I am interested in installing a shore water hook-up for my 2001 Hunter 380. Has anyone ever done this before. My marina has extremely high water pressure as well. Would appreciate some tips. Thanks Scott Broad III Short
- Status
- Not open for further replies.
D
Doug T.
Plumbing
Do you just want to keep your tank filled all the time or do you want to use the marina's water (and pressure) directly? Can your boat's plumbing handle the pressure? What kinds of pumps do you have now? You'd have to bypass them all...
Do you just want to keep your tank filled all the time or do you want to use the marina's water (and pressure) directly? Can your boat's plumbing handle the pressure? What kinds of pumps do you have now? You'd have to bypass them all...
P
Peggie Hall/Head Mistress
If the dock water pressure is that high...
The only dock water connection you should even consider is one that refills your tanks. All shore water has higher pressure than boat plumbing can withstand, which is why they all require a pressure reducer valve. However, there are only two kinds of pressure reducer valves--those that have failed, and those that will. When it fails, the pressure WILL blow out your boat's plumbing somewhere, and the volume of water coming in is higher than even 3 BIG bilge pumps can keep up with. Unattended dock water connections have become a leading cause of boats sinking in their slips. The higher the pressure coming in, the more likely the valve is to fail sooner...and refilling your water tank provides a little more protection, especially if you also add a valve that automatically shuts off the water after each 50 or 100 gallons. However, you should never leave your boat--even for an hour--or turn in for the night with dock water on. It's essential that someone be aboard and awake to hear the first sounds of gushing water belowdecks when the pressure valve fails.
The only dock water connection you should even consider is one that refills your tanks. All shore water has higher pressure than boat plumbing can withstand, which is why they all require a pressure reducer valve. However, there are only two kinds of pressure reducer valves--those that have failed, and those that will. When it fails, the pressure WILL blow out your boat's plumbing somewhere, and the volume of water coming in is higher than even 3 BIG bilge pumps can keep up with. Unattended dock water connections have become a leading cause of boats sinking in their slips. The higher the pressure coming in, the more likely the valve is to fail sooner...and refilling your water tank provides a little more protection, especially if you also add a valve that automatically shuts off the water after each 50 or 100 gallons. However, you should never leave your boat--even for an hour--or turn in for the night with dock water on. It's essential that someone be aboard and awake to hear the first sounds of gushing water belowdecks when the pressure valve fails.
T
Tom Boles
I'll take a slightly different view...
I have been thinking of doing this to my own boat (as soon as we close on her, that is!) I agree with Peggy that an un-regulated, un-protected dockside water connection is a great way to sink a boat! However, with the tid-bits below, one can put together a system that works, has reasonable safegards against flooding and provides a good volume of regulated water for your boat at dockside. Nothing will prevent flooding of the boat like a watchfull, aware skipper, however, so I agree that you should never leave the boat with the pressure water connected & "on"! Borrowing a page from the housing industry and one from the RV world, this is what I'd do: 1-use an inlet connection from the RV world that is made from UV resistant plastic. There are several types available, some have built-in pressure regulators (which I would stay away from, because they reduce flow and pressure) 2-As Peggy suggests, us a volume-triggered valve that shuts off after a user-selectable amount. These are found in the gardening section of places like home depot. 3-While at home depot, pick up a brass whole-house pressure regulator. This is a well built, full flow device often used in places that have high or irregular domestic water pressure. 4-While at the RV store, get a one-way valve to put after the pump but before the boat's water system. Surflow (sp) is a common brand. (maker of pumps used in boats & RVs) 5-Tee off after the one way valve and connect up the dockside water inlet. (remember to use a potable water hose for the connection. You may also want to add a small combo (particulate & carbon) filter to the line after the "tee" to keep most of the big stuff and some of the blecky taste out of the system.) I have a similar system in my RV & use it with confidence every time we go camping. Finally, with simple valving, you can use this supply to fill your internal tanks with filtered water without opening a fill on the deck and sticking a random garden hose into the hole and hoping no ugly stuff gets in at the same time! Good Luck!
I have been thinking of doing this to my own boat (as soon as we close on her, that is!) I agree with Peggy that an un-regulated, un-protected dockside water connection is a great way to sink a boat! However, with the tid-bits below, one can put together a system that works, has reasonable safegards against flooding and provides a good volume of regulated water for your boat at dockside. Nothing will prevent flooding of the boat like a watchfull, aware skipper, however, so I agree that you should never leave the boat with the pressure water connected & "on"! Borrowing a page from the housing industry and one from the RV world, this is what I'd do: 1-use an inlet connection from the RV world that is made from UV resistant plastic. There are several types available, some have built-in pressure regulators (which I would stay away from, because they reduce flow and pressure) 2-As Peggy suggests, us a volume-triggered valve that shuts off after a user-selectable amount. These are found in the gardening section of places like home depot. 3-While at home depot, pick up a brass whole-house pressure regulator. This is a well built, full flow device often used in places that have high or irregular domestic water pressure. 4-While at the RV store, get a one-way valve to put after the pump but before the boat's water system. Surflow (sp) is a common brand. (maker of pumps used in boats & RVs) 5-Tee off after the one way valve and connect up the dockside water inlet. (remember to use a potable water hose for the connection. You may also want to add a small combo (particulate & carbon) filter to the line after the "tee" to keep most of the big stuff and some of the blecky taste out of the system.) I have a similar system in my RV & use it with confidence every time we go camping. Finally, with simple valving, you can use this supply to fill your internal tanks with filtered water without opening a fill on the deck and sticking a random garden hose into the hole and hoping no ugly stuff gets in at the same time! Good Luck!
D
Dan
No water hook-up
I would never hook water directly to the boat, even if I were on board. Never know when I might dose off and I don't want to wake up wet. The biggest difference between a boat and RV in the present discussion, is that the boat can sink. A water line failure in the RV will be a minor inconvenience as the water drains towards the nearest exit. Even with a 50-100 gallon shut-off, that will put the water over the floor boards in most boats. We have a new 356 and there was a leak in the water tank fitting that was filling the bilge in just a few days. Had we not checked on it regularly, we could have had some damage. Just my opinion. We fill the tank as needed. Dan Jonas (S/V Feije II)
I would never hook water directly to the boat, even if I were on board. Never know when I might dose off and I don't want to wake up wet. The biggest difference between a boat and RV in the present discussion, is that the boat can sink. A water line failure in the RV will be a minor inconvenience as the water drains towards the nearest exit. Even with a 50-100 gallon shut-off, that will put the water over the floor boards in most boats. We have a new 356 and there was a leak in the water tank fitting that was filling the bilge in just a few days. Had we not checked on it regularly, we could have had some damage. Just my opinion. We fill the tank as needed. Dan Jonas (S/V Feije II)
T
Tony
Showers
I have a water hookup on my 340 i have it for the visits to another marina where there are 1-2 showers for visitors and a line 5 people long. otherwise i use the tank. it is on.. i shower .. it is off. used it to wash out cockpit and made mistake of turning water off at cockpit showerhead blew it right off and that is WITH press. valve in line NEVER ON when i am not right there AND awake Disconnect hose from fitting before i leave boat always possible some numbskull turns on your valve by mistake and leaves on. Of course if the water at your slip is shallow, you won't sink too far. he he
I have a water hookup on my 340 i have it for the visits to another marina where there are 1-2 showers for visitors and a line 5 people long. otherwise i use the tank. it is on.. i shower .. it is off. used it to wash out cockpit and made mistake of turning water off at cockpit showerhead blew it right off and that is WITH press. valve in line NEVER ON when i am not right there AND awake Disconnect hose from fitting before i leave boat always possible some numbskull turns on your valve by mistake and leaves on. Of course if the water at your slip is shallow, you won't sink too far. he he
B
Bob Howie
Tom's On Point
I have installed "city water" in a number of boats over the years and the trick is quality installation and quality parts. Yes, you might have to replace some plumbing lines and there are any number of quality materials than can be used for this and help insure safety. No boat should be left unattended with "city water" hooked up. The precautions are simple; if you leave your boat to go to dinner or a movie, simply don't forget to turn the spigot off dockside and disconnect the hose when you leave to go home. Tom's point on whole-house pressure regulators and solenoids that turn water off after a variable amount has passed through the lines along with the filtration system are also good ideas. The all-brass, user-adjustable pressure regulators are excellent and reliable. The RV industry has had more than 40 years' success with systems installed in their units and there's no reason not to adopt these practices to boats. The key ingredient in all things is to use common sense in your installations and to think about safety and security during the planning stages. It really gripes me when people say adding city water to a boat is tantamount to courting sure and certain disaster. But, I figure those are the same people who will tell you that propane systems on boats are certain to explode at any minute. Tom's advice is sound, forthright and accurate and I believe, from experience, that if you follow his suggestions, you'll not have any problems. Good luck.
I have installed "city water" in a number of boats over the years and the trick is quality installation and quality parts. Yes, you might have to replace some plumbing lines and there are any number of quality materials than can be used for this and help insure safety. No boat should be left unattended with "city water" hooked up. The precautions are simple; if you leave your boat to go to dinner or a movie, simply don't forget to turn the spigot off dockside and disconnect the hose when you leave to go home. Tom's point on whole-house pressure regulators and solenoids that turn water off after a variable amount has passed through the lines along with the filtration system are also good ideas. The all-brass, user-adjustable pressure regulators are excellent and reliable. The RV industry has had more than 40 years' success with systems installed in their units and there's no reason not to adopt these practices to boats. The key ingredient in all things is to use common sense in your installations and to think about safety and security during the planning stages. It really gripes me when people say adding city water to a boat is tantamount to courting sure and certain disaster. But, I figure those are the same people who will tell you that propane systems on boats are certain to explode at any minute. Tom's advice is sound, forthright and accurate and I believe, from experience, that if you follow his suggestions, you'll not have any problems. Good luck.
P
Peggie Hall/Head Mistress
No one is saying shore water is sure and certain
disaster. However, it cannot be over-emphasized that they are NOT like shore power connections that can just be connected and forgotten as long as the boat is at the dock. Like propane and gas engines, they require attention and strict adherence to safety precautions...that when followed, make all of the above completely safe. However, there are people who shouldn't have ANY of the above on their boats...in fact, prob'ly shouldn't even own a boat at all. For them, a shore water connection would be "sure and certain disaster." But for the rest, it's a very nice convenience that just requires paying attention.
disaster. However, it cannot be over-emphasized that they are NOT like shore power connections that can just be connected and forgotten as long as the boat is at the dock. Like propane and gas engines, they require attention and strict adherence to safety precautions...that when followed, make all of the above completely safe. However, there are people who shouldn't have ANY of the above on their boats...in fact, prob'ly shouldn't even own a boat at all. For them, a shore water connection would be "sure and certain disaster." But for the rest, it's a very nice convenience that just requires paying attention.
B
Bob Howie
Other points well taken, too
Peggy's second series of points are, indeed, well taken and she is correct in saying some people shouldn't even be allowed near water, much less permitted to own boats! Or cars...or planes...or an electric can opener. In any endeavor in which lives are entrusted to mechanical contrivances, pro-active pre-emptive maintenance and monitoring should always be the rule regardless of how bulletproof those systems are alleged to be. The same is true with any system on a boat which, by its very nature, lives in an extremely harsh environment. Common sense and an awareness of how things can go wrong protect us all and anytime something does go wrong and provokes disaster, it's not a matter of who was right or wrong, but a matter that can adversely reflect on us all.
Peggy's second series of points are, indeed, well taken and she is correct in saying some people shouldn't even be allowed near water, much less permitted to own boats! Or cars...or planes...or an electric can opener. In any endeavor in which lives are entrusted to mechanical contrivances, pro-active pre-emptive maintenance and monitoring should always be the rule regardless of how bulletproof those systems are alleged to be. The same is true with any system on a boat which, by its very nature, lives in an extremely harsh environment. Common sense and an awareness of how things can go wrong protect us all and anytime something does go wrong and provokes disaster, it's not a matter of who was right or wrong, but a matter that can adversely reflect on us all.
B
Buck Harrison
Hunter Plumbing
I have a 2001 420. It came delivered with the (RV style) shore-side water hookup that you are all describing. I use it extensively when tied up, but with respect.... (completely unhooking the hose when I leave the boat). I have not had any problems with leaks, etc. which leads me to believe that the plumbing as installend on this model, at least, is designed for shore-side pressures. I would suggest asking the service department at your dealer about whether the plumbing in your specific model can handle shore-side pressure. I suspect that (if it is a late model Hunter) it can, since, I believe, Hunter uses the same (Whale) hose/fittings on all of its models.
I have a 2001 420. It came delivered with the (RV style) shore-side water hookup that you are all describing. I use it extensively when tied up, but with respect.... (completely unhooking the hose when I leave the boat). I have not had any problems with leaks, etc. which leads me to believe that the plumbing as installend on this model, at least, is designed for shore-side pressures. I would suggest asking the service department at your dealer about whether the plumbing in your specific model can handle shore-side pressure. I suspect that (if it is a late model Hunter) it can, since, I believe, Hunter uses the same (Whale) hose/fittings on all of its models.
S
Scott
Thanks
Thanks to all. I actually just want to have a quick connect built into the hull somewhere by the power couplings. I only plan to use it to fill the tanks without having to run to the front all the time. Scott.
Thanks to all. I actually just want to have a quick connect built into the hull somewhere by the power couplings. I only plan to use it to fill the tanks without having to run to the front all the time. Scott.
P
Peggie Hall/Head Mistress
NO boat plumbing can withstand shoreside pressure
You haven't had any problems with yours because your system includes a pressure reducer valve. All shore water connections have to include one...the difference in pipe size--from a 1" hose on the dock to a 1/2" hose makes it necessary. If you doubt that, block half the end of a garden hose with your thumb and see how much it increases the pressure. I suggest you keep a spare valve on hand...and that you not only disconnect it when you leave the boat--even if it's only for an hour, but when you go to bed at night. It was right here on this site about a year ago (maybe longer) that someone posted his story of waking up in the middle of the night to use the head (I wonder why?) and stepped out of bed into water almost to the top of his v-berth.
You haven't had any problems with yours because your system includes a pressure reducer valve. All shore water connections have to include one...the difference in pipe size--from a 1" hose on the dock to a 1/2" hose makes it necessary. If you doubt that, block half the end of a garden hose with your thumb and see how much it increases the pressure. I suggest you keep a spare valve on hand...and that you not only disconnect it when you leave the boat--even if it's only for an hour, but when you go to bed at night. It was right here on this site about a year ago (maybe longer) that someone posted his story of waking up in the middle of the night to use the head (I wonder why?) and stepped out of bed into water almost to the top of his v-berth.
P
Peggie Hall/Head Mistress
Scott, I suggest you offer us an opportunity to
review just how you plan to tap into your boat's plumbing to do that and where BEFORE you commence any surgery on it. That's not quite as simple as it sounds.
review just how you plan to tap into your boat's plumbing to do that and where BEFORE you commence any surgery on it. That's not quite as simple as it sounds.
D
Daniel Jonas
Pressure
Peggy, The hose size has nothing to do with pressure in the dock side vs boat pressure. Pressure in the system (when closed) is constant throughout any piping system. Does not matter what hose size you move to (up or down). The pressure increase you cause by putting your finger over an open hose creates a pressure increase because it is not a closed system. If you could hold your finger over the hose and completely stop the flow, your finger would have the total system pressure against it. Same as the hoses in the system or in the boat. A hose hooked to a boat from shore would be a closed system. I agree that boat systems would not contain many, if not most, shore side water system pressures reliably (some are actually very low). But the requirement for a pressure reducer is not caused by the reduction in hose size. It is simply a function of the utility water pressure in your area, against the water pressure your fixtures or piping system can mantain, or in the case of irrigation, the pressure range the spray heads are designed for. I think the most interesting thing coming out of this discussion is that just about everyone agrees that the hose should be completely disconnected from the boat (not just shut off) anytime you are not awake and on the boat. Does not sound like a fail-safe system to me. Would you accept that condition for hooking water to your house? Dan Jonas (S/V Feije II)
Peggy, The hose size has nothing to do with pressure in the dock side vs boat pressure. Pressure in the system (when closed) is constant throughout any piping system. Does not matter what hose size you move to (up or down). The pressure increase you cause by putting your finger over an open hose creates a pressure increase because it is not a closed system. If you could hold your finger over the hose and completely stop the flow, your finger would have the total system pressure against it. Same as the hoses in the system or in the boat. A hose hooked to a boat from shore would be a closed system. I agree that boat systems would not contain many, if not most, shore side water system pressures reliably (some are actually very low). But the requirement for a pressure reducer is not caused by the reduction in hose size. It is simply a function of the utility water pressure in your area, against the water pressure your fixtures or piping system can mantain, or in the case of irrigation, the pressure range the spray heads are designed for. I think the most interesting thing coming out of this discussion is that just about everyone agrees that the hose should be completely disconnected from the boat (not just shut off) anytime you are not awake and on the boat. Does not sound like a fail-safe system to me. Would you accept that condition for hooking water to your house? Dan Jonas (S/V Feije II)
M
Mickey McHugh
Simple Water Hookup
We live aboard and were tired of hearing the pump run and filling tanks so I hooked up what I think is a safe way to use shore water. Now all we have to do is remember to turn off the water whenever we leave or turn in for the night. Yaga is our home so we NEVER forget. It was a habit easy to start and keep. I have a transom shower fixture so I put a tee in the cold water supply grey piping going to it. I installed a non-regulated Perko chrome plated bronze deck fitting for connecting the water hose in the transom next to shore power fittings. On the inside of the fitting I connected a 1/2 inch ball valve (sort of like a thru hull setup). From the ball valve, I ran water piping about 3 feet to the tee using the same kind of piping Hunter used. I use a brass water pressure regulator at the pier faucet, then a short hose to a water filter, then a hose to the deck fitting. I use those Velcro straps to hold the 2 shore power cables, the phone cable and water hose together. The ball valve is necessary to prevent leaking back through the deck fitting that only has a cap that tends to leak. It also allow us to shut off the shore water supply without getting off the boat. With this system you can not fill the water tanks since water does not flow back through the water pump. Going on 5 years now and no problem AND I know Peggy 'It's only a matter of time before that regulator fails'. So I will replace it when I get back from Russia. OR maybe I'll get one of those super quiet pumps. Yeah, that's the ticket!! ;^) LOL Mickey and Debbie
We live aboard and were tired of hearing the pump run and filling tanks so I hooked up what I think is a safe way to use shore water. Now all we have to do is remember to turn off the water whenever we leave or turn in for the night. Yaga is our home so we NEVER forget. It was a habit easy to start and keep. I have a transom shower fixture so I put a tee in the cold water supply grey piping going to it. I installed a non-regulated Perko chrome plated bronze deck fitting for connecting the water hose in the transom next to shore power fittings. On the inside of the fitting I connected a 1/2 inch ball valve (sort of like a thru hull setup). From the ball valve, I ran water piping about 3 feet to the tee using the same kind of piping Hunter used. I use a brass water pressure regulator at the pier faucet, then a short hose to a water filter, then a hose to the deck fitting. I use those Velcro straps to hold the 2 shore power cables, the phone cable and water hose together. The ball valve is necessary to prevent leaking back through the deck fitting that only has a cap that tends to leak. It also allow us to shut off the shore water supply without getting off the boat. With this system you can not fill the water tanks since water does not flow back through the water pump. Going on 5 years now and no problem AND I know Peggy 'It's only a matter of time before that regulator fails'. So I will replace it when I get back from Russia. OR maybe I'll get one of those super quiet pumps. Yeah, that's the ticket!! ;^) LOL Mickey and Debbie
P
Peggie Hall/Head Mistress
I THINK you're missing the point, Dan...
Any time that pipe size is reduced, pressure of a constant flow increases...increasing pipe diameter reduces pressure. I only used the analogy of blocking the end of the garden hose because it's the easiest for folks to visualize...a garden hose nozzle works on the same principle--it reduces the diameter, which increases the pressure. Dock water coming out of a faucet connected to the boat is flowing through a 1" hose that connects to 1/2" plumbing. Without a pressure reducer valve, the pressure has to increase for the same volume and rate of flow when the radius of the pipe decreases. As for "fail safe" methods on boats vs houses...there are also many "failsafes" required on land that require attention... For instance, you wouldn't leave the house without unplugging an iron. But a boat ISN'T a house, or even a floating condo. For one thing, houses can't sink. But more importantly, everything in a house is just an appliance, but everything on a boat is part of a complete system. A boat is completely self-sufficient...generates its own power, has a complete sewage system, its own fresh water reservoir and internal water "main," etc. A boat is effectively a small town, and the owner is the city manager. Unfortunately, that's a concept too many boat owners never grasp.
Any time that pipe size is reduced, pressure of a constant flow increases...increasing pipe diameter reduces pressure. I only used the analogy of blocking the end of the garden hose because it's the easiest for folks to visualize...a garden hose nozzle works on the same principle--it reduces the diameter, which increases the pressure. Dock water coming out of a faucet connected to the boat is flowing through a 1" hose that connects to 1/2" plumbing. Without a pressure reducer valve, the pressure has to increase for the same volume and rate of flow when the radius of the pipe decreases. As for "fail safe" methods on boats vs houses...there are also many "failsafes" required on land that require attention... For instance, you wouldn't leave the house without unplugging an iron. But a boat ISN'T a house, or even a floating condo. For one thing, houses can't sink. But more importantly, everything in a house is just an appliance, but everything on a boat is part of a complete system. A boat is completely self-sufficient...generates its own power, has a complete sewage system, its own fresh water reservoir and internal water "main," etc. A boat is effectively a small town, and the owner is the city manager. Unfortunately, that's a concept too many boat owners never grasp.
J
John Van Stone
Peggy, I beg to differ with you
Peggy I hate to differ with you, but the need to reduce pressure is not related to the pipe size but to the static pressure of the shoreside water supply which is higher than our systems can take. The max pressure that is going to occur in the system is the static pressure(when there is no flow) and when ever there is flow the pressure will fall. While you are right that the smaller the pipe the higher the pressure for any flow rate, when there is no flow the pressure is the same whether the pipe is 2 inches or 1/8 inch. The point that there needs to be a pressure reduction however is correct and that is the most important point.
Peggy I hate to differ with you, but the need to reduce pressure is not related to the pipe size but to the static pressure of the shoreside water supply which is higher than our systems can take. The max pressure that is going to occur in the system is the static pressure(when there is no flow) and when ever there is flow the pressure will fall. While you are right that the smaller the pipe the higher the pressure for any flow rate, when there is no flow the pressure is the same whether the pipe is 2 inches or 1/8 inch. The point that there needs to be a pressure reduction however is correct and that is the most important point.
J
John Van Stone
no increase in pressure at the end of a hose
Peggy: By the why there is no increase in pressure at the end of the hose when you put your finger over the end. The reason that water goes further is the the pressure gradient between the hose and the outside is affecting a smller volume of water and therefore goes farther. Also fluid mechanics are different than electrical and in a pipe of varying size with constant flow there is not a step up of pressure within the pipe with a decrease in size.
Peggy: By the why there is no increase in pressure at the end of the hose when you put your finger over the end. The reason that water goes further is the the pressure gradient between the hose and the outside is affecting a smller volume of water and therefore goes farther. Also fluid mechanics are different than electrical and in a pipe of varying size with constant flow there is not a step up of pressure within the pipe with a decrease in size.
D
Daniel Jonas
Pressure
Thanks John. I do agree that for an equal flow rate (volume) the pressure will be higher in a small pipe vs a large. But again, this does not occur on a shore to boat system, because the pressure is limited by the static capability of the shore side system. Because of that you will just get less volume out of the smaller pipe. Peggy, I did not miss the point, although I suspect you won't concede. The only thing I questioned was your assertion that the smaller pipe was the cause of higher pressure and the need for a pressure reducer. Even in your response you still view a water system as open rather than closed. Unless you run the water on the boat 100% of the time, you have to design for static pressure, which will be the highest pressure the system will see. When you open a valve or faucet the pressure drops at that point....that is why the water comes out...there is more pressure on the other side of the system. Beyond that you were making points in response to my correction that are irrelevant to my comment. I agreed that a presure reducer is necessary, in fact if you review my posts, I don't advocate hooking to shore water at all. I do know that boats are a system, and require the understanding of someone who understands the interelationship of those systems, and the ability to get killed from not understanding the same. Comes from 30 years with airplanes where that understanding can be taxed over a period of seconds, in addition to my sailing experience, where it seems to happen in slow motion by comparison. Believe it or not, there are some of us that not only know our boat systems, we understand the theory behind systems and even the physics of how they work. And I apologize in advance ( ok, just after) for the rant. Dan Jonas (S/V Feije II)
Thanks John. I do agree that for an equal flow rate (volume) the pressure will be higher in a small pipe vs a large. But again, this does not occur on a shore to boat system, because the pressure is limited by the static capability of the shore side system. Because of that you will just get less volume out of the smaller pipe. Peggy, I did not miss the point, although I suspect you won't concede. The only thing I questioned was your assertion that the smaller pipe was the cause of higher pressure and the need for a pressure reducer. Even in your response you still view a water system as open rather than closed. Unless you run the water on the boat 100% of the time, you have to design for static pressure, which will be the highest pressure the system will see. When you open a valve or faucet the pressure drops at that point....that is why the water comes out...there is more pressure on the other side of the system. Beyond that you were making points in response to my correction that are irrelevant to my comment. I agreed that a presure reducer is necessary, in fact if you review my posts, I don't advocate hooking to shore water at all. I do know that boats are a system, and require the understanding of someone who understands the interelationship of those systems, and the ability to get killed from not understanding the same. Comes from 30 years with airplanes where that understanding can be taxed over a period of seconds, in addition to my sailing experience, where it seems to happen in slow motion by comparison. Believe it or not, there are some of us that not only know our boat systems, we understand the theory behind systems and even the physics of how they work. And I apologize in advance ( ok, just after) for the rant. Dan Jonas (S/V Feije II)
P
Peggie Hall/Head Mistress
I'm always willing to concede when I'm wrong...
And even more willing to learn! And since you and John seem to know what you're talking about, I'll take advantage of the opportunity to learn from you. We agree that pressure increase as hose diameter decreases. The issue is static pressure vs. flowing pressure...right? It's my understanding that water flowing through a 1" pipe will be under less pressure than water flowing through 1/2" pipe, that reducing the pipe/hose size increases the pressure. Unless a faucet is open, the system is under static pressure...in fact, opening a faucet would actually RELIEVE pressure. So far, so good? If so, here's where I THINK we broke down: it's the static pressure--which exists 99% of the time, especially when no one is aboard or awake to run water--that causes the problems. It's putting constant pressure on every joint--wye, tee--in the system. If it's greater than the plumbing can withstand, one of those connections is gonna blow. Which is why a pressure reducer is necessary in the system--to drop the pressure that the 1" hose coming into the boat can handle to a level that won't rupture the 1/2" plumbing on the boat. Have I got it right? If not...where did I go wrong?
And even more willing to learn! And since you and John seem to know what you're talking about, I'll take advantage of the opportunity to learn from you. We agree that pressure increase as hose diameter decreases. The issue is static pressure vs. flowing pressure...right? It's my understanding that water flowing through a 1" pipe will be under less pressure than water flowing through 1/2" pipe, that reducing the pipe/hose size increases the pressure. Unless a faucet is open, the system is under static pressure...in fact, opening a faucet would actually RELIEVE pressure. So far, so good? If so, here's where I THINK we broke down: it's the static pressure--which exists 99% of the time, especially when no one is aboard or awake to run water--that causes the problems. It's putting constant pressure on every joint--wye, tee--in the system. If it's greater than the plumbing can withstand, one of those connections is gonna blow. Which is why a pressure reducer is necessary in the system--to drop the pressure that the 1" hose coming into the boat can handle to a level that won't rupture the 1/2" plumbing on the boat. Have I got it right? If not...where did I go wrong?
- Status
- Not open for further replies.