A/C fuse?

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scottydl

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I'm chatting with a guy over e-mail (met through this forum actually) about an '84 Ford Class C that he has for sale.  He mentioned that the dash air does not blow cold which seems to be pretty common in these older rigs, but said he thought it was only due to a fuse somewhere behind the dash.  Anyone have any insight on this?  Seems to me that no cold air means either (1) a bad compressor, or (2) a leaky system.  But hey if it can be fixed with a fuse I'm all for it!  Thanks in advance -
 

Gary RV_Wizard

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I don't know of any fuse that affects the coldness (or lack there of) of the air.  Most likely causes are: (1) leaking or contaminated freon, (2) bad compressor, (3) compressor clutch not engaging or loose/broken belt, (4) failed temperature control valve.  1 & 2 are expensive repairs, 3 might be an easy fix or might be a new clutch, 4 is fairly expensive unless you just replace the automatic valve with a manual one.  The temp valve is the thing that regulates the flow of hot water through the air plenum in response to the temperature know/dial on the dashboard, thus changing the emperature of the incoming air. If the valve fails open, it is always re-heating the incoming air that the compressor just chilled and you never feel cool air.
 

John From Detroit

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Generally the same fuse that blows the air, cools the air.

I have seen a Ford product where it made cold, but no blow, turned out to be a bad connection at the blower motor (Fixed)

The same thing can happen at the compressor clutch

If you can locate the AC compressor you can easily check all fuses, here is how.. Put the old eye on the compressor and signal the other half to engage AC... Does the compressor engage? (Give it a minute or two) if so it's not a fuse
 

Mblaster

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All of the above plus a rig that old is probably using R12.
I don't think you can even buy R12 anymore.
All ac's now use R134. The ac would have to be converted.
IMO look for something newer that at least uses R134.
 

Alaskansnowbirds

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Mblaster said:
All of the above plus a rig that old is probably using R12.
I don't think you can even buy R12 anymore.
All ac's now use R134. The ac would have to be converted.
IMO look for something newer that at least uses R134.

You can still get R12. Our '93 van has R12 in it and I had it serviced about three weeks ago. R12 is getting scarce and expensive. $48 per pound according to the bill.
 

scottydl

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Mblaster said:
IMO look for something newer that at least uses R134.

If wishes were horses....

unfortunately something new enough to use R134 (mid 90's?) is not in the budget.  I'll have to settle with no working dash air if it comes to that.  Or have the older system converted to R134?  I've heard of that being done in classic cars, but I don't know much about the process or cost.  Many MH drivers prefer to leave the dash air off and run the generator and roof air anyway, right?  So I'm wondering if it would really matter.
 

John From Detroit

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Converting from R-12 to R-132A is fairly easy.  There are two schools of thought.  School one is simply replace the gas.  The procedure it this,  Using a freon sucker device totaly evaucate the system, Remove all the freon (this requires professional grade hardware) as it's valuable, very valuable, and sell it to a recycler.

Seal any leaks in the system (Most important) and do any other service needed to the system.  Purge it, Purge it well

Finally again evaucate the system and then refill with R-134A

The other school of thought says you need to replace all the hoses and seals (Basically anything NOT made of metal.

Note: this is not as expensive as it sounds by the way, there are not that many hoses (4 on most systems, sometimes just 3)

I would suggest contacting a professional ans asking about the process

Now, the bad news

R-12 systems will drop the temperture 30 degrees in most cases, so air entering the evaprator at oh, say 80 degrees, comes out around 50.

R-135a only drops 20 degrees for the same system, so you loose a LOT of cooling power
 

Gary RV_Wizard

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You can offer the owner the choice of either repairing the system BEFORE you purchase or giving you an additional $400-500 off for repairs, which must include conversion to R134a.  If he choses the latter, I'd keep the $400 to apply against other needed repairs and use the house a/c system instead of the dash a/c.

He can probably get it to cool for a short while by finding someone to simply refill the system with freon without fixing the problem (and that's illegal if there is a freon leak),  but that leaves you with a non-working a/c 30-60 days later. If he gets it repaired, make sure you see the receipts or better yet, be present at the repar shop.
 

Mblaster

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It can still get plenty hot in the cab of a class c with just the roof air on high.
I wouldn't even think of traveling w/out the dash air in my c class blowing cold.
Here in cali R12 isn't sold retail anymore.

Wanna buy my 94 Tioga 24. Time for me to get a A class.
56K miles,460, bunch of new stuff...works great, road ready. 15 thousand bucks.

Good luck what ever you do.

 

scottydl

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All great ideas/advice, thanks everyone.

Mblaster said:
Wanna buy my 94 Tioga 24. Time for me to get a A class.
56K miles,460, bunch of new stuff...works great, road ready. 15 thousand bucks.

Sounds great and yes I *want* to buy it, but over twice my budget at this time.  :p ;)
 

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