[infoseek]

Originally Posted by EASYTRADER

I have a carrier APU, which is basically the same as a ProHEAT, and it has been nothing but a nightmare for me. Having said that I have learned a few tips, from NON-Carrier dealers as to why they are crappy, and what can be done to make them work better.

Tip 1, From Applied Industrial Technologies - "This thing has the wrong belt on it!!!"

We all have had problems with belts breaking on the generator drive, so the last time it happened rather than go to a carrier dealer, I tooled around on the internet and found this company, which has offices throughout the country. I sang the blues to the guy behind the counter so he came out and took a look at my APU setup, and immediately told me my belt was wrong for the application outside of its torque range or something like that.

he suggested using a 5VX470, or a GoodYear BX44 with notches. He had the Goodyear belt in stock so I bought a couple of those, he highly recommended the 5VX belt but he didnt have any in stock.

Tip 2, This came from the same place, they also sell bearings.

Proheats and Carriers have a tendency to BLOW the Generator bearings. Carrier told me this was caused by having the belts to tight. Applied Ind. told me this problem is almost always caused by improper pulley alignment, he showed me some pictures of bearing failures and there causes and sure enough I found a picture that looked like my failed bearing set.
They usually stock the bearings so when your generator blows it bearings again save 1700 bucks and buy new ones from them.

He suggested using a bubble level as a straight edge to line up the two pulleys, the straighter they are the longer your belts will last, the apu will run quieter,, and the generator bearings will last longer.

Tip 3, Gathered from lots of internet reading and a little gamble.
R-22 is not appropriate for use in a vehicle. R-22 has a small molecule and needs to compress at a fairly high pressure, It cools great, but in an environment full of vibration it will leak out and every 6 mos you will need to take it in to top it off. Its effectiveness also drops off quite a bit when outside temps rise above 90 degrees. A month ago, I blead all the r-22 out of my system and replaced it with ES-22. The new refrigerant doesn't require a license to install, requires 30% less head pressure to compress, and doesn't lose its ability to condense above 90%, in my experience it actually blows colder in high outside temps than lower ones. If you install it, your suction pressure should be 5lbs less than the ambient temp measured at the condenser but not higher than 90. So if its 70 degrees outside, your suction pressure should be 65, if its 110 outside your suction press should be 90.

I noticed a couple of things immediately upon replacing the refrigerate,
I read a 30 degree temp drop from intake to exhaust, with r-22 it was always less than 20.
The generator quieted down, I suspect this is from the AC pulling less electricity than it did before, because of the lower head pressure.

Also should it leak out again, I can top it off myself without a license.

Tip 4, Lucas Oil Treatment - this seems to quiet the clanking that comes from the kubota engine, my next experiment will be to adjust the idle down.

Just wanted to put some information out there with regard to refrigerants. First off familiarize yourself with EPA’s website on refrigerants and how to handle them. While it may not require an EPA certificate to purchase some of these chemical products, EPA requires a certification (section 608 and 609) to properly handle refrigerants in these environments. Another thing to note is that these substitutes while sounding like a great solution are mostly hydrocarbons and thus illegal to use as replacement refrigerants in most applications per EPA. EPA touches on the possible event that a hydrocarbon leaking into an enclosed compartment can cause explosions due to the flammability of the product. I would suggest that anyone considering making retrofits to A/C or refrigeration systems should consider the pro’s and con’s. Are these retrofit refrigerants approved by the EPA? Will these refrigerants void the manufactures warranty? Am I qualified by law to handle refrigerants? Who has certified these refrigerants? Please be aware of the legalities and dangers before moving forward. You can research this information on the EPA’s website. Hope this helps and here is a link to this information.

Common Sense in Protecting the Environment Without Endangering Safety - A Warning to Consumers About Hydrocarbon Refrigerants | Ozone Depletion - Regulatory Programs | U.S. EPA