! The line to the condensor is extremely hot which i
> > already know is not normal. The car cools reasonably well so I'm lost
as
> to
> > what could be wrong. According to my honda service manual a excessive
> high
> > discharge line pressures and abnormally hot condenser lines indicates a
> > restricted refrigerant flow in the system.
> >
> > here are some observed items:
> >
> > 1. the receiver drier is the original R12 receiver drier (the shop was
> > stupid enough not to change it out to comply with r134a)
> > 2. There is a small refrigerant leak from the acme fitting on the low
> side.
> > 3. The discharge line into the condenser is insanely hot
> > 4. The suction line is noticably cold
> > 5. the receiver drier feels very warm to the touch and the line going
to
> > the evaporator is also very warm to the touch.
> > 6. The ambient temperature isn't hot enough to make the suction line to
> > sweat.
> > 7. The high side pressure before starting the car is only at 90 psi.
As
> > compressor run time increases the higher the pressure and the higher the
> > condenser line temps.
> > 8. When the compressor cycles on and off the high side pressure can
> > fluctuate as much as 25-30 psi. When the compressor pumps the pressure
> > shoots up very fast and when it stops it drops fairly rapidly down about
> > 20-30 psi before really coming to a stop. After the cycle starts over
> again
> > with discharge pressures getting higher and higher.
> > 9. I highly doub the system is overcharged b/c the low side pressures
are
> > so low.
> > 10. The compressor i am using is brand new straight from honda.
> >
> >
> > With ambient temps on the cooler than average side and a discharge
> pressure
> > so high I can only imagine what the end result would be when the ambient
> > temp shoots to over 30 degrees. My a/c would literally explode!
> >
> > I can't see how the system is restricted other than two places. The
> > expansion valve or the receiver drier.
> >
> > The expansion valve couldn't be stuck closed b/c I get a decent amount
of
> > cooling
> > The expansion valve couldn't be stuck open b/c the evaporator doesn't
> freeze
> > over
> > The receiver drier is the original r12 drier so that should be an
obvious
> > sign of bad a/c retrofitting. I will change that out
> >
> > I was good at fixing R12 a/c systems in older cars but this retrofitted
> > civic is a tough one to figure out. I don't want to take it to honda
and
> > spend 500 bucks to fix it when I have all the equipment to do it.
> >
> > Can someone tell me what the heck is wrong?
> >
> > Thanks
> >
> >
> >
> >
>
>