Sanitary Hose Barb Fittings

[John T1594]

I will be replacing the sanitary hose on my H340 soon and would like to change some of the tank fittings that might be cracked. I have had problems in the past with barb fittings that would not fit inside the hose - but with much swearing and sweat. Most of the catalogs list barb fittings as 1.5" but don't say if that is the ID or OD. Any advice?

 

[Don S/V ILLusion]

size matches hose

JohnThe size quoted is typically indicative of what size (ID) hose will fit it. Just use a heat gun set on low to soften the hose ends to make them easier to slide on/off. Hot water works as well.

 

[Maine Sail]

Be careful..

Be very, very careful using a heat gun to soften the "white" sanitary hose. You can permanently change the characteristics of this hose with to much heat, ruin it and make it considerably weaker. Hot water is far safer. If you can't get an end of the hose into hot water soak a rag in hot water and wrap the hose in it but wear insulated, water proof, ski gloves, so you don't burn your hands on a 200+ degree rag.. Another method I've used is to soak a length of iron pipe, with the thread end cut off, that is slightly smaller than the ID of the hose in boiling water. Once it's the same temp as the boiling water insert it into the hose end, slightly further than the length of the hose barb, and let the heat from the iron pipe soften the hose from the inside out.Again, heat guns can be dangerous, if used improperly, with sanitary hose...

 

[Daryl]

Hose Repalcement

Sealand makes adapters that allow you to merge from sanitation hose to PVC pipe. I suggest you throw away all the long runs of sanitation hose and install PVC because it will last forever and cost a lot less. Normal hose barbs are too large for sanitation hose

 

[windward54]

Don't forget to lube it up!

I've also used K-Y Jelly to help get a tough sanitation hose over a barb. Works great and is cheaper then the hose lubricants that I have bought in the past.

 

[Peggie Hall HeadMistress]

Avoid 1.5 gray PVC thread-barb fittings

Stated fittings sizes are always the OD (outer diameter) and stated hose sizs are always the ID (inner diameter)...with one exception: For reasons I've never been able to learn in 20 + years, nominal 1.5" thread x 1.5" barb gray PVC fittings are ACTUAL 1.5" thread OD x 1.5" barb ID...the barb OD is 1 5/8", making it d'd near impossible to get a 1.5" hose onto one of 'em no matter how much you heat it. This is only true of 1.5" gray PVC, no other size. Marelon and nylon fittings are actual 1.5" x 1.5". As others have said, it's best to avoid using a heat gun unless you really know what you're doing with one...'cuz over-heating a hose will damage it. They like hot water...I've always preferred a blow dryer. NEVER heat a hose to make it bend tighter than it wants to bend willingly...that can cause the outside of the bend to stretch enough to tear and weaken the inside of the bend enough to kink. If the bend is tighter than the hose will bend willingly, break the hose and use an inline radius fitting.Lubricate the inside of the hose and the outside of the fitting with dishwashing liquid, or better yet, K-Y. Don't use any grease or oil as a lubricant. And don't use any sealant on the thread except maybe some teflon tape. Be very careful NOT to over-tighten threaded fittings. One full turn past hand tight, plus enough to aim an elbow where it needs to go is all, even if threads are still showing. Tank fittings are NPT standard, which is very slightly tapered...cranking 'em down too much will crack the "collar" in the female tank fitting, if not immediately, once the tank is subject to expansion and contraction due to temperature changes. Double clamp all hose connections, putting scews on opposite sides of the hose...or at least 90 degrees apart if access makes 180 impossible.And finally, use only plastic fittings in plastic tanks...never SS or any other metal. Plastic and metals have very different thermal co-efficients--which is the fancy way of saying they expand and contract at different rates and in different amounts...which can result in a cracked female tank fitting or a leaking fitting.

 

[Joseph Shirley]

I believe the gray PVC fittings were made to an RV standard.

I have some on my boat and had to get replacement fittings from an RV supplier.Joe S

 

[John Nantz]

And.... (another "Don't") Don't cut old hose across the barbs

Seems like sometimes there are a lot of "don't" in advice and here's another one that's not been mentioned. To get the old hose off - which can be really, really hard - it's often easy to take that utility knife and slit it across the barbs. Well, don't do it that way because if it cuts into the plastic barbs that is one place where "it" (and you know what I mean) can LEAK! Even just a little bit. And, then there is ... ugh....o-d-o-r.

 

[Peggie Hall HeadMistress]

John is right...don't cut...use heat instead

Heating the end of the old hoses softens and expands 'em enough to let you pull 'em off fairly easily and doesn't damage the fitting.Joe...why would you want to hunt down fittings that are impossible to get a hose onto instead of replacing 'em with fittings sized for 1.5" sanitation hoses???

 

[Joseph Shirley]

Peggie, sorry to mislead you.

The fittings I referred to were smaller size for a water system not the 1.5" that you talked about. They were only available however, through RV or Trailer Suppliers, but I think the larger grey PVC are also used primarily for RV's.Joe S

 

[John Nantz]

Thanks, Peggy, for the "what to Do"

Thanks for tagging onto my "don't" with your what to "do". You're always so nice and helpful!-= John =-

 

[sail aweigh]

Head hose

Hi I'm new here so I hope I'm asking this question at the right place. My head hose is still in good shape but I need to clean the inside,Is there a solution of vinigar or something that I can pour inside to loosen that stuff? Its the hose from the head to the Yvalve only. Thanks Dan...

 

[Peggie Hall HeadMistress]

Distilled white vinegar should solve your problem

And btw...yes, you're in the right place.IF your problem is sea water mineral buildup, then a cupful of undiluted distilled white vinegar (NOT cider, wine or balsalmic!) flushed into the line will dissolve it...though if you have a heavy buildup it may take more than one application. You say it's only between the toilet and y-valve, but if it's one place, it has to be in the rest of the lines...though maybe not as much.So first, flush a cup--less if less is needed to fill the line without leaving any in the bowl--of white vinegar into the line between the toilet and y-valve...let it stand overnight, then open the valve and let it go into the line between the y-valve and thru-hull. Let that stand overnight, then open the thru-hull and let it drain. Turn the valve to the tank...flush another cupful through to the tank.That'll start it dissolving. To dissolve the rest--and to prevent buildup in the future, flush a cupful through each section of hose once a week.

 

[sail aweigh]

Thanks Head Mistress

Thanks a lot Peggie, I'll try that. My yvalve is directly above the thru-hull, and the valve was stuck in the open position(overboard discharge) when I purchased it last year. This is why its the only hose that needs cleaning. I got the valve working again and i'm able to use my holding tank that has never been used. Dan IP31-108