Anti-Ant Attack
Regarding the “Ant Infestation” letter in the August 2009 Tech Talk column (page 20), we have on several occasions also been infested with ants. We have found Amdro Ant Bait Stations the quickest and best way to get rid of them.
Michael & Elba Matherne, F244366, Davenport, Florida
Thank you for sharing this information.
Dish Pan Holding Tank
I do not agree with your answer to leave the gray water valve open at a campground (September 2009, “Toilet Paper,” page 22). The normally slow release of water will let food deposit on the tank bottom and not flush out. It is best to let it fill and dump with a rush that will flush the tank properly. If the black tank is also allowed to fill completely, it will dump properly as well.
Elvin Shaw, F253866, Mesa, Arizona
I agree with you on the black tank, but I don’t completely agree on the gray water tank. After more than 40 years of RVing, including several years as a full-timer, I never suffered from food residue in the gray water tank. The water from the shower and the lavatory and galley sinks have kept everything flushed out nicely.
I certainly am not suggesting that there’s anything wrong with keeping the gray water tank closed while camping and allowing it to fill. When dumping, the water flow from a full tank does sweep away deposits that could accumulate on the bottom and keeps the valve seals clear. Also, when keeping the vent open, there’s a chance of sewer odors escaping through the roof vent, which could lead to an unpleasant campsite environment.
“Frozen AC” Responses
I read the “Frozen AC” letter in the September 2009 issue that described air conditioner freezing problems experienced by Mr. Giannakopoulos (page 23) and thought I would mention something that happened to me. I recently replaced a Duo-Therm air conditioner that had been damaged by hail. After the installation I also experienced the loss of cooling and the freeze-up problems mentioned by others. As this had never happened with the old units, I went back to the shop that installed the new air conditioner. We tried all the fixes mentioned in the article, with no luck. Our mechanic still had the original unit, and when we compared the old with the new, we found a “freeze sensor” mounted on the old unit. It is located by the coil and plugs into the central control unit. Once we installed the old sensor into the new unit, the problem was fixed. The supplier of the unit said that the sensor is not included with the replacement unit but can be ordered separately.
Your readers should check the wiring diagram included on the central control unit and determine whether a freeze sensor provision is included.
Steve Robertson, Oak Ridge, Tennessee
I had the same problem as Mr. Giannakopoulos in the rear air-conditioning unit of our 2005 Holiday Rambler Neptune. The unit wouldn’t cool the motorhome and would freeze up and ice over, which would then melt and drip on the bed. The dealer checked it and said it was fine and working okay. The factory in Oregon checked it and said it was fine and working okay. The problem existed for almost four years. A few months ago I asked my WesTex chapter RV buddies about the matter, and they explained that there is a wired probe that controls the recycling operation and should be securely stuck into the coil fins. Sure enough, I pulled the cowling and there was the wired probe hanging loose. I checked the front air conditioner to verify what I had found and located the approximate probe placement. I secured the wired probe in place, and now all is well. The air conditioner runs continuously and cools properly, plus there’s no more ice.
Dan Ives, F307391, Rosenberg, Texas
Thanks to both of you for sharing this information.
Batteries
In the September 2009 “Tech Talk” column, Gerald Fenno sent in a letter saying that his solar charging system fails to charge his chassis batteries as the coach sits in storage. I also suspect that shore power may not charge the chassis batteries, as was the case with my coach. I had the same problem, further complicated by the radio and CD player being connected to the chassis batteries. My solution was to purchase a Trik-L-Start from LSL Products (www.lslproducts.com; 877-257-4655), a small device that cost about $50. It was easy to install, with good instructions and over-the-phone technical support. The device bleeds power from the house batteries to the chassis batteries, which, in effect, balances the charge between the two sets of batteries. My house and chassis batteries are going on 7 years old. The batteries have never been equalized (solar panels eliminate the need to do so), and since I installed the Trik-L-Start four years ago, I have never had either set of batteries less than fully charged when coming off of multiple months of storage.
Tom Mosher, F228131, Spokane, Washington
Thank you for sharing this information.
More MPG
In Mr. Brightly’s “MPG” article, which appeared in the September 2009 issue of FMC magazine (page 40), he stated: “Prior to installing the Airtabs, my motorhome’s engine would have to turn 2,000 rpm to reach 55 mph. With the Airtabs in place, 55 mph was achieved at just above 1,900 rpm.”
I am certainly not a mechanical engineer, but my understanding is that with a transmission in a specified gear, and the same rear-end differential gearing, the speed is totally a function of rpm. In other words, how can the rpm changes at the stated speed of 55 mph? I don’t think it is possible. It may, however, take more power (fuel) to achieve that speed (I believe). While certainly not as sophisticated a test as the author’s, I have documented that our coach can average more than 9 mpg at 60 mph, while it gets only 6 or 7 mpg at higher speeds. A motorhome is more efficient as well as much safer at the lower speeds.
Thank you for all the great articles.
Ed Koch, F385573, Greenfield, Indiana
This would be true if the motorhome had a manual transmission, with solid metal gears and not a fluid coupling as is in an automatic transmission. The Airtabs did in fact cut the engine rpm by approximately 100 revs.
Cracked Tubing
I installed a Dometic refrigerator in my motorhome five years ago, and the boiler tubing recently cracked. Dometic had a recall on their refrigerators in 2006, but I never received a notice. I am changing out the cooling unit, which I already have removed. Can you tell me whether the RV Cooling Unit Warehouse — units furnished by Amish Manufacturing and sold by David Force — is a reputable company? I couldn’t find an address for them.
Marvin Middlebrooks, F127056, Fort Worth, Texas
I cannot endorse or recommend a company with which I have not had personal experience. The Web site for RV Cooling Unit Warehouse (www.rvcoolingunit.com; 901-337-9948) is impressive, and it appears that the company offers a three-year warranty on rebuilt cooling units. Apparently David Force and his family have been in the RV repair business for many years, so you should be able to find out whether the company has had any problems by calling the Better Business Bureau in Memphis, Tennessee.
If you install the cooling unit — new or rebuilt — I would recommend you follow the instructions provided (especially the final tilting of the refrigerator in all four directions to disperse the refrigerant to the bottom of the unit) before placing it in the cabinet.
Funky Fridge
I have a 1996 American Eagle with a Dometic side-by-side refrigerator. When operated on electric power, the freezer works fine, but the refrigerator will not stay cold. What’s really strange is that it runs fine when in the LP-gas mode. I replaced the thermistor and the computer board, but to no avail. Can you provide me with any other possible solutions for this problem?
Joe Bowling, F294104, San Benito, Texas
If the refrigerator works properly on the gas mode but not on the electric mode, the most likely suspect would be the 120-volt heating elements. The side-by-side style refrigerators have two heating elements, and if one is defective, there will be only partial cooling. To test the heaters, unplug the 120-volt-AC service cord and perform an ohms test on each heater. Disconnect the leads from the control board to test. Each should show approximately 70 ohms. The defective one will have a very high ohms number or be completely open (no reading). Replace the defective one.
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