My wife was helping me dump the blackwater holding tank in our motorhome a while back and since we had no way to hook up a water hose to rinse the tank, we were using a 5-gallon jug with a good size lid. Unfortunately, she was holding it too close to the toilet when the lid came off and dropped into the holding tank. I tried to flush it through the pipe but nothing came out; it still seemed to dump okay at that time. Several months later, this incident came back to haunt us when the dump valve was opened and no solids came out — only a little liquid. And, you guessed it: The black tank was almost full. I’ve contacted a couple of local dealers who reluctantly said they could fix the problem, but I can’t get an appointment for five months. We have several trips planned during that timeframe. Any ideas how to get out of this crappy situation?
—Rob Martinez
Rob, that’s a tough one. Over the years, I’ve seen a lot of strange things that were dropped into the holding tank, including the more common malady when the manufacturer cuts a hole in the tank for connecting pipes and leaves the 3-inch cutout in the tank. Of course, when they just leave it in the tank, flow problems will rear their ugly heads down the road — always at the most inopportune times.
Unfortunately, at this point there’s probably no way to retrieve the cap easily. While you didn’t mention the brand of the coach, nor the plumbing configuration, hopefully you can get to the dump valve and remove it. If it’s close enough the holding tank you’ll be able to get in there with a flashlight and some kind of a hook (a bent wire clothes hanger could suffice) to maneuver the lid and pull it out. This, of course, can get quite ugly. If possible, enlist the help of a honey dipper (mobile pump-out service) to hook up to your sewer termination and possibly suck the lid out. In case the honey dipper operator is not familiar with RVs, have someone hold the foot pedal on the toilet open to help with extra ventilation during the dumping process (to prevent collapsing the tank). It’s also possible to backflush the black tank with water being released from the gray tank while dumping, but that’s iffy.
It might even be better to find someone who pressure-cleans holding tanks. Inserting the long wand right into the tank might push the lid aside long enough to flush out the holding tank. Once it’s clean, you’ll have a better — or, at least, less messy — chance of fishing the cap out. If all else fails, the tank will have to be removed, which isn’t pretty, either. Good luck.
I have a 1999 Coachmen Class A motorhome with two air-conditioners and a four button Duo-Therm (Dometic) thermostat that also controls the furnace. Recently, when I turn on the thermostat the display works — but when I push one of the mode buttons everything goes out. I took the thermostat apart and everything looked good; I didn’t see any burned connections and the On/Off switch seemed to work properly. Still, the thermostat doesn’t work and might need to be replaced. I looked online and could not find a replacement with the four buttons. It looks this thermostat has been replaced with a five-button unit, which is completely different, so I’m not sure it will work with my system.
—Mike Zelinski
Mike, unfortunately Dometic stopped making the four-button thermostat a long time ago. At this point you have two options. The first option, which would probably be the most reliable, is not cheap: You can buy an upgrade kit to a five-button thermostat, (part number 3310014000), which is available online and in many RV parts stores; it sells for $400-500. The conversion kit from four to five buttons requires wiring — and the control board in the air-conditioning unit will need to be replaced. If you have two air-conditioners, you will have to tie the second one to the first one with a communication cord, which looks like a standard phone extension cord but the plug-ins are reversed.
Another option will take a little effort on your part, but is a good solution for a whole lot less money. If you go to ebay.com and search for “Dometic 4-button thermostat” you’ll be led to a company (AceQuality) that replaces the four buttons on your unit. Apparently, these buttons cause the failure 90% of the time. The company does not sell new or refurbished thermostats and is very clear in its description that it only provides a service to replace the buttons. You’ll have to send the defective thermostat — a mailing address is clearly noted on the listing — to the company. The buttons will be replaced and the thermostat sent back to you. The cost for replacing the buttons is $99.99 and the work is warranted for one year.
Of course, you can also install two separate thermostats, one for the air-conditioner and one for the forced-air furnace, but that gets a bit trickier with the wiring and not worth the effort, unless your old thermostat cannot be fixed by replacing the buttons.
I have a 2016 motorhome with a Dometic five-button thermostat and I am unable to make the Zone 2 air-conditioner to work; the Zone 1 unit and the furnace work fine. I’ve dropped the air-conditioner ceiling assembly and I cannot see anything except for all the wires that are hooked up. Now I’m at a loss. Do you think the thermostat is defective or do I have a problem in the air-conditioner itself?
—Mike Hill
Mike, the starting point is to reset the thermostat and to see what happens. Depress and hold the Mode and Zone buttons and while holding them down, turn the On/Off switch to On and then release the buttons. You should see FF on the screen momentarily, indicating that the thermostat has been reset. At this point you should still see Zone 1 and 2; if you do not see Zone 1 or Zone 2, it just means that the thermostat is not communicating with the air-conditioner(s).
The most likely culprit will be the communication cord that runs between the two air-conditioners. If you do not see a Zone 2, that will indicate that the communication cord may be defective. There is a remote possibility that the control board is defective, but unlikely.
If the communication cord is defective, you can purchase a new one online and, without taking everything apart, run this cord temporarily between the air-conditioners and see if that solves the problem. If it does solve the problem, now the fun starts; your only chance to conceal the cord will likely be through the ducting.
A good solution, if you determine that the thermostat is defective, is to replace it with one from Micro-Air (microair.net). The company’s EasyTouch RV thermostat will modernize your system with Wi-Fi and Bluetooth capabilities, which allows for remote control of the air-conditioners. Micro-Air offers a direct replacement for the Dometic Comfort 5 Button thermostat for $249. The EasyTouch thermostat is nice looking and easier to read.
Micro-Air is well versed in the RV air-conditioner space and started its journey with the EasyStart air-conditioner soft start system, which reduces power requirements and is very popular with boondockers who rely on portable generators.
Recently we were camping in a very rural campground that didn’t even have phone service and I had to back in between RVs on one side of the road and couple of big pine trees growing in the absolute wrong place for maneuvering the trailer on the other. Unfortunately, we did not have two-way radios, figuring we would just simply use our cell phones with mine connected through speakers in our new truck. My wife went outside to help but did not quite understand what I needed her to do; she was constantly nowhere to be seen and, of course, I couldn’t hear her 45 feet away in the cab of the truck with a diesel engine running. Do you have any suggestions that I can relay to my wife?
—Robert Sinclair
Here are a couple of tips that might help: Explain to her that if she can see you in the mirror then more than likely you can see her unless you’re on an extreme angle. Teacher to use her arm and hand rather than just finger signals, which a lot of people tend to do; fingers only are difficult to see. If the arm and hand are moving in a big arc or side-to-side in a straight line with a finger pointing, it makes a huge difference when you’re trying to see 40 feet behind you. Teach your wife to physically move side-to-side periodically to check the other side just in case there’s a rock or a pipe sticking up that you cannot see. Your job is to stop and wait for her to come back into view in the mirror on the side she’s directing you. Don’t be afraid to get out and say, “Honey, I can’t see you and I’m going to stop and wait for you to come back into view. If you don’t see me moving after 30 or 40 seconds, then I may not be able to see you well enough to continue backing.” Always use the cell phone when service is available but continue to use hand signals at the same time. It may also be wise to invest in a pair of two-way radios (“walkie talkies”). to also use in conjunction with hand signals. Since, as you discovered, cell phone service isn’t guaranteed, inexpensive two-way radios with hands-free operation and extended range (and thousands of five-star ratings) like those from Moico can be found on Amazon for less than $30. That’s a small price to pay for eliminating any possible bruised feelings with a traveling companion.
One more thing: During the learning period, get out of the truck numerous times to make sure your wife is guiding you properly. Remember, she is new to RVing and it will take some time to learn how fast the trailer reacts to turns and how much space is necessary to make those turns. Trust me; acclimation will take a little time, but the results will be worth it.