All posts by Dave

Tired of your RV Water Pump? Here’s a fix for it.

It’s been a while!  Between lots of work, travel, holidays, RV projects, etc., I haven’t written anything here in a while.  But this time I’m writing about something I wish I’d done a long time ago, before I was also fighting a water leak: getting rid of the noisy, pipe-rattling water pump that slows to a trickle if you try to run more than one thing at once, in favor of a more powerful jet pump.

In the past, I’ve talked about ways to make the regular RV pump work better, but a second diaphragm leak in as many years had me frustrated and looking for a better solution.  I decided to roll the dice on a  different approach–a jet pump meant for shallow well applications.

What’s different about a jet pump?

So first, let’s talk about the typical RV water pump.  It’s a positive-displacement, self-priming pump.  What that means is that for every revolution of the pump’s motor, same amount of volume is supplied to the RV’s plumbing system, largely independent of pressure. It’s basically a 3- or 4-piston/diaphragm single stage arrangement–the diaphragm opens, filling with water from the tank, then expels that water into the water system.  Being self-priming means that it generates suction when there’s no water in the pump housing itself.  In almost all RV applications (short of park models), they run on 12V DC power, drawing about 4 amps (~40-48W) running.  They usually cycle on and off with a pressure switch mounted to the top of the pump housing.  While they still cost about $100, the pump itself is all plastic.

A jet pump on the other hand combines a centrifugal pump with a venturi/jet arrangement. A centrifugal pump can be found in all kinds of applications, from the water pump on your car to the 9,000 hp pumps circulating water through a pressurized water nuclear reactor.  The centrifugal pump ejects water through an orifice that creates a venturi and draws more water in.  It’s continuous operation, as opposed to the discrete intake and exhaust cycles of each diaphragm in a normal RV pump, means it won’t rattle pipes and the water delivered to your fixtures won’t have the same pulsating effect you might be used to.

Pump Selection Criteria

Here’s what I was looking for:

  • Reasonably compact size.  I knew it was going to be bigger than the outgoing pump, but I didn’t want to lose more space than I had to.
  • Capability to deliver reasonable flow at reasonably high pressures.  Beating the old pump at a minimum, hopefully able to sustain enough flow in the shower while the washer tub fills.
  • Good for potable water.
  • Quiet(er).  Low bar relative to the old pump.

Let’s get the not-so-good out of the way first.  A jet pump isn’t going to be self-priming.  In other words, if we just hooked it up and turned it on, it would run without ever moving any water.  It also doesn’t come with a pressure switch, so we’ll have to add one in separately (as it turns out, this will end up being an advantage).

The particular jet pump I purchased is about the smallest I could find at 1/2-hp, with a stainless-steel impeller.  It’s rated at 960GPH peak flow–that’s 16 gallons per minute–and has no trouble with 55 psi.

What else is needed?

I already mentioned that the pump doesn’t integrate a pressure switch.  This is easy enough to remedy, either off the shelf at the local home improvement store or from Amazon.

Pressure Switch

Given that the pump is rated for 55 psi, I went with a 40/60 pressure switch.  But not just any pressure switch–this one has a lever on the side.  In addition to cycling on and off between 40 and 60 psi, as pressure falls, it will also open to prevent the pump running non-stop dry.  For a rig with washing machine and dishwasher, this provides some peace of mind that I won’t ruin the pump if I run out of water while not there to catch it.

.  It’s pretty cheap, and does the job well.  If you don’t have pressure in the system (say, first time or after you’ve run the tank dry) you have to momentarily hold the switch arm to start the pump.  After that, it takes over, and works unattended until you run out of water.

Check Valve

Unlike the outgoing RV pump, a jet pump like this doesn’t internally prevent flow backwards to the tank when the pump stops.  While the pump installation instructions called for two check valves, the minimal vertical distances between tank, pump and water system really don’t warrant it.  The check valve I used can be picked up at Lowe’s/Home Depot or Amazon for about $10.

Since we have two purposes, but only one valve, we need to locate it so it does both.  We want to prevent flow backwards through the pump, but we also don’t want to lose prime when the tank runs empty.  That means the valve needs to go on the supply to pump, not between the tank and the water system.

Plumbing Fittings

At the very least, you’ll need to run a line between check valve and pump.  You’ll also need to adapt the typical 1/2″ plumbing in the RV already to the 3/4″ inlet and outlet on the check valve, and the 1″ inlet and outlet on the pump.  A few lengths of PEX tubing and crimp rings, fittings, etc., will be needed depending on the space you’re working in.

Ok, so you tried it.  How well does it work?

It looks a little messy, but you can see all of the components here. Water comes in from each of the 3 fresh water tanks bottom right, up into the check valve, and into the right side of the pump. From there, it discharges toward the accumulator tank, pressure switch, and the rest of the potable water system.

Awesome!  Compared to what I suffered with before, it’s a huge improvement. It took more than I expected (about 24oz.) of water to prime, but I’ve only done it once.

Going from no pressure to 50 psi only takes a few seconds.  That includes building pressure against the 2-gallon accumulator in the system.  (You do have an accumulator, right?)  Yet it isn’t so quick that the pump cycles on and off while doing stuff.

I can also turn on more than one fixture at a time, without flow slowing to a trickle.  Someone flushing a toilet, or the dishwasher or washing machine filling no longer puts a shower on pause.  The pump definitely makes noise, but it’s an easily muffled noise–much higher in frequency than the old pump.  Maybe something along the lines of a blender, without anything in it.

I’ve also run the tanks empty a few times.  The pressure switch cuts power to the pump just as it should, and the pump doesn’t need re-primed afterwards.  Like the old pump, you can tell when you’re starting to hit the bottom of the tank.  It’s a different behavior though.  I’d normally notice the pipe-rattling frequency change with the old pump, now it starts ingesting air and spitting.  You know you’re about to be out of water, with enough time to do something about it.

10 Cold Weather RVing Tips for Water Management

It’s beginning to look a lot like Christmas….aaahhhh! Not so fast, but days are getting shorting and cold weather is approaching.  This marks the start of a series of cold weather RVing tips, in the form of a “top 10” list based on my 11 winters in an RV–including temperatures approaching -30°F, and seeing just what it’s like to break an 1891 record for the number of days without getting above freezing.  Here’s the list:

Continue reading 10 Cold Weather RVing Tips for Water Management

Recipes and Links from Cooking Seminar at the National HDT Rally

For the third time, I’ve stumbled my way through a 2-hour cooking seminar without knowing how to cook.   The 2017 National HDT Rally was the biggest yet, and the cooking seminar was no exception.

In part because of the size of the crowd, the location was moved–there was a lot more seating, but no permanent kitchen.  That introduces a few new challenges, but also keeps the focus on keeping the cooking pretty simple.  Having cooked a number of meats and appetizers in past years, I decided double-down on healthy stuff, and include a couple of desserts (one healthy, one not so much).  The two main dishes are both well-balanced and high in protein.

I have also included some links to some of the tools used in the seminar–sous vide, cooktop, utensils, cookbook, etc.  The links are to Amazon listings, but as always, shop around for the best prices.

Chicken Lasagna

This recipe is a twist on an old classic, made a little bit healthier by using whole-wheat pasta, chicken instead of beef or sausage, cream cheese, and unsweetened marinara sauce. Tweaked a little to cook in a crock pot, which takes a little longer but can be more convenient in an RV.

  • Uncooked whole-wheat pasta (can be lasagna, ziti, etc.)
  • 4 cups shredded cooked chicken (can use canned chicken)
  • 1 1/2 teaspoons dried basil
  • 12 ounces cream cheese, softened
  • 1/2 cup chicken or vegetable broth
  • 3 cups marinara sauce (no sugar added or low-sugar)
  • 4 cups shredded mozzarella cheese
  • 3/4 cup grated Parmesan cheese

Combine chicken, basil, 8 ounces of cream cheese, and 1/4 cup broth. Spread about 1/3 cup marinara on the bottom of crock pot, followed by a later of pasta, more sauce, and the chicken mixture.  Add 3/4 cup mozzarella, and sprinkle 2 tablespoons of Parmesan. Repeat for 4 layers.  Mix the remaining cream cheese and broth and spread over the top, followed by the remaining cheese.

Cover and simmer in crock pot for 3 hours or so.

Link to original recipe: https://www.prevention.com/recipes/quick-creamy-chicken-lasagna

Turkey Chili

This recipe is pretty similar to the way I found it, though I use 2 pounds of ground turkey (mostly because it’s usually sold in 1lb packages), and we add a small can (4 oz) of jalapeno peppers.

  • 1 large onion, chopped
  • 1 large orange, red, or yellow bell pepper, chopped
  • 1 clove garlic, minced
  • 2 pounds lean ground turkey breast
  • 1 can (28 ounces) diced tomatoes
  • 1 can (15 ounces) no-salt-added tomato sauce
  • 1 can (15 ounces) red kidney beans, rinsed and drained
  • 1 can (15 ounces) pinto beans, rinsed and drained
  • 2 tablespoons chili powder to taste
  • 1 teaspoon ground cumin
  • 1/4 teaspoon red pepper flakes
  • 1/2 cup reduced-fat sour cream
  • 1/2 cup shredded reduced-fat Cheddar cheese
  • 1 small can jalapeno peppers
  • Crackers

Cook turkey in deep pan over medium heat.  Add remaining ingredients, and simmer for at least an hour.  Serve in a bowl with a tablespoon or so of sour cream, topped with shredded cheese and crushed crackers.

Link to original recipe: https://www.prevention.com/recipes/mens-health-one-pot-turkey-chili

Peanut Butter Balls

  • 3/4 cup peanut butter
  • 1/4 cup honey
  • 1 scoop chocolate or vanilla protein powder
  • 1/2 cup raw oats

Mix ingredients in bowl, form balls about 3/4″ in diameter on wax paper.  Put in freezer for 30 minutes or longer.

Optional: Melt dark chocolate chips in microwave-safe dish. Insert a toothpick in each ball, and dip into melted chocolate.

Corn, Carrots, Tomatoes, and Pasteurized Chocolate Chip Cookie Dough

These recipes were all prepared straight from the Modernist Cooking Make Easy: Sous Vide book.

Joseph Joseph Nesting Utensils

I think I’ve talked about these before, but since a few people asked after the seminar, here’s a link:

Note that as I write this, the “blue” set is only $11, where the multicolor set I have is more than double that.  The stand for mine is anchored to a corner of the kitchen counter with a piece of 3M Command adhesive/velcro.

Copper Pans

I’ll admit I was wrong here.  I got this pan as a gift, and being an as-seen-on-TV deal, I was pretty skeptical of the quality and functionality that this thing promised.  After giving it a chance, however, it’s easily my most-used piece of cookware.  There’s not a single blemish on the cooking surface, nothing sticks, and it regularly goes through the dishwasher.  It’s also compatible with the induction cooktop, and oven safe (though the long handle makes that less-than-practical for most RV ovens).

Induction Cooktop

In the seminar, I used a two-burner portable induction cooktop.  They’re a little more expensive than two single-burner induction cooktops, but it’s advantageous for plugging into a single circuit, as it automatically manages the power draw of the two burners to prevent tripping a circuit breaker.  As you increase the power of one burner, the other drops if needed.

If you’re not familiar with induction cooktops, the big advantages are a quick response similar to cooking with gas, and a cooking surface that isn’t heated–so spills are much easier to clean.  Induction cooking directly heats the cookware on top, and makes more efficient use of energy.  It does require, however, that the cookware is ferromagnetic.  Look for an induction-ready marking, or test the pan bottom with a magnet before purchase.

Sous Vide Immersion Circulator

In the seminar, I used a Sansaire cooker, which has been on the market for some time.  It benefits from simplicity and an 1100W heating element, but lacks some of the advanced features of newer models that are often available at a lower price.  You can get them very inexpensively refurbished, but the $183.49 price tag new is a bit much.

Here are a few others that are good buys:

 

5-minute modification: Replacing 12V Power Outlet with USB Ports

Every once in a while, you have a nagging project that you put off because it’s easy.  This is one of those.  I’d had a problem with the mount for the factory 12V power outlet on the dashboard of the Grey Ghost–the mounting tabs had worn to where it didn’t stay put.  Since there’s a second 12V outlet right next to it, and this one always had a USB charger in it, I decided to make that more permanent and fix the sloppiness at the same time.

The replacement part was this round power port with 2 2.1A USB ports.  It’s just slightly larger than the power port it replaced, and with a locking nut from behind, won’t have the same problem with falling out:

To install it, I used a sanding drum on my Dremel tool to just slightly enlarge the opening, put the power port through and locked it in place. For the wiring, I simply took the two female spade conectors out of the factory plug and fit them over the male spade terminals on the power port–they were conveniently the same size.  So no cutting or splicing, and now there’s one less thing flopping around in the cab.

Garbage Disposal Macerator Update

As I close in on 2 years using this macerator setup, built around a garbage disposal and first outlined back here, I can say I’m still pretty happy with it.  I recently even pulled it out at a dump station, when the RV at the station decided to have lunch, clean house, and walk the dog or something–after waiting a while, I simply dragged my hose up to the sewer connection, and pumped right on by them.

The main reason for this quick update though is that I happened to notice one of the best-rated garbage disposals show up in a list of sales items.  Just for the day, it’s only $41.24 (with Prime delivery too).  With 4.4/5 stars on over 1,000 reviews, it’s pretty popular.

Make the Water Pump Run Less Frequently

More than likely, you’re used to the water pump cycling on as soon as you turn on a faucet.  Even if you just need enough to swallow a pill, or that tablespoon for your cookie mix, you’re worried about waking up the poor soul whose pillow is right above the water pump.

It doesn’t have to be that way.  With the addition of a small accumulator tank, you can run as much as a couple of gallons of water without the pump needing to run.  When it does run, it’ll cycle on and run long enough to rebuild that same volume.  It’ll also go a step further than last time in reducing the amount of noise the pump makes, as it will absorb some of the pulsating inherent with a diaphragm pump.

Here’s what you’ll need:

  • Accumulator tank.  The 1 or 2-gallon size is probably what you’ll be looking at in most RVs.
  • 1/2″ x 1/2″ x 3/8″ Add-A-Tee fitting
  • 1/2″ FIP x 3/8″ compression flexible hose
  • 3/4″ FIP to 1/2″ MIP adapter and pipe thread sealant

Like last time, once you see the parts list, it’s pretty straightforward.

  1. Turn off the water supply, drain the lines as before.
  2. Install the Add-A-Tee on the water pump outlet, between the hose added last time and the pump.
  3. Connect the new flexible line to the 3/8″ outlet on the tee.
  4. Attach the adapter to the accumulator using pipe thread sealant
  5. Connect the other end of the new flexible line to the accumulator.
  6. Check for leaks, and mount accumulator in place.

Making Your Water Pump Quieter with Flexible Hoses

This is perhaps the simplest of the modifications, and perhaps the best bang for the buck.  This simply involves replacing the rigid pipe connections to your water pump with flexible hoses, so that the pump’s vibrations don’t rattle your pipes as much.

Here’s what you need:

  • 2 hoses with 1/2″ NPT ends.
  • 2 1/2″ NPT hex nipples
  • Pipe clamps to secure rigid pipe
  • Open-ended wrenches to fit the hose ends and nipples.

At this point, it should be pretty self-explanatory, but here goes:

  1. Turn off the pump, and the city water supply.  Close off the freshwater tank, or if there’s no valve, empty it. (If there’s no valve, add one while you have things apart.)  Open a faucet, toilet, and/or low-point drain to minimize spilled water.
  2. Prepare for a little bit of spilled water.  A couple of towels and/or shallow pan should work.
  3. Disconnect female pipe fittings from both sides of pump.  Leave the pump strainer in place.  You shouldn’t need any tools to do this, though a wrench can help.
  4. Install one hex nipple on each of the flexible hoses, using wrenches to make sure you have a snug fit.  The hoses seal with an O-ring, so you don’t need any pipe thread sealant, and don’t need to get carried away tightening.
  5. Hand-tighten one of the flexible hoses onto each side of pump.
  6. Connect the original pipe fittings to the ends of the hoses with the nipples.
  7. Tighten everything up, and with the valve still open from step 1, turn on the pump.  Make sure the tank valve is open and there’s water in the tank.  If there are no leaks at this point, close the faucet/drain valve, and let pressure build while watching for leaks.
  8. If everything checks out, secure the rigid pipe so that it doesn’t contact the pump or rattle against anything around it.

 

Making your Water Pump Work Better

Every time I visit someone else’s RV and hear the water pump kick on right when a faucet opens, the rattling of pipes, and the pulsating trickle of water from the faucet, I can’t help but think about how much better I have it in my rig.  Given that I’ve never seen a few of the things I use in other rigs, I thought I’d explain what they are and how to put them to use in the next few posts.  Here’s the list…

Continue reading Making your Water Pump Work Better