recharge roof a/c?

[Superdawg]

Well, we are going to the Colorado river next month and it has me thinking about the a/c unit. It blows cool but not cold. It is 9 years old and has never been serviced to my knowledge. I removed the roof cover and there is no recharging port, only a dead-end soldered copper tube. All the parts look good, just old. Is that where a fitting is soldered on to recharge the a/c?

Has anyone ever recharged their a/c unit? Did it help?

I have heard that about 20 degrees less than outside temperature is about the most you can expect.

I plan on putting that silver cardboard in some of the windows to reflect the heat, that will help. About 3-4 years ago, in a different trailer, outside temps were 115 and the inside of the trailer was 95 during the day. I'm hoping for lower temps with this one.

thanks all,

Tom

 

[AClayton]

Refrigerant does not decompose or lose its 'effect'... . if the unit needs to be recharged then the freon has leaked out. I would guess that your biggest problem would be the evaporator and/or condensor needs a complete cleaning. A thorough cleansing with coil cleaner and low water pressure will solve your issue. Depending on the acidity of your choice of coil cleaner,have someone else constantly dilute the wash off to prevent ruining the finish on the roof and sidewalls of your trailer. Do the coil cleaning 1st before having a qualified A/C tech re-charge the unit. it is very rare that any model A/C unit from any manufacturer does indeed suffer from a refrigerant leak. If the motor and compressor runs and amp out OK,I'm confident the coil cleaning will solve your cooling issue.



I believe RVTRKN is a certified A/C tech... . I know he will chime in and offer more advice. He frequents these boards regulary also!!!



Alan

 

[WilsonF]

There was a time that I wanted to have my A/C recharged, and I think it can be done, I just couldn't find anyone that would do the fitting thing.

Floyd

 

[Superdawg]

The quick replies and great information is much appreciated. Now more than ever, I am really trying to keep the change in my pocket.

I have never looked for coil cleaner. Would Home Depot, Lowes or Ace hardware carry it?

 

[RVTRKN]

Wash the condenser coil (the coil exposed with cover on) only with water then clean your indoor air filter. A normal home AC is when the entering temp is 20* warmer than leaving temp. However you have several fan speeds that will change the amount of air flowing across the evaporator that will change the leaving air temp and the 20* theory does not apply. Give me your Make and Model, make sure it is from the data plate and BTU if listed, I will research it for you, I'm a Dometic licensed retailer so I can get more info than most, if its Dometic. The process tubes are what those tubes are called, and they can be reused, but its complicated and I recommend a certified tech do the work. If there is a leak and and is not an easy repair, I recommend you replace the whole unit, its just not worth the time or effort and it can cost you more than 60% of the worth of your unit.

 

[AClayton]

I have had good luck w/Simple Green,diluted of course. You do not administer the product too strong because of the finish on your RV. When I've cleaned them,I simply spray extra water over the roof and down the sides to prevent streaking from the chemical. Simple Green is powerful also, but diluted with water,it will be fine. Coil cleaner may be difficult for the avg. homeowner to purchase. Anyway,clean the coils 1st and if that doesn't help at all and your unit is struggling to maintain setpoint,then get your unit re-charged or as RVTRKN stated... . replaced.



Alan

 

[Superdawg]

Thanks for all your suggestions. I ended up cleaning the outer radiator w/ 409 and water, using plenty of water to wash it down. I have an aluminum skin roof, not rubber.

I opened up the unit and looked at the inner radiator. It appeared very clean so I closed it back up, sealing the joints w/ aluminum tape.

I cleaned the inner filter and replaced it.

Powered up the unit and ran it for about 20 minutes. It feels pretty cold to the hand, a little colder than before the cleaning. I don't think that recharging this unit would get it colder than this.

thanks to everybody that chimed in.

Tom

 

[AClayton]

Did a lot of dirt and grime come out of the condensor when you cleaned it?How about the filter?If so,that may have very well been your problem. Like I said,it is rare that these units leak freon. If you have pets and/or children running around in the RV or the exterior door gets a lot of use with people running in and out and such,filter cleaning intervals should be increased to compensate.



Alan

 

[AClayton]

Did a lot of dirt and grime come out of the condensor when you cleaned it?How about the filter?If so,that may have very well been your problem. Like I said,it is rare that these units leak freon. If you have pets and/or children running around in the RV or the exterior door gets a lot of use with people running in and out and such,filter cleaning intervals should be increased to compensate.



Alan

BTW,this regular filter cleaning applies to anybody who owns an RV and home for that matter. In the HVAC field,cleaniness and minute electrical problems make up a large portion of our 'service' calls and many can be prevented with simple preventative maintenance. For those of you already aware of this,please disregard my post



Alan

 

[MProctor]

one other thing to check is the voltage coming to the RV. Ive had some wierd problems with my A/C in some campsites.

 

[Skydiver]

AClayton pretty much summed it up. If you are getting 20 degrees difference from the suction (intake) air as compared to the discharge air don't touch it. Does you Air Cond work OK after sunset?

Our old 37' Newmar owners manual says "try to find shade when temps are high". The 13,500 btu unit will nearly freeze us at night, but anything over 85F or direct sun is not comfy.

.

Remember any type of cooling system does not cool anything. It removes heat. If it is not blowing heat from the condensor somethings wrong.

Good Luck.