Fresh water system info for owner's with newer (2000's?) boats

Jun 3, 2010
177
Hunter 27-3 Erie
As a reference for those of you that have Hunter's built recently. I don't have exact dates but hopefully I have enough information for you to figure your boat out. We have had issues with our fresh water system since we took possession of the boat at the end of last August. Some were due to parts that were broken by the mechanic that did the winterizing for the previous owner..........OK, a lot had to do with that. The PO really did not use it a lot so there is a huge sanitizing project that is going to happen with spring commissioning. What I would like to share with you is information I had to learn along the way.

Our boat is plumbed entirely with PEX tubing, red for hot water, blue for cold. Having used household PEX I can tell you that it is a strong product that resists freeze damage which is important up north. The PEX used on our Hunter's is the Sea Tech brand, along with their own line of plastic PEX fittings. There are similar products out there but OEM is Sea Tech and the only place I could find it is Hamilton Marine in Maine (disclaimer, I have no relationship with them). The tubing is 15mm in size if you want to add or replace. The beauty of the product is you only need to make a clean cut on the tubing using tubing cutters (NO hack saws or utility knives!!!), insert the tubing into the fitting until it seats and gently pull out to set the seal. There is an inner sleeve that pulls out of the fitting about 1/8". The fittings and tubing can also be disconnected and reused many times. I have added a photo of a Sea Tech fitting for reference. The second image is of the locking clip that SHOULD be inserted in each fitting to keep it engaged with the tubing. Once you gently pull out on the tubing and the inner sleeve slides out to engage the tubing, one of these clips need to be inserted to lock everything in place. When our Hunter was plumbed they only installed a few clips, the rest of the fittings can still move around and therefore LEAK. If you have pesky fresh water leaks into the bilge of your newer Hunter I strongly encourage you to take a few minutes and look over your plumbing fittings. (for example, I have a hot water connection that leaks under the galley and sprays everywhere when you pressurize the system.....sometimes, depending if the sleeve has moved in our out). My weekend project is to take my new bag of clips and start at the fresh water tank in the bow, tracing each PEX tube to each fitting and inserting clips where they are missing, all the way back to the transom shower. I hope my experience is helpful.
 

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Jun 3, 2010
177
Hunter 27-3 Erie
UPDATE: It took a little while but I did get a lot accomplished this past weekend. FYI, should your water pressure start to drop off, I found a screen on the input side of the pressure pump between the pump and the fresh water tank. It appears that the PO may have used the fizzy tablets to keep the tank water fresh. I was warned previously that using those will cause any filter screens in the system to clog. The one on the pump was just about clogged shut. I cleaned that and began putting the "C-clips" in place. I worked my way back and found several fittings under the galley sink, there is a fresh water manifold there which sends hot and cold water to all the sinks and showers. There are also fittings up under the galley sink and also the sink in the head that need to be inspected. There was a mixer on the output side of the hot water tank to keep you from getting scalded. I removed that at the end of the season and re-plumbed the tank in a traditional configuration. The mixer also had a screen in it that clogged every few minutes from the fizzy tablet residue. I figure I learned early on that if water coming out of a faucet is too hot I just add cold water.

There are two things left on the list, check the fittings on the transom shower for C-clips and once the weather gets warm, start filling and flushing the entire system with bleach water. I already know that the screen in the galley sink faucet will need to be removed during this process or it will clog. I am also thinking of pulling that screen on the pump at the same time until the system is clear. I will be removing the shower sprayer on the transom and in the head while flushing, they were clogged (and broken) when we bought the boat. I'm hoping I can get this done in one more weekend.
 
Dec 19, 2006
5,832
Hunter 36 Punta Gorda
I have had no problems with my fresh water system that you have had except breaking
the fitting at the inside of the stern shower and added a extension hose and also had the
screens in the hot water tank clog on the hot water side and the screens are in at the connection into the hot water heater and just need cleaning.
Nick
 
May 7, 2012
1,567
Hunter e33 Maple Bay, BC
but OEM is Sea Tech and the only place I could find it is Hamilton Marine in Maine
Sea Tech is owned by Watts Water Technologies. Given that pretty well every local plumbing store around carries Watts products, I would think that they would be able to get Sea Tech products in fairly easily. Many of the chandleries I have visited carry the Sea Tech line, even West Marine does.
 
Jun 3, 2010
177
Hunter 27-3 Erie
My West catalog must be outdated then, they did not have SeaTech, only Whale. That is a good tip on Watts Water too, I'm not a plumber and now that I think about it, I'm not even sure where a local plumbing store is???

One of the serious downsides of owning a boat in this area is that we really have no local options for buying parts. The only "chandlery" left is more of an after thought to the front room at a local mechanic. The nearest West Marine is 100 miles away in either Cleveland or Buffalo.
 
Oct 26, 2008
6,305
Catalina 320 Barnegat, NJ
Thanks for info on this. I've stripped out all the plumbing (and the water tank) on my boat and am starting from scratch.
I have plenty of 1/2" PEX left over from a house project and plan on using it in the boat. Are there any reasons not to use the products I have on hand versus the marinized Sea Tech brand? I note that fittings for my new faucets, tanks and water heater are all 1/2". You mention 15 mm diameter for the Sea Tech PEX, which is closer to 5/8" than it is to 1/2". Does that make a difference at 1/2" connections?
 
Jun 3, 2010
177
Hunter 27-3 Erie
I have left over PEX from a mountain cabin re-plumbing project, the 15mm SeaTech is substantially smaller in diameter than what was available at the home store. (The 15mm size is printed on the SeaTech PEX tubing and is referenced in the Hamilton catalog, I have no idea if that is an ID or OD dimension, no one specified). In the past I have run into the OD vs ID dimension problem in home plumbing supplies, maybe Hello Below can shed some light on this?
 
May 7, 2012
1,567
Hunter e33 Maple Bay, BC
maybe Hello Below can shed some light on this?
Will have to measure tomorrow when I am at the boat. I will also look at what is going on at the Kuuma water heater/Sea Tech connections. I don't remember anything special.
 
Sep 20, 2006
2,952
Hunter 33 Georgian Bay, Ontario, Canada
Thanks for info on this. I've stripped out all the plumbing (and the water tank) on my boat and am starting from scratch.
I have plenty of 1/2" PEX left over from a house project and plan on using it in the boat. Are there any reasons not to use the products I have on hand versus the marinized Sea Tech brand? I note that fittings for my new faucets, tanks and water heater are all 1/2". You mention 15 mm diameter for the Sea Tech PEX, which is closer to 5/8" than it is to 1/2". Does that make a difference at 1/2" connections?
15mm fittings will not work with 1/2" or vise versa. Have to use either metric or imperial.

Although I did not know about the clips, I've never had many problems with ours in 8 seasons, including a couple of VERY cold winters. I pull mine all apart at the hot water tank to winterize and put all back together in spring. Bought a few extra fittings to do this. I may just get the clips anyways as I did have one blow apart after I had pulled apart and only noticed while standing on the dock chatting with a beer in hand when the bilge pump came on.... Mind you, I do shut off water pump when leaving the boat.
 
May 7, 2012
1,567
Hunter e33 Maple Bay, BC
In the past I have run into the OD vs ID dimension problem in home plumbing supplies, maybe Hello Below can shed some light on this?
Sorry for the long delay, I only just went to the boat yesterday. The OD of the Sea Tech tube is 15mm. I don't have a piece laying about so I am not able to give you the tube ID.

I will also look at what is going on at the Kuuma water heater/Sea Tech connections. I don't remember anything special.
There are Sea Tech adapters available to allow the connection of the 15mm Sea Tech tube to various standard fittings such as the 1/2" brass fitting on my Kuuma water heater. I suppose also at your faucet fittings, etc.
 
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Aug 19, 2013
1
Hunter 36 Annapolis
Anybody have a link to detailed diagram and info on the fresh water manifold (I have a 2005 Hunter 36)? I got some valve associated parts (O-rings, valves, plastic flange clip type of thing, no "C-rings" though) and had a technician repair a leaking fitting before I winterized, but now I'm leaking again, and the tubular sleeve from a couple of hot water output hoses (to galley and shower) is loose, and can easily be pulled out. So I've turned off the valves and hoping to find info on how to re-secure. I would have thought there would be some sort of threaded ring to tighten.
 
Sep 20, 2006
2,952
Hunter 33 Georgian Bay, Ontario, Canada
Are the fittings that are leaking or loose, the black connectors? There is a ring that must be all the way out to lock the tubing in place. To remove the tubing you push in the ring and will release the tubing. If this ring is not pulled out, the tubing will be loose and most likely causing the leak.

http://www.seatechinc.com/Technical/Installations
 
Jun 3, 2010
177
Hunter 27-3 Erie
If you have the fittings that Scott describes you will need the C-clips to keep the ring in place. Once the tubing is inserted into the fitting, the ring is pulled out to engage the seal and the C-clip is pushed in place to keep the ring out. The C-clip keeps the ring from slipping back into fitting which is the release position.
 
Jun 11, 2011
1,243
Hunter 41 Lewes
Craig my boat came with a bag of those clips in the nav table. Thanks for letting me know what they're for. :biggrin: