Air Conditioning

[Don Bradner]

There've been a few A/C discussions in various threads recently - must be a
calendar thing. I thought I would add my own.

I've always been very impressed with how well the overhead chassis air cooled
driver and passenger in Blue Thunder. In previous SOBs on really hot days the
dash air was never enough - had to run the generator and a house A/C as well.
Blue Thunder is one of the 90s with the condenser back at the radiator rather
than on top of the front cap.

10 days or so ago there was a big heatwave on the west coast, and I turned on
the A/C for the first time in a couple of months - no cold at all, sigh. Ran the
generator as needed to keep things decent, and waited until we got home to check
things out.

On top of the hoses as they leave the compressor are R12-to-R134a elbow service
ports. Both were loose, and a small amount of pressure on the high-side fitting
caused it to separate. There was no gas escape, indicating that it was all
long-since leaked out.

I assume that I am the culprit on this. I had to drop the pump in order to
disconnect one of the gate valves when I was searching for my chassis heater
problems, and I'm guessing I hit the fittings at some point during the process.
They are rather exposed and easy to collide with.

A local outfit did the service, replacing both fittings and using 7-1/4 lbs of
R134a. An expensive lesson, for sure, over $600 bottom line.

The records from the coach's second owner shows a $700 bill in July of 2001 for
"A/C repair" so I'm guessing that may have been the original conversion.

I know there are a number of folks who have posted that their dash air does not
work, and they just use the generator/house air solution. We considered that,
but even with the high cost of repair the economics appear to be in favor of the
repair route. Our generator pulls about 1/2 gallon per hour when doing light
work like a single air conditioner. At $5 per gallon that would mean $600 would
run the A/C for 240 hours. At most that would be a couple of years for us, and
probably less. We will be traveling to the East Coast in August, and are likely
to be in hot weather until we leave Florida in November.

I'll be sorry if it turns out that I have a leak somewhere else, but I'm fairly
confident that I don't. The tech put plenty of fluorescent dye in with the
refrigerant, and nothing has shown up anywhere.


Don Bradner
90 PT40 "Blue Thunder"
Eureka, CA

[Terry Neal]

Thanks Don for this info. Good things to consider. My dash air has
always been just average performance so I suspect the dryer needs
replacement as well as charging the refrigerant. As I recall, it is
still R12. I do have the eqpt to change it over to R134A though. The
condenser sits on top of the roof and I'll head up there to make sure
that it's clean & getting proper air flow.



Appreciate your sharing your experience on this subject. We'll be
seeing 100+ soon in Montana & I want to be ready for it.

Terry

Terry Neal

Bozeman, MT

82PT40 6V92TA

74FC34 6V53T











Don Bradner wrote:







There've been a few A/C discussions in various threads recently -

must be a calendar thing. I thought I would add my own.







I've always been very impressed with how well the overhead chassis air

cooled driver and passenger in Blue Thunder. In previous SOBs on really

hot days the dash air was never enough - had to run the generator and a

house A/C as well. Blue Thunder is one of the 90s with the condenser

back at the radiator rather than on top of the front cap.







10 days or so ago there was a big heatwave on the west coast, and I

turned on the A/C for the first time in a couple of months - no cold at

all, sigh. Ran the generator as needed to keep things decent, and

waited until we got home to check things out.







On top of the hoses as they leave the compressor are R12-to-R134a elbow

service ports. Both were loose, and a small amount of pressure on the

high-side fitting caused it to separate. There was no gas escape,

indicating that it was all long-since leaked out.







I assume that I am the culprit on this. I had to drop the pump in order

to disconnect one of the gate valves when I was searching for my

chassis heater problems, and I'm guessing I hit the fittings at some

point during the process. They are rather exposed and easy to collide

with.







A local outfit did the service, replacing both fittings and using 7-1/4

lbs of R134a. An expensive lesson, for sure, over $600 bottom line.







The records from the coach's second owner shows a $700 bill in July of

2001 for "A/C repair" so I'm guessing that may have been the original

conversion.







I know there are a number of folks who have posted that their dash air

does not work, and they just use the generator/house air solution. We

considered that, but even with the high cost of repair the economics

appear to be in favor of the repair route. Our generator pulls about

1/2 gallon per hour when doing light work like a single air

conditioner. At $5 per gallon that would mean $600 would run the A/C

for 240 hours. At most that would be a couple of years for us, and

probably less. We will be traveling to the East Coast in August, and

are likely to be in hot weather until we leave Florida in November.







I'll be sorry if it turns out that I have a leak somewhere else, but

I'm fairly confident that I don't. The tech put plenty of fluorescent

dye in with the refrigerant, and nothing has shown up anywhere.







Don Bradner



90 PT40 "Blue Thunder"



Eureka, CA









 
				

[Leroy Eckert]

Mine is the same configuration as yours Don. I do have a small leak somewhere that I cannot find. It leaks down about once per year but works great when it is charged. The leak must be very small. Converted to 134a.
Just curious, where is the expansion valve and evaporator in your coach?

Leroy Eckert
1990 WB-40 Smoke N Mirrors
Dahlonega.GA
Royale Conversion

Don Bradner wrote:

There've been a few A/C discussions in various threads recently - must be a calendar thing. I thought I would add my own.


I've always been very impressed with how well the overhead chassis air cooled driver and passenger in Blue Thunder. In previous SOBs on really hot days the dash air was never enough - had to run the generator and a house A/C as well. Blue Thunder is one of the 90s with the condenser back at the radiator rather than on top of the front cap.

10 days or so ago there was a big heatwave on the west coast, and I turned on the A/C for the first time in a couple of months - no cold at all, sigh. Ran the generator as needed to keep things decent, and waited until we got home to check things out.

On top of the hoses as they leave the compressor are R12-to-R134a elbow service ports. Both were loose, and a small amount of pressure on the high-side fitting caused it to separate. There was no gas escape, indicating that it was all long-since leaked out.

I assume that I am the culprit on this. I had to drop the pump in order to disconnect one of the gate valves
when I was searching for my chassis heater problems, and I'm guessing I hit the fittings at some point during the process. They are rather exposed and easy to collide with.

A local outfit did the service, replacing both fittings and using 7-1/4 lbs of R134a. An expensive lesson, for sure, over $600 bottom line.

The records from the coach's second owner shows a $700 bill in July of 2001 for "A/C repair" so I'm guessing that may have been the original conversion.

I know there are a number of folks who have posted that their dash air does not work, and they just use the generator/house air solution. We considered that, but even with the high cost of repair the economics appear to be in favor of the repair route. Our generator pulls about 1/2 gallon per hour when doing light work like a single air conditioner. At $5 per gallon that would mean $600 would run the A/C for 240 hours. At most that would be a couple of years for us, and probably less. We
will be traveling to the East Coast in August, and are likely to be in hot weather until we leave Florida in November.

I'll be sorry if it turns out that I have a leak somewhere else, but I'm fairly confident that I don't. The tech put plenty of fluorescent dye in with the refrigerant, and nothing has shown up anywhere.

Don Bradner
90 PT40 "Blue Thunder"
Eureka, CA

[Don Bradner]

Presumably over the driver's head, but I've not dug back in there to find out
for sure. While they moved the condensor on ours I don't know why they would
move the evaporator.

On 5/31/2008 at 2:03 PM Leroy Eckert wrote:

>Mine is the same configuration as yours Don. I do have a small leak
>somewhere that I cannot find. It leaks down about once per year but works
>great when it is charged. The leak must be very small. Converted to 134a.
>Just curious, where is the expansion valve and evaporator in your coach?
>
>Leroy Eckert
>1990 WB-40 Smoke N Mirrors
>Dahlonega.GA
>Royale Conversion
>
>Don Bradner wrote:
>There've been a few A/C discussions in various threads recently - must be
>a calendar thing. I thought I would add my own.
>
> I've always been very impressed with how well the overhead chassis air
>cooled driver and passenger in Blue Thunder. In previous SOBs on really
>hot days the dash air was never enough - had to run the generator and a
>house A/C as well. Blue Thunder is one of the 90s with the condenser back
>at the radiator rather than on top of the front cap.
>
> 10 days or so ago there was a big heatwave on the west coast, and I
>turned on the A/C for the first time in a couple of months - no cold at
>all, sigh. Ran the generator as needed to keep things decent, and waited
>until we got home to check things out.
>
> On top of the hoses as they leave the compressor are R12-to-R134a elbow
>service ports. Both were loose, and a small amount of pressure on the
>high-side fitting caused it to separate. There was no gas escape,
>indicating that it was all long-since leaked out.
>
> I assume that I am the culprit on this. I had to drop the pump in order
>to disconnect one of the gate valves when I was searching for my chassis
>heater problems, and I'm guessing I hit the fittings at some point during
>the process. They are rather exposed and easy to collide with.
>
> A local outfit did the service, replacing both fittings and using 7-1/4
>lbs of R134a. An expensive lesson, for sure, over $600 bottom line.
>
> The records from the coach's second owner shows a $700 bill in July of
>2001 for "A/C repair" so I'm guessing that may have been the original
>conversion.
>
> I know there are a number of folks who have posted that their dash air
>does not work, and they just use the generator/house air solution. We
>considered that, but even with the high cost of repair the economics
>appear to be in favor of the repair route. Our generator pulls about 1/2
>gallon per hour when doing light work like a single air conditioner. At $5
>per gallon that would mean $600 would run the A/C for 240 hours. At most
>that would be a couple of years for us, and probably less. We will be
>traveling to the East Coast in August, and are likely to be in hot weather
>until we leave Florida in November.
>
> I'll be sorry if it turns out that I have a leak somewhere else, but I'm
>fairly confident that I don't. The tech put plenty of fluorescent dye in
>with the refrigerant, and nothing has shown up anywhere.
>
> Don Bradner
> 90 PT40 "Blue Thunder"
> Eureka, CA

[Pete Masterson]

When I got my coach, the PO had converted the chassis AC to R134a but
it wasn't working. When I had my radiator work done, I also had the
AC serviced. Took $$$ of R134a. Worked ok, but not great. About a
year later, it wasn't working quite so well. (No leaks were found at
the time the system was recharged -- but, I wonder, are there
inaccessible hoses where a leak could be hiding? In any event, I'm
now at CCW in Riverside having several things attended to -- and I'm
thinking about recharging the AC again ... but I'm not sure I want to
spend another $600 or so on R134a...

I did add a $12 oscillating fan that plugs into the cigarette
lighter. It actually does a great job in keeping me cool until the
coach warms up enough to turn on the genny and the roof-top units.
Often, my heat discomfort is mostly from the radiant heat affect of
the sun beating into the "fishbowl" up front more than the ambient
temperature in the coach being too warm...

Pete Masterson
'95 Blue Bird Wanderlodge WBDA 42
aeonix1@...
On the road at CCW in Riverside, CA



On May 31, 2008, at 11:36 AM, Don Bradner wrote:

> There've been a few A/C discussions in various threads recently -
> must be a calendar thing. I thought I would add my own.
> <snip>
> I know there are a number of folks who have posted that their dash
> air does not work, and they just use the generator/house air
> solution. We considered that, but even with the high cost of repair
> the economics appear to be in favor of the repair route. Our
> generator pulls about 1/2 gallon per hour when doing light work
> like a single air conditioner. At $5 per gallon that would mean
> $600 would run the A/C for 240 hours. At most that would be a
> couple of years for us, and probably less. We will be traveling to
> the East Coast in August, and are likely to be in hot weather until
> we leave Florida in November.
>
> I'll be sorry if it turns out that I have a leak somewhere else,
> but I'm fairly confident that I don't. The tech put plenty of
> fluorescent dye in with the refrigerant, and nothing has shown up
> anywhere.
>
>

[Don Bradner]

Did they put dye in yours when charging? I can see how that can be/will be a
great help in finding a leak, if I have one other than what I already knew about
and they fixed.

On 5/31/2008 at 5:58 PM Pete Masterson wrote:

>When I got my coach, the PO had converted the chassis AC to R134a but
>it wasn't working. When I had my radiator work done, I also had the
>AC serviced. Took $$$ of R134a. Worked ok, but not great. About a
>year later, it wasn't working quite so well. (No leaks were found at
>the time the system was recharged -- but, I wonder, are there
>inaccessible hoses where a leak could be hiding? In any event, I'm
>now at CCW in Riverside having several things attended to -- and I'm
>thinking about recharging the AC again ... but I'm not sure I want to
>spend another $600 or so on R134a...
>
>I did add a $12 oscillating fan that plugs into the cigarette
>lighter. It actually does a great job in keeping me cool until the
>coach warms up enough to turn on the genny and the roof-top units.
>Often, my heat discomfort is mostly from the radiant heat affect of
>the sun beating into the "fishbowl" up front more than the ambient
>temperature in the coach being too warm...
>
>Pete Masterson
>'95 Blue Bird Wanderlodge WBDA 42
>aeonix1@...
>On the road at CCW in Riverside, CA
>
>
>
>On May 31, 2008, at 11:36 AM, Don Bradner wrote:
>
>> There've been a few A/C discussions in various threads recently -
>> must be a calendar thing. I thought I would add my own.
>> <snip>
>> I know there are a number of folks who have posted that their dash
>> air does not work, and they just use the generator/house air
>> solution. We considered that, but even with the high cost of repair
>> the economics appear to be in favor of the repair route. Our
>> generator pulls about 1/2 gallon per hour when doing light work
>> like a single air conditioner. At $5 per gallon that would mean
>> $600 would run the A/C for 240 hours. At most that would be a
>> couple of years for us, and probably less. We will be traveling to
>> the East Coast in August, and are likely to be in hot weather until
>> we leave Florida in November.
>>
>> I'll be sorry if it turns out that I have a leak somewhere else,
>> but I'm fairly confident that I don't. The tech put plenty of
>> fluorescent dye in with the refrigerant, and nothing has shown up
>> anywhere.
>>
>>
>
>------------------------------------
>
>Yahoo! Groups Links
>
>
>

[Pete Masterson]

Yes, a florescent dye was used in the recharge process. The service
provider claimed to have carefully examined the system and did not
find any leaks. Between the time the PO traded the coach in and I
bought it, it had sat on various dealer lots for about 6 months -- so
the initial recharge may have reflected loss of refrigerant due to
failure to run the system.

As I recall from several autos I've owned, you're supposed to run the
AC (in winter) every 30 days or so to keep seals tight so the
refrigerant doesn't leak out. I may have failed to do this during
this past winter as I did not keep track of the dates that I
"exercised" the coach and I may have forgotten to turn on the AC
(which is easy to forget when it's 45 degrees out side...)

Pete Masterson
'95 Blue Bird Wanderlodge WBDA 42
aeonix1@...
On the road at



On May 31, 2008, at 8:56 PM, Don Bradner wrote:

> Did they put dye in yours when charging? I can see how that can be/
> will be a great help in finding a leak, if I have one other than
> what I already knew about and they fixed.
>
> On 5/31/2008 at 5:58 PM Pete Masterson wrote:
>
>> When I got my coach, the PO had converted the chassis AC to R134a but
>> it wasn't working. When I had my radiator work done, I also had the
>> AC serviced. Took $$$ of R134a. Worked ok, but not great. <snip>

[barry boyette]

Hey all. I'm new to this forum, been lurking for a while; but, thought I'd throw my $.02 in. Adding freon and doing a little of your a/c work is really no big deal. For example, make sure your condenser is clear of dirt and debris. It must flow air to work.Then, locate the big hose coming into the a/c compresser on the engine. The compresser is mounted to the front of the engine and has a fan belt that turns it. There are two hoses coming out of it. The big one is the low pressure side and the little one is the high pressure side. The low or big one should be cold and have water droplets on it when running and the high side will be hot to the touch.

While under there looking around, locate the service port which should be on the low pressure (big hose) somewhere. It looks like a valve stem for your
tire. That is where you put freon in. The little hose or high side should also have a service port on it. Never add freon here. The high side port should only be used for checking the high pressure when utilizing a set of a/c gauges.

Wal Mart sells kits for adding freon that has a little gauge included. Attach thehose to the low side service port with the engine cut off. Look to see what the pressure is with engine stopped. A good rule of thumb is the static pressure should be about the same as the outside ambient temp. If it's zero then you need to find someone that can service your system from scratch. If it's got some pressure on it then you can probably proceed.

Locate the freon site glass. You will need to watch this while adding freon. Next, start the engine and turn the a/c on. Look to see if the
front of the compresser is turning. If you're not sure shut the motor off and look at the front of the compresser while it is off. Now, restart the engine and check to see that the front of the compresser is turning. This lets you know if the clutch is kicking in and trying to circulate freon. Sometimes, you have to put a little freon in before the clutch kicks in. Simply open the freon valve and let some of it into the system. Some people hold the can upright and some upside down. I like to turn it upside down because it gets into the system quicker without trying to freeze up the can. Continue adding freon and watching the sight glass at the same time. If the system is low on freon the sight glass will have bubbles in it. They look like they are racing by at light speed. If you have converted to 134A stop putting freon in when the bubbles are almost gone. If you are still using R12 or one of its
cousins, keep adding until the bubbles are gone. While you are adding freon the blower will start to blow colder air. Depending on the charge in the system it could take several cans to fully recharge. It's probably better to have to little freon than to much. The low side when full of 134A should read between 14 to 35 pounds on the gauge give or take. A lot can influence this like outside temp and how much air is flowing across your condenser up top. On our crop dusters we have installed double condensers with double fans and we are seeing low side pressures of 10 - 15 and high side a little over 100 pounds even on a hot day. The condenser is the secret. Keep it clean and make sure it's flowing air.

When we started fooling with a/c on our crop dusters we didn't even know what the condenser did. Now we build our own systems using off the shelf parts for big trucks and ambulances. It
is a little scary at first but there is not a lot to it. Spending 600-700 dollars recharging a low system is highway robbery when you can do it yourself for $50 or less.

One other thing, I've found over the years a lot of differences of opinions when it comes to air conditioner work. What works for me may not work for you. If you have specific questions feel free to email me with your questions.

barryb

[Fred Hulse]

Barry

Thanks for the mini clinic on air conditioning recharge.

Well done!

Fred & Jeanne Hulse
Morristown Arizona
1997 Wanderlodge WLWB41

[Curt Sprenger]

I'll 2nd that. THANK YOU!

On Sun, Jun 1, 2008 at 8:54 PM, Fred Hulse <"fhulse@wildblue.net"> wrote:

Barry

Thanks for the mini clinic on air conditioning recharge.

Well done!

Fred & Jeanne Hulse
Morristown Arizona
1997 Wanderlodge WLWB41

--
Curt Sprenger
1987 PT38 8V92 "MacAttack Racing"
Anaheim Hills, CA