… New Water System — Fostering Adventure

Upgrading the fresh water system

Two Pumps Are Better Than One

You can see here the shut off valve on the right side of the water pump. Unfortunately, the water from the tank enters the pump on the left side, and there is no valve between the water tank and the pump. Brilliant, absolutely brilliant!

When we received our expedition truck from the builder, we were expecting the vital systems of the truck to be duplicated for failure redundancy. After all, that’s what makes the difference between a regular RV and an expedition vehicle. One system that wasn’t was the pressurized fresh water supply. Since the pumps that are used for fresh water delivery eventually fail, it’s important that they be duplicated. Or at the very least, they should be easily changed so a spare pump could be carried for remote location replacement. Thanks to the builder, we had neither duplicate pumps nor the ability to change the pump out in the field. The main problem is that the plumbing braintrust at the builder installed the water tank shut off valve on the wrong side of the pump. So to change a failed pump, we’d have no choice but to drain the water tank in order to do so. Not something you’d want to do if you’re traveling in an arid region of the planet where replacement water is scarce.

Once Again We have To Re-do Inadequate Work

In the course re-working things on the truck, we always find things done by the builder that astound us. It’s inevitable, as proven time after time over the six year history of this vehicle.

The garden hose female thread is on the left and the garden hose male thread is on the top right. Compared to the 3/4” male pipe thread on the bottom right, they’re roughly the same diameter, but a completely different number of threads per inch.

As always, the builder never fails to disappoint. This time it’s with fittings used to connect certain parts of the water system together. In a number of places flexible hoses like the ones seen on the back of laundry machines are used to connect one section of the system to another. Specifically, these hoses are used to connect the water storage tanks and system plumbing to the patch bay located on the outside of the truck. This is where we hook up shore services like water and electricity to a control panel. This panel has to be removable, so flexible lines are used so the panel can be unscrewed and pulled out enough to disconnect the hoses. These hoses are where the problem lies. They have a very specific attachment on each end that screws onto a mated fitting, and that junction is nothing more than a standard garden hose connection. Yes, it’s just a garden hose end, but it has a very specific threaded collar that is unique to a garden hose. It won’t fit anything else. So what does the builder’s plumber do, he of course forces the garden hose collar onto a 3/4” tapered male pipe thread and tries to make it seal. It’s like trying to mate an elephant with a chihuahua. They both have four legs, two ears and a tail, but the coupling probably won’t be successful.

The patch bay with the flexible hoses from the water tank, and city water circuit hanging out along with the shore power wiring connectors.

The back of the control panel with all new plumbing components and proper garden hose connections for the flex hoses.

We all know that a garden hose can be hand tightened on the spigot, and it seals just fine. But for this brainless idiot to try and get the two mismatched fittings to thread together he had to have used wrenches, and forced the issue to such a degree that they were almost impossible to get apart. It was amazing that, with the differences in the threads, he was able to thread them together enough to get most of them to even seal. I say most of them, because there was one that didn’t. I could tell just by handling the connection and feeling the slop in the joint. The hose turned easily in the threaded collar, which meant the rubber washer inside was not seated tightly between the two halves of the joint. Fortunately for us, and it really was fortunate, this one unsealed joint was the connection that we would’ve used to hook up to shore water in an RV park or such if we didn’t want to use the onboard pump to pressurize our domestic water system. What's fortunate is that in all the years we’ve owned this vehicle, we’ve not yet hooked onto a shore supply. Sure, we’ve filled our water tank dozens of times, but that uses a different circuit which, as luck would have it, was sealed. Had we indeed hooked onto a city water supply and turned on the tap, the entire rear of the truck would have been flooded.

Planning the Upgrade

The first thing we have to do in any upgrade is to determine if it’s possible. We have to fit in more equipment than previously existed, so some work with photos and the computer was necessary. By scaling images of the components and placing them on a photo of the area in question, we can determine how the layout can be done. After that it’s a matter of trying to route the hoses so they not only connect the components, but also look good or, dare I say, impressive.

The area we want to work with as it came from the builder.

This is how I envisioned it when looking at the area in the truck.

My finished placement and hose routing design.

New Equipment

One of two 12 volt water pumps we'll be using.

The accumulator tank stores a small amount of water with its own pressure source.

You can see the difference in the size of the new pump head on the left compared to the old pump on the right.

Since we are doing a complete replacement of the water pressurizing system, we elected to change the brand of pump we’ll have to something a bit better than the obsolete Flojet pump that the builder installed, and is no longer available. Moving to a marine brand instead of an RV one, we decided on the Jabsco Par-Max HD. It’s a 5 gallon per minute pump with a 40psi pressure output, and it’s a newly redesigned pump series. So it should be around for a few years before it goes obsolete. The beauty of these pumps is that they are heavy duty in comparison to a regular RV pump, and should provide us with years of problem free service.

We also elected to install a small accumulator tank, also a Jabsco product, to help with vibration mitigation as well as reducing cycling of the pump. The accumulator holds a small reservoir of water and can feed it into the water flow without immediately causing the pump to run. This is particularly beneficial in the middle of the night if you want a small amount of water, and don’t want a running water pump to wake up your sleeping partner. We would have preferred the larger version of this tank, but we just didn’t have the room on our plumbing wall, and didn’t want to try and fit it in somewhere else. It would just complicate the already bothersome job.

Mounting the Water Pumps

The new pumps are not that much bigger than the old pump, but they are considerably heavier. Hopefully this speaks to their heavy duty nature.

The pumps are quite heavy and only have four mounting screws, so instead of mounting the water pumps directly to the plumbing wall, which is made from laminated layers of 5/16” plywood and foam insulation, we decided to mount them to a piece of 1/4” Delrin. It’s stronger than the thin plywood, and can be easily machined to receive proper machine screws. The Delrin can then be permanently screwed to the plywood with enough wood screws to distribute the weight properly. Using the machine screws for the pumps will also make it easier for swapping them out later if necessary. We could have used knife edge threaded brass inserts for the 5/16” thick layer of plywood, but several of the ones the builder put into the wall have already pulled out. Plus, we couldn’t find anywhere to buy only a few of them at a time, so would have had to buy a box of 100 at a rather steep price. The 1/4” Delrin was a crop from a previous job, so technically, free.

The 1/4" Delrin was kept as small as possible, but still large enough to displace the pump weight over a decent area.

Holes were laid out for pump screws as well as the screws that would attach the Delrin to the wall.

Pump holes were threaded, and the holes for the wall screws were countersunk.

Enough room had to be left between the pumps so the strainer and exit fitting could be unplugged from the pump when service was needed.

Room was also calculated for the electrical junction box that needed to go between them.

The screws were just a little too long, but cutting them wasn't desirable. The rolled thread end on the screws is less damaging to the Delrin.

Spacers were needed to offset the screw length.

The spacers were glued to the baseplate using a urethane glue.

These pumps were different than the original in that they had rubber isolation feet included to reduce vibration transfer to the cabin.

This shows the finished pump mounting with the installed electric junction box.

To control which pump would operate, we needed a switch. Since we had a number of Contura switches left over from our Land Rover Defender 90 build, and one was an On-Off-On configuration, it was perfect for this scenario. All we needed to do was get a decent looking junction box and blank lid, and we could modify it for our need.

A rectangular cutout had to be made in the steel cover plate for the switch. So a Dremil tool was used to do that.

The switch was positioned offset to accommodate the label.

The box is just deep enough to allow connections to the back of the switch.

The switch is located under the hot water tank where it will be protected from accidental activation.

Removing the old system

We had to start by removing the builder’s original work. The water pump was easy, once we had completely drained our water tank of course. Remember they put the shut of valve on the wrong side of the pump.

After the pump we had to remove the control panel from inside the patch bay so we could get to the end of the water tanks where the connections originated. Then we had to figure out their hose routing and start unthreading and cutting away the lines we wanted to replace.

The control panel is held on with six screws, but it's not exactly convenient to get out. It conflicts with the outer door, so can't be pulled straight out.

Of course, once the panel is wiggled out of the opening all one can do is let it hang by its connections. Not a very good design at all.

All of the connections on the back of the panel are hard plumbed, so can't be easily disconnected. We'll be changing that.

This is the old pump we are removing. Notice the shut off valve is downstream of the pump, instead of between the pump and the tank.

As you can see, once the pump is removed there is no way to install a valve. So it all has to be redone.

This shows how the plumber installed the feed line that arcs up from the bottom left. It splits into the hot and cold circuit. But it's the same as the two sub-lines. It should be twice as big.

This is the drain line that goes through the floor and out the bottom of the habitat.

Here I am working at getting the PEX drain line out so it can be replaced with the new soft line.

All the feed lines had to go. So to start we had to wrestle with line that came from the water tank. It was an awkward place to work.

Trying to undo the bonze fittings was very difficult. We had to try and brace things so as not to damage the plastic tank threads.

Once we got the union apart, the downstream work was much easier. But we still had to get the pipe out of the elbow in the tank. Very hard indeed.

Once the pipe was out we could back the elbow out of the tank.

The vertical white pex with the brass fitting is the feed line for the pumps. That will be replaced.

This is the feed line for the outside tap. The tapered pipe thread has to be replaced with a proper garden hose fitting.

This is the infill fitting for the fresh water. It also is a tapered pipe thread that has to be replaced with the garden hose thread.

With the elbow removed we could inspect the threads to see that they were undamaged.

building Something Better

This shows the 3/4” braided vinyl water line with the brass 3/4” hose barb fittings.

We pre-assembled all the brass components on the bench for an easier job. Notice all the barb fittings for the soft hose to connect to.

The plumber that worked on our truck used hard connections, and hard lines everywhere except where the system attached to the patch panel control board. Hard lines can be good in some cases, but bad in others. In a situation where the plumbing and its larger components are going to be bounced around a lot off-road, and there is a chance that something might shift, hard connections and lines can suffer damage and compromise the sealed joints. So for our re-build of the system we elected to use soft lines between the hard connections to eliminate that possibility. We also wanted to increase the volume that the lines could carry, not so much to increase the flow out of faucets and such, but rather to reduce the work the pump has to do in pulling the water from its reservoir before it sends it down the line. This will cause the pump to work less thus extending its life. Our choice of line was 3/4”I.D. flexible braided vinyl water line, which was used with 3/4” barb fittings for the connections. All materials are certified for potable water usage. They’re also available just about anywhere, and installable with common hand tools. The armored PEX that the builder used isn’t.

Before the new soft hoses were connected to the new elbow, we made a bunch of connections to it outside of the truck. It was easier.

Once those connections were crimped to their fittings, it now only took one hose clamp to connect it all to the elbow.

The pump line arcs up from the main feed line and goes through the wall.

The end of the main feed line is also the tank drain line which is controlled by this valve.

When the valve is opened the tank drains out and elbows down through the floor.

The drain line protrudes out through the bottom of the habitat and has a garden hose fitting on it so it can be connected to, and supply a pressure washer.

The red PEX line was removed from the hot water tank outfall.

The hot water tank in-feed valve was replaced with a new one that didn't have a side vent. It's totally superfluous.

Our new distribution manifold mounted in it's new home.

A mounting plinth had to be made to hold the junction crossover T the right distance off the wall.

The crossover T is where the city water line and the pump water line joint the hot and cold circuit. Only one is used at a time.

The plinth also would help support the pump feed lines as they passed over it.

This shows the crossover T and how it connects to the hot circuit on the left and the cold circuit on the right.

The pumps had to come off the mounting panel so it could be screwed to the wall. Then the pumps were remounted on the panel.

Once the second pump is re-mounted, the electrical wiring would have to be reconnected.

The accumulator tank is connected to the pump out-feed line just before it enters the crossover T.

With all the new equipment properly mounted it was just a matter of running the new soft lines.

Routing the lines took time to weave them properly throughout the system.

This shows the cold line connected to the cold distribution manifold.

Pump one is done, now just have to do pump two and the city water circuit.

With the path of all the lines figured out, we needed to make a modification to the main boiler heat line for everything to lay flat against the wall. Made from 3/4” armoured pex tubing, we had to put several bends in it to raise it up about an inch on the wall. Since we didn’t want to breach the boiler system by removing the hydronic tube for bending, I fashioned some bending sticks so I could bend the very stiff tubing in situ. These sticks were used to brace the armored pex in one direction while another stick was used along with a pry bar to force the tube in the direction we wanted. Several placement setups were needed to bend the tube one way, and then the other.

The area is a bit tight for the hoses to lay the way we'd like. So the heavy red line needs to be moved up about an inch.

The red armoured PEX is really stiff and difficult to bend. So we had to support parts of it while bending others.

The PEX had to be bent upward from the water tank, and then back down level. So the sticks had to be moved with each bend.

Two sticks braced the PEX, and one was used with a pry bar to bend it.

Here the red tube is braced against the underside of the pump mount so the horizontal line could be straightened and made level.

This is the horizontal red PEX line before it is bent and raised up the wall.

This is the red PEX line after bending. Notice the upward sloping section on the far left by the hot water tank.

It's only an inch higher, but it gives us the clearance we needed for both soft lines to travel unimpeded to the pumps.

With the hydronic heating line bent out of the way we could now finish running the final water lines which will finish the installation on the plumbing wall.

The city water circuit on the bottom is connected to its shutoff valve.

The city water line is connected to the bottom of the crossover T, which completes its installation.

The final lines to the two pumps are finally connected, and the system on the plumbing line is complete.

This closeup of the pump connections shows the stainless steel crimp rings that were used instead of hose clamps. They're faster and more positive than hose clamps, and look better too.

Wiring for pump operation

With the installation of the pumps and water lines on the plumbing wall complete, all that remained was to run new 12 volt electrical lines for power. Although we would be using the original pump power line, it now had to be split so that it could run two pumps. Since we’d only be running one pump at a time, the current draw would remain the same. We’d just need a switching point to direct the current to one pump or the other.

The pump power wire only stuck out of the wall by two inches. So we had to bore a larger hole so we could grab the wire and pull it through where the junction box would sit.

We had to add extra wire onto the original so we'd have enough to connect to the new switch.

The extensions were soldered on and then sealed with shrink tube.

The junction box and the manifold were mounted deliberately so the valve handles would clear the box when turned.

The original pump power line was first connected to the back of the switch using spade connectors.

We used a marine grade 14ga wire to run to the pumps. A 3 wire line was run. One for each pump and a common ground.

The wire was white like the wall, and flat so it could be fed in behind everything else which held it in place when done.

The three wires from the pumps were then connected to the switch.

All the wire would not fit into the box, but because it was low voltage it could simply be pushed through the back of the box into the void behind the wall.

The connections to the pump wires were done with the new style wire connectors. They're positive, quick and come in different wire multiples.

The flat wire lays flat until a 90º bend in the flat plane needs to be done, but it can lay flat under the tubes right into the junction box.

It's always convenient when there is a threaded insert in the wall right where we wanted to install a wire support clip.

Connecting the system to the patch Bay

At some future point we’ll be redoing this control board as well. The builder did an appalling job at laying it out, and the workmanship is atrocious. Components are out of square and misaligned.

The last step in the installation is to tie the system into the patch bay control panel so we can get water from outside sources into the truck. To do this the water tank needs a connection, as well as the city water circuit that bypasses the pumps. There’s also a feed from the pump circuitry back to the panel to provide pressurized water from the water storage tank to the outside water faucet.

This is where we had to replace the 3/4” tapered pipe thread fittings with the proper garden hose thread fittings. Only by doing this can we be assured of a proper seal with the flexible hoses.

With the control panel removed we were able to clean up the wiring and flexible connection hoses.

This is the feed point for the outside faucet and had to be replaced with the garden hose fitting.

The pipe fitting was crimped to the original PEX which we are leaving. Since we can't remove it, we used a coupling to connect our garden hose fitting to the original tapered pipe thread.

Here we now have the proper garden hose fitting for the flexible lines to connect to.

On the left we have installed the new city water circuit soft hose and garden hose fitting to connect to the control panel flexible hose.

This is the improper flex hose connection for the tank fill that needs replacing.

We removed the old connection and inspected the threads to ensure they are good for the new connection.

This is the new street elbow and garden hose fitting to be installed in the fill location.

Here's the proper installation that should have been done by the builder.

We're basically replacing almost everything on the back of the control board with new, better components.

This shows the soft lines running from the new elbows on the filter pot to the feed points on the bottom of the control board.

We replaced the old filter pot elbows with new stainless ones. They look better on the outside of the board and have a larger bore for water flow.

We also removed the old three-way RV valve and replaced it with a larger bore three-way valve like what we used on the plumbing wall.

When we make a new control board we'll move the components around so the spacing is better.

The builders idea of a good looking layout is severely lacking.

Here's the back of the control board just before we install it back in the truck.

The previous installation was badly done and caused the flexible hoses to kink when moving the panel.

We fashioned some strain reliefs from small pieces of our waterline hoses. They work really well at preventing the kinks from happening again.

We put our new strain reliefs on both ends of all the flexible hoses.

The control panel put back in its position. We need to re-do this board so it looks better. But for now just getting the plumbing properly done with two pumps will do fine.

With all the work finished it was just a matter of re-filling the 180 gallons of water and systematically checking everything for leaks. All of our plumbing joints were water tight, and the increased size of the infill lines sped up the time needed to fill the tanks. But a new infill connection on the outside of the control panel will speed things up even more. This will be done when we redo the panel.

Each pump was run to draw water through the system and out through the sink faucets. Once all the air was pumped out of the lines the sound of the pumps was at least half that of the old pump. The flow from the tap was also much stronger than the previous pump. Both of these were welcome improvements that made all the work worth it. Now that we have a truly redundant system it will make our travels in the remote regions like the Arctic a little less stressful.

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