Too-Much-Hot-Water Solution

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July 10, 2012

Too-Much-Hot-Water Solution

Bob, I’d like to respond to “Too Much Hot Water” in the January 2007 issue of Highways. I too had this same problem of hot water coming out the cold-water system. I have an outdoor shower that has the hot- and cold-water valves, and it also has a shutoff valve on the showerhead. If the hot- and cold-water valves are left open and the showerhead valve is shut off, the hot water will get into the cold-water system there. Solution: Make sure all hot- and cold-water valves are shut off on any of the indoor and outdoor showers that have this showerhead valve. I hope this will solve Roy Morgan’s problem.

Dale Chappell
San Diego, California

Bob: Good point, Dale, and I received a number of letters and e-mails with this suggestion. I suppose hot water can be pushed back through the system if the mixer valves were left open on the outside shower faucet. But it seems to me that you would have water leaking out of the showerhead. Most cutoff valves at the showerhead allow for water to trickle out when closed. That being the case, you should notice that water is leaking down the sidewall of your rig.

I also received a letter from a reader who suggested that a bad gas valve and pressure-relief valve could also cause hot water to back up into the cold-water line. In this case, if the gas valve does not shut down when the water is up to temperature and that could also be caused by a bad ECO hi-limit switch the water will be super heated. Then if the temperature and pressure relief valve (T&P) fails, the heat is transferred to the cold-water lines. It’s highly unlikely both the ECO switch or hi-limit and T&P valve would fail at the same time. I would think the tank would rupture first, which, of course, is a very dangerous situation. I appreciate all the responses to this problem.

Finding a Portable Air Compressor

The value of maintaining proper tire inflation is a well-known fact.

I have been though two portable air compressors, rated for well over 80 psi. One compressor advertised for large truck tires was purchased at Camping World. Neither unit worked.

Finding an accessible gas station with air that would reach the 80 psi level is impossible. Plus the cost versus the time keeps me racing around the vehicle trying to achieve an impossible goal.

What specification do I need to look at to know a compressor will achieve the 80 psi level?

I would like to purchase something, but the size and weight of the unit are of obvious concern considering the limited storage in my 30-foot fifth wheel. Do you know of any portable units that will work?

Doug Cowie
Estero, Florida

Bob: Check out the new Viar 400P-Automatic. This portable (12-volt DC) compressor has an automatic shut-off feature that extends the duty cycle. This feature is very helpful when you have long run times to fill a tire like those on RVs. With the automatic feature, you can multitask while the RV’s tire is airing up.

The 400P is capable of a maximum working pressure of 150 psi and has a service-station-style inflation gun with a dial gauge. It all fits into a handy bag. I’ve used Viair products for some time and I am impressed with the quality. You can get details at or by calling 949- 582-6868.

Drain Doesn’t Drain

We have a 2003 Coachmen Clipper with a slide-out, shower, toilet, etc. Everything has been quite good on the unit (we bought it used) after I repaired a few items, but we still have a problem with the sink drain. It doesn’t!

I talked to the manufacturer (someone at the company), and they said it must be the routing. Well, I’ve rerouted until I am blue in the face. A trailer serviceman made the comment that Coachmen had this problem, which I find hard to believe. If we use a toilet plunger (new and dedicated to this sink), it will push the water through (actually seems to create a siphon effect). Do you have any suggestions? I am at wit’s end on this one.

P.K. Sims II
Dearborn Heights, Michigan

Bob: Take a look at your drain-pipe vents. If they are clogged, the sink water will not drain properly. The vent pipe could exit through the roof, or an interior vent (with check valve) could be installed under the sink, near the P-trap, which I assume you also have and is not plugged. If the vent goes through the roof, pull the cap and inspect for bird nests or other debris. It’s possible that your rig was designed to have an interior vent under the sink and it was inadvertently left out.

Parasitic Power Drain

We currently have a 2001 Rexhall Aerbus on a Ford chassis. After trips of any length, we plug into shore power at home and push the disconnect buttons. After two weeks or so (if we don’t start the motorhome) the engine battery is drained to the point it will not start or even turn over. We must use the batteries from the generator to start the RV.

Please help. If it is plugged into shore power and the battery-disconnect buttons are pushed, why is our battery being discharged?

We are new to RVing and we just love it. There are no better people in the world than fellow RVers.

Bruce and Peggy Haywood
Lampasas, Texas

Bob: There’s probably a parasitic drain on the starting battery. The CO detector can be wired to the starting battery and other devices, too, such as the memory portion of your in-dash stereo. I just heard from a reader who found that leaving the cruise-control switch in the on position created a parasitic drain on the starting battery. You never know how the manufacturers will wire their rigs.

When you use the battery-disconnect switch, it normally cuts off power from the house batteries. When you’re plugged in, the converter keeps the house batteries charged. It normally does not charge the starting battery because it’s been isolated from the house batteries.

You could install a battery isolator that allows the starting battery to be charged, or more simply, just add a knife switch at the starting-battery terminal. Then when you put the rig in storage, you can open the switch and the battery will no longer be drained by parasitic loads. While the knife switch works, a better choice is a Perko switch (commonly used in the boating industry).

Don’t get lulled into complacency by the knife switch. The battery will self-discharge over time. If the rig is in storage for longer than a month, I suggest that you charge the batteries with a good quality multi-stage charger (which is more efficient that leaving your rig hooked up to electric and depending on the converter). That will prolong battery life.

I certainly agree with your observations about fellow RVers!

Dinghy List

We would like to tow a vehicle behind our RV, which is a Fleetwood Tioga Class C. We have tried the tow-dolly approach, but that didn’t work for us. We have decided to tow a vehicle four wheels down (we have a 1998 Ford Windstar minivan), but are confused about which makeand model of vehicle can be towed this way without modifications. We have heard Saturns and Jeeps work; is there a comprehensive list of vehicles available?

Myron Klein
Olathe, Kansas

Bob: MotorHome magazine publishes an annual dinghy guide that lists virtually all the vehicles suitable for towing on all four wheels without modifications. This year the guide was distributed with the February issue.

You can also check it out by logging on to the MotorHome website,

Keep in mind that you can also tow a number of other vehicles on all four wheels by using drivetrain modifications, like those marketed by Remco. You can get in touch with Remco at (877) 645-7171 or online at


Pumping Tubing

Staying fit on the road presents a number of unique challenges. Access to gyms is limited, and storage requirements typically dictate that heavy barbells and weight machines be left at home. And no doubt many of us need to be working off the good life while traveling and socializing in our rigs.

The Versastick resistance trainer is a good way to hold on to those yearly resolutions to get in shape—or at least work off late-afternoon socials and evening potlucks. The whole kit fits in a compact bag that includes a two-piece bar, three lengths of resistance tubing, a door anchor and a carabiner—and it weighs practically nil. But you can’t discount the simplicity; this is effective exercise equipment.

To use, connect the bar and attach the resistance tubing via the clips on each end. Each piece of tubing has a different resistance value—from light to heavy. If you need more resistance, you simply clip on the second or third length of tubing at the same time.

The easiest method of providing the necessary resistance is to place the tubing under your feet. A door anchor can also be wedged in a door jam and connected to the tubing using the carabiner. This gives the user additional exercise positions but may not be practical for use in an RV unless the door is beefy enough to handle the resistance.

Excellent written instructions and a well-done DVD provide great information, including fitness and nutritional suggestions and workout programs (including core stability and cardio resistance). For safety reasons, the instructions must be followed precisely. Versastick is available online ( or by calling 888-938-3772. It sells for $79.95, which isn’t a high price to pay to stay fit on the road.

Leave a Reply


  1. Glenn Lacewell

    TO MUCH HOT WATER: If a coach has a hydronic heating system (Aquahot Hydrohot or Hurricane) the cold water lines can run in the same channels as the heater suppy lines and transfer the heat to the water lines. This can lead to hot water in the toilet, cold side of faucets and even the ice maker.

  2. Pamela Lane

    We keep our fith wheel pluged into shore power at all times, so my fridg can run, and also to run the aircondioner about once a month, I check my battery all the time to make sure it is okay. I would like to if this is wrong thing to do?.

    Good Sam says: I have forwarded your question to Tech Topics. You may also want to check out the forums as they are a great resource for information:

    You will need to be registered to be able post or ask questions. Our members are very helpful, and there may already be a topic regarding your questions.

  3. That certainly sounds like something very pleasant! I have forwarded this post as an email to [email protected] for further assistance. -WR

  4. Sandy Jaeger

    We have a 2006 winnabago voyage and recently we have been having problems with our shower pressure and hot water. When wanting to use shower the hot water is so hot that you almost have to shut it off when adding cold water that all you get is a trickle. Is there anyway to lower the temp of the hot water so when adding cold that there is still enough pressure to take a shower? thanks

    Good Sam says: That certainly sounds inconvenient at the least and dangerous at most! I have forwarded this post as an email to [email protected] for further assistance.

  5. Bev Aicken

    My husband and I just purchased a brand new 2011 Sydney Outback 5th wheel. This is our 6th 5thwheel, so we are not new to them. This unit is beautiful and has everything we want for living full time.The problem we are having is that when we run the cold water tap in the bathroom sink..we get a nasty sulpher odor from the water…doesn’t happen at any other taps. Any ideas on what may be causing this? Really appreciate all the helpful tips on this site…have a great Camping Day

  6. Oscar Underwood

    I’m surprised that you are not informing people who are having tire blowouts that they might have warped wheels. I had one blowout with 10 ply Mischelin tires at 20,000 miles and another at 22,000 miles. I was ready to contact a Michelin rep. when the tire dealer put a new tire on my wheel and put in on the balancing machine. As I was standing in front of the machine I saw that the wheel was warped. I jacked the back of the camper van up, started the engine, put it in gear, and knelt down beside the rotating rear wheels with a long screwdriver extended from my knee to the outside edge of the wheel and found that I had 3 warped wheels. One was warped as much as 1/4″. I purchased 3 new wheels and found that one of them was warped and had to return it for a replacement. The warped wheels cause the plies to separare and thereby cause a blowout. Maybe this info will help others.