|
|
RV Doctor ColumnRV Doctor #320 Dear RV Doctor, how hot does the boiler on the back of an RV refrigerator get? We have a 2-way (LP and 120-volt AC) refrigerator in our coach. This past weekend we tried to use the refrigerator on electric power and noticed that it was not cooling like it should have. That metal box on the back of the refrigerator was hot to the touch. It almost seemed too hot. The ambient temperature outside was also quite high. Rod Goins, ( Rapid City , SD )
Rod, the rear components of any absorption refrigerator will get quite hot. That's why correct leveling and proper venting of that heated air is so crucial for optimum operation of the cooling unit. Cleanliness also plays a part in the overall effectiveness of the operation as well. Extremely high ambient temperatures will lay a huge impediment on any absorption unit as it tries to transfer heat from inside the box. It's probably not realistic to expect inside temperatures to sink much lower than about 30-degrees below ambient in such conditions. Plus the heat buildup at the rear of the refrigerator will be amplified as well adding to the detriment. The boiler section of the cooling unit will always be the hottest under normal situations since that is where the heating element and LP burner are located. Blocked cooling units will experience hotter than normal temperatures at the absorber vessel and along the absorber coils as well, but typically the entire rear of the refrigerator will get quite warm. As long as you are level and there is a clear chimney effect behind the refrigerator, there's not much that can be done until the ambient temperature drops some. The addition of an auxiliary exhaust fan will help if you continue to experience such high temperatures. Also a battery operated fan inside the refrigerator will be beneficial for more even cooling throughout the storage compartment. Try not to leave the door open too long when surveying those tasty choices as I do when I'm searching for that late-night snack. Open the door, remove the object and close it right away. There could be a thermostat issue at work here, but not enough information was provided to delve into that. Chances are, the high ambient temperatures are the cause of the seemingly inefficient operation of the refrigerator.
Dear RV Doc, our rooftop RV air conditioner takes a long time to blow cool air. The air is not cold, only cool. Can RV air conditioning units be recharged like on a car, or do they have to be replaced? Edgar McPherson, ( Marathon , FL )
Edgar, all RV air conditioning systems can indeed be recharged, but usually as a last resort. And not all RV service centers perform this service, so you may have to call around first. Refrigerants must be contained and recycled. Federal and state guidelines are in place for the proper collecting, storage and resolution of the recovered refrigerants, so check in your area to be sure your service shop can indeed perform an evacuation, dehydration and re-charging of your unit. But first, be sure all else is in working condition. The fact that your unit blows some cool air may indicate a dirty filter or soiled and blocked fins on the condenser or evaporator. Have the unit correctly diagnosed prior to having it evacuated and recharged. A simple measurement of the amperage draw on the compression and a temperature differential measurement of the air going into and out of the evaporator will quickly determine if the sealed system needs recharging.
Dear Gary, we are buying a new 39-foot RV with two slideouts. My question is can you give some tips on what I should keep in mind for maintenance for these slideouts? Robert Runyon, ( Auburn Hills , MI )
Thankfully, Robert, there is not an extensive list of maintenance tasks required on most slide units. Obviously keep your eye on the top and side room seals, making sure they are engaged when the room is extended and retracted. There are a few aftermarket products available now for keeping the seals cleaned and maintained such as Protect All's Slide-Out Rubber Seal Treatment. Features like built-in UV protection, water repelling and anti-static characteristics make it the best resource for proactive care for all slide seals. Keep the slide mechanisms clean and dry, regardless of the type employed on your rig. Never use a moist lubricant like WD-40 on slide mechanisms; always use a dry lubricant to avoid attracting dust and dirt. Use the dry lube on all the exposed metal components. Always inspect the roof of the slide-out prior to retracting the room after any extended stay. You'll want to avoid dragging bird droppings, dirt and leaves or other debris into the RV on the roof section. If yours are hydraulic slides, be sure to monitor the fluid level and to periodically inspect all the hoses and fittings. Be sure each room "tracks" properly and that both sides extend and retract at the same pace. If either room is equipped with LP, electrical or plumbing umbilicals, insure their integrity from time to time. And as you'll get used to me saying, keep the battery charged!
Dear RV Doc, I could really use your help. I recently purchased a used, gasoline powered 1994 motorhome. When I got it home I found that the Onan generator did not have an exhaust on it any longer. I have been unable to find where to extend the exhaust. Neither the manufacturer nor Onan seemed to be able to help me. I don't know if the exhaust should be run to the side of the motor home or directly down underneath the coach. I have not seen another coach like it to inspect it to find how is should be extended. Clif McWhorter, (North Zulch , TX )
Clif, I am assuming the exhaust manifold and muffler are still intact and that you are simply missing the tail pipe extension, correct? Typically, the exhaust pipe is routed to the closest side or to the rear of the coach, whichever is the shortest run. It should not terminate directly underneath the coach. According to the ANSI standards, it must extend beyond the sidewall by one-inch and not terminate directly below any window that has the capacity to open. Also, it must not terminate within six-inches of any item that opens into the interior of the RV such as a storage compartment or entry door. You'll want to minimize the amount of turns the exhaust pipe makes. More elbows or turns in the piping increases the backpressure on the exhaust system. Be sure to support the exhaust pipe every two or three feet using appropriate tail pipe hangers of the correct diameter.
|
|
|
[ Home ] [ Ask the RV Doctor ] [ RV Doctor Column ] [ Memorandums ] [ Interesting Articles ] [ Product Spotlight ] [RV Service Technician Training ] [ Seminars ] [ Links ] [ Gary's Bio ]
Send your questions and comments to:
gbunzer@cox.net |
|