Re-plumbing the Fresh Water System on our Catalina 34 Mk 1
Stuck at home, keeping a Social Distance from friends, neighbors and our boat, I have plenty of time on my hands. What to do? Plan projects of course!
We've had our share of plumbing failures over the past 5 years and each time I have repaired the part that failed, or updated the part that needed it. But the issues of having reinforced poly pipes that expand when pressurized linger on. So, it's time to re-plumb the entire system.
We've had our share of plumbing failures over the past 5 years and each time I have repaired the part that failed, or updated the part that needed it. But the issues of having reinforced poly pipes that expand when pressurized linger on. So, it's time to re-plumb the entire system.
 |
| Tank Selector |
Here's an example of 'why' do this. This is the Tank Selector which I made just over a year ago. It shows 4 hose clamps, which looks a whole lot neater than the disparate valves and connections we had previously.
All of the other hoses in the system have double hose clamps, There are more than 100 hose clamps on the Fresh Water hoses that supply the galley and the head/shower. Each one is a point of potential failure.
The various fittings in the system require multiple adapters to convert from the fitting to the reinforced hose. So there are multiple fittings that can be eliminated by using simpler adapters. eg. 3/8" Faucet connecting to 1/2" piping.
The various fittings in the system require multiple adapters to convert from the fitting to the reinforced hose. So there are multiple fittings that can be eliminated by using simpler adapters. eg. 3/8" Faucet connecting to 1/2" piping.
Using PEX and PEX crimps, will dramatically cut down the number of connections, eliminate hose clamps and reduce the number of additional adapters.
The good news is that the Faucets, Shower head and Water Filters are all new items replaced or installed in the last 4 years.
I will not be replacing the Fresh Water tanks - that's a whole different game - involves too much dismantling.
The Plan.
After much research, I have decided upon PEX piping and crimp fittings. Here's a diagram of the water system and the pipes which are color coded: Red = Hot Water, Blue=Pressurized Cold Water and Black/White = Un-Pressurized cold water, Amber = Temperature Controlled water.
I'll use Pex Elbows to ease the routing of the Pex Tubing. eg. The tubes that connect the Aft Tank to the Ball Valves is not a straight line, so it will likely require two or three Elbow fittings rather than try to bend the pipe in a tight radius.
Note: I asked C34 owners which was the best size for the piping, general consensus seems I could use 3/8" tubing. But as the tank connections appear to be 1/2" and the pipe runs have to include several elbows in order to avoid hard turns in the pipe radii, I'm going to use 1/2" pipe and fittings. Water pressure at the faucets and shower are not really an issue. The current piping and the number of connectors/adapters does not reduce the water flow significantly, and I wouldn't be opposed to a reduction in water pressure - saves water usage.
Tools:
 |
| PEX Clamp Crimp Tool Kit |
Some of the fittings will require a wrench, but this is the tool I'll use to make the crimp connections.
It's not the easiest tool to use in tight spaces, and this is a boat! That's everywhere. I have used it in my garage. Plan is to make as many of the crimp connections before running the pipes. It doesn't require gorilla strength.
Nice tool! The crimper does both crimping and crimp removal.
I guess I'll have to keep it on-board with a bunch of spare crimps, you know, just in case 😏
The PEX pipe cutter is just a bonus.
Amazon
Tool Cost: $34 at Amazon.
Materials
 |
| PEX Clamp Crimps |
It's 304SS but I'm pretty sure all of the existing Hose Clamps are also 304SS.
SharkBite 25-Pack 1/2-in dia Stainless Steel PEX Pinch Clamp Crimp Fitting
Lowes:
Cost: $10.58 for 25
SharkBite 25-Pack 3/4-in dia Stainless Steel PEX Pinch Clamp Crimp Fitting
Lowes: (These came with the PEX crimping tool) I only need 2 + Spares.
Cost: $6.98 (Pack of 10)
The PEX Tubing is available at my local LOWES store in 20' lengths and 10' lengths.
Probably have some left over, but I'll take the same route: buy more than I need and return what I don't.
Lowes:
Cost $6.98 for 20'
Cost $8.00 for 25'
5' Length of 3/4" White
Cost: $3.26
1/2" PEX Barb X 1/2" MNTP Pipe fittings that I believe should fit the Water Tank Outlets, 3 Way Valve and the Filter housings
Lowes:(LINK)
These are the 1/2" PEX Barb X 1/2" FNPT Elbow Pipe fittings that I believe should fit the Water Pump and the Thermostat in the Shower line.
Lowes:(LINK)
Cost: $10.97 (5 Pack) (need 2 packs)
I spent hours searching for a 3/8" MNPT to 1/2" PEX Barb adapter Elbow. I had given up and decided to get the Brass 3/8" MNPT to 1/2" FNPT Adapter and then use a 1/2" MNPT to 1/2" PEX Barb adapter.
Gave it one last shot and found the 3/8" MNPT to 1/2" PEX Barb Elbow on ACEHardware.com
Ace Hardware:(Link)
Cost: $5.59 (5 Pack)
I could not find a 3/8" MNPT to 1/2" PEX Barb for the Faucets pipe connections to the PEX tubing, so I had to get these 3/8" MNPT to 1/2" FNPT Adapters to connect to 1/2" MNPT to 1/2" PEX Barb.
Fastenal:(Link)
Cost: $15.25 (5 Pack)
I looked all over (the Internet) but could not find a PEX Barbed 3 way valve. But I did find this item.
It's has FNTP Connections. That's 'Female Nataional Threaded Pipe. So I believe that the 1/2" Pex Barb to 1/2" Pipe Fitting will create the transition to the PEX piping. I'll most likely use Straight for the output and elbows for the inputs.
The handle can be removed to facilitate panel mount, so I only need to drill a hole about 1/2" dia in the face of the galley side and two small screw holes to secure it to the panel. Max panel thickness is 0.17".
US Plastics Corp (Link)
Cost: $20.66
Shipping: $15.00
Cost Total: $35.66
Another item I could not find: 1/2" PEX Barb x 1/2" FNPT Elbow. So I'll have to use Straight connectors and add an Elbow to the piping.
Lowes(Link)
Cost: $7.99 (5 Pack)
Rather than make a manifold by connecting T fittings, I found this 4 port manifold online.
SharkBite 25-Pack 3/4-in dia Stainless Steel PEX Pinch Clamp Crimp Fitting
Lowes: (These came with the PEX crimping tool) I only need 2 + Spares.
Cost: $6.98 (Pack of 10)
 |
| PEX Piping |
The PEX Tubing is available at my local LOWES store in 20' lengths and 10' lengths.
Probably have some left over, but I'll take the same route: buy more than I need and return what I don't.
Lowes:
Cost $6.98 for 20'
Cost $8.00 for 25'
5' Length of 3/4" White
Cost: $3.26
1/2" PEX Barb X 1/2" MNTP Pipe fittings that I believe should fit the Water Tank Outlets, 3 Way Valve and the Filter housings
Lowes:(LINK)
Cost: $5.72 (5 Pack)
Lowes:(LINK)
Cost: $10.97 (5 Pack) (need 2 packs)
I spent hours searching for a 3/8" MNPT to 1/2" PEX Barb adapter Elbow. I had given up and decided to get the Brass 3/8" MNPT to 1/2" FNPT Adapter and then use a 1/2" MNPT to 1/2" PEX Barb adapter.
Gave it one last shot and found the 3/8" MNPT to 1/2" PEX Barb Elbow on ACEHardware.com
Ace Hardware:(Link)
Cost: $5.59 (5 Pack)
Fastenal:(Link)
 |
| 3 Way Ball Valve FNPT connections |
I looked all over (the Internet) but could not find a PEX Barbed 3 way valve. But I did find this item.
It's has FNTP Connections. That's 'Female Nataional Threaded Pipe. So I believe that the 1/2" Pex Barb to 1/2" Pipe Fitting will create the transition to the PEX piping. I'll most likely use Straight for the output and elbows for the inputs.
The handle can be removed to facilitate panel mount, so I only need to drill a hole about 1/2" dia in the face of the galley side and two small screw holes to secure it to the panel. Max panel thickness is 0.17".
US Plastics Corp (Link)
Cost: $20.66
Shipping: $15.00
Cost Total: $35.66
Another item I could not find: 1/2" PEX Barb x 1/2" FNPT Elbow. So I'll have to use Straight connectors and add an Elbow to the piping.
Lowes(Link)
Cost: $7.99 (5 Pack)
 |
| PEX 1/2" Barb 4 Port to PEX 3/4" Barb Manifold |
Rather than make a manifold by connecting T fittings, I found this 4 port manifold online.
4 Port 1/2" PEX Barb Manifold with 3/4" PEX Barb input connection.
It will require a 3/4" PEX Barb to 1/2" PEX Barb coupling to connect the input to 1/2" PEX piping.
Home Depot: (Link)
Cost: $12.98ea.
 |
| PEX 1/2" Barb to 1/2" NPT Adapter |
Pex 1/2" Barb to 1/2" NPT Pipe adapter.
I'll need one of these to connect to the Output port of the 3 Way Ball valve. The rest of them will most likely be used for the faucet connections.
Lowes:(Link)
Cost: $4.67 (pack of 5)
 |
| PEX 1/2" Barb to PEX 3/4" Barb Adapter |
I'll have to get a very short length of 3/4" Pex piping to connect to the Manifold.
ACE Hardware:(Link)
Cost: $3.95
As per the diagram above, I need 3 of these 1/2" PEX Barb 'T's
ACE Hardware: (Link)
Cost: $3.59 (5 Pack)
 |
| PEX 3/4" Piping |
The shortest length I can get is 5'
Lowes:(Link)
Cost: $3.26
This 1/2" Push to Connect Check Valve will replace the existing check valve that is connected between the Hot Water Tank Inlet and the Cold Water Supply.
It prevents hot water back flowing from the hot water tank into the cold water filters and faucets.
I could not find a PEX Barbed Check valve.
Lowes (Link)
Cost: $15.98 each.
 |
| Pex 1/2" Barb to Pex 1/2" Barb Elbow |
These 1/2" Pex Barb X 1/2" Pex Barb Elbows will be used to assist in running the piping around the corners rather than try to bend the piping.
Lowes:(Link)
Cost: $2.91 for pack of 5
The Reconstruction:
 |
| Galley Cabinets |
To relocate them, I will have to drill a couple of holes in the galley cabinet side in such a location that they won't be shin catchers. The big plus of having them on the outside of the cabinet is that it's obvious which tank is selected or if they are turned off.
I'm pretty sure it will fit just inboard of the lower drawer front and beneath the cutlery draw
I'm pretty sure it will fit just inboard of the lower drawer front and beneath the cutlery draw
 |
| Three Way Control Valve |
This valve has a handle that cab be removed and replaced in any of 4 positions.
Using this, I can add Nice labels to show where the handle should be to select:- Aft Tank -- Off -- Mid Tank.
It looks much nicer than the bent metal handles that are on most of the valves that I found.
That pretty much describes the Why, What, With and How.
I estimate the total cost to be as shown in the Sheet below:-
The (Demolition) Process:
- Drain the tanks: And while draining them we will flush them in the hope of removing much of the crud that has accumulated in the past 32 years. Basically we'll use a pressure hose inside the tanks.
- Disconnect the Mid-ships water tank (easy)
- Disconnect the Galley Faucets
- Disconnect the Head Faucet, Shower control valve and Thermostat fittings.
- Disconnect the Hot Water Tank and the 3 Water Filters.
- Except for the Aft tank water hose, remove all of the old water hoses and run messenger lines where needed. (some are just a few inches long)
The Aft tank hose to the ball valve is the longest single hose. It runs from the forward lower edge of the Aft tank and runs below the Aft Cabin, under the Galley floor and into the Galley cabinet locker. I'm hoping I can remove and replace this hose in one step rather than go dumpster diving multiple times. With luck I'll be able to use the old hose as the messenger for the new.
So, that's the plan. Time to order the parts!
Stay Safe!
