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HMS_Beagle's avatar
HMS_Beagle
Explorer
Apr 16, 2013

Shower fixture replacement in a BF10.4E

I have complained about the poor quality of RV shower fixtures and also the weather. I can't do anything about the weather, but I did replace my shower fixture.

The factory installed the standard Phoenix POS plastic mixer:



This is almost entirely plastic, uses rubber washers for sealing just like a garden hose bib from the 1950s. The feel of the knobs when you adjust it is far worse than a cheap Chinese hose bib. It is very difficult to adjust for volume or temperature, such that you alternately get scalded and frostbitten. Completely unsuitable for a shower mixer, and too light weight for a door stop:



Suitable quality replacements are available from the yachting industry. This is a Scandvik mixer and bulkhead fitting machined from solid brass, chrome plated, ceramic cartridge single lever mixing valve. They are widely distributed through marine suppliers, I bought these at Defender online.



The components are like miniature versions of quality home fixtures. The mixer hooks up with supplied hoses.



I had to enlarge the hole from 1" to 1.25" for the mixer. Being unsure which side I wanted the mixer on, and realizing that the other hole was already too large for the bulkhead fitting (and would need a filler) I enlarged them both, that would allow me to swap them later if I changed my mind.



I had to make some adapters. The hoses are intended for 1/2 NPS (straight thread!) male, while the normal plumbing connection in the RV is 1/2 NPS female. You could probably just tighten them on a 1/2 NPT adapter, but I am accused of "obsessive attention to detail". Also to fill up the oversize hole I made the ring indicated in the picture, with a profile and diameter to match the mixer bezel. It was turned out of 316 stainless, which does not have the same polish as the chrome, but compromises have to be made.



Access on the BF10.4E is through a cover under the lav sink. When I say "access" you must do everything by feel, with one hand. It's a bit tricky and required some choice swear words. Connections are way up out of the picture, no way to get two arms in there.



The finished install. It works MUCH better that the POS plastic fixture, just flip it on in the middle and you are at least not going to get scalded or frozen, very easy to adjust and it stays adjusted.



At the same time, but really an independent problem, I replaced the shower sprayer with this Scandvik version. It looks (and sprays) a lot like a kitchen sink sprayer which is fine with me. The main advantage is that it is off until you push the lever. By "off" I mean not dribbling, leaking, dripping: OFF. You can turn the shower valve on and get it adjusted to your liking, then leave it that way for the duration of the trip if you like, just step in the shower and push the lever for water. In fact Scandvik makes a pure shower mixer (no shut off, just temp adjustment) if you prefer this. The sprayer will lock on by pulling the lever up, if you need that. This one is plastic, they make also a brass one in a different shape but it is heavy so when you drop it, it can chip the shower gelcoat.

9 Replies

  • One more thing I may do eventually: for some reason RV hot water heaters do not have a "tempering valve" on the output. The hot water capacity is modest, usually 6 gallons, so the temperature on them is set very high, giving you more usable volume of warm water because you mix in a large percentage of cold before use. However this raises the possibility of scalding, particularly when assisted by the horrible Phoenix fixtures. If you add a thermostatically controlled tempering valve on the hot water output, the cold water is mixed with the hot to automatically produce hot water into the system at a tolerable temperature - and more of it. Also it makes temperature adjustment at the faucet easier, since the hot water supply is a more constant temperature, unaffected (within limits) by the cycling of the hot water heater.
  • This is exactly the information that I've been searching for! Thanks for the info and the links - can't wait to convert mine!
  • I am considering going with a separate sink faucet with a single hole single lever, and a single lever shower mixer. Fortunately it does work as is, therefor not a crises project.
  • Scandvik and Ambassador make lav sink faucets with a shower diverter that would replace what you have. Another possibility is to replace the sink faucet with a single hole single lever, and put a single lever shower mixer in the other hole. If you look through their catalogs you will find a variety of possibilities.
  • Thanks for the feedback. My shower is part of the sink faucet. You lift a "do hickey" to change from sink to shower. I do not like the knobs on the sink, nor to I like having to lift the "do hickey" to change from sink flow to shower.

    I have considered changing the sink faucet and adding a separate shower mixing valve.

    Wayne
  • Thanks. Mixer is here at Defender. It is listed at $112 but they only charged me $97. Note that this model has a BSP outlet to the bulkhead sprayer hose fitting. The bulkhead fitting matching that is this one from Fisheries Supply at $35. Defender does not seem to list this one though I bet you could call them and get it (I like and recommend Defender - they are usually cost competitive and the customer service is good). Alternatively, do a Google search for "Scandvik 990047" (the mixer) and "Scandvik 10007" (the bulkhead elbow) to find many sources. The Scandvik link in the original post will get you to their catalog, there are many choices besides the one I used. Ambassador Marine is an other quality brand. The advantage of the parts I used is they will plug the existing holes for the Phoenix mixer.

    You will need a BSP coupling to connect the bulkhead elbow to the mixer outlet hose as they are both male thread. I got one from McMaster-Carr - you won't find them at Home Depot! - it is pn. 4860K676 on the referenced page, a 3/8 BSPP coupling. The coupling requires a gasket which is supplied with the bulkhead elbow, these are parallel threads and not self-sealing. A standard sprayer hose will fit the elbow outlet as it is 1/2 NPS.

    These hassles are because all of this marine stuff is imported from Europe, where British Standard thread is much more common than NPT. Whatever you order, take a close look at the specified inlet/outlet threads to be sure you have the right one or the right adapters. The above mentioned parts will work together, with the caveat that the hot and cold inlet is going to be a female 1/2 NPS. It will screw onto a 1/2 NPT and probably work (that's what a lot of people do) but it is not as secure as true 1/2 NPS. Most RV fixture inlets are 1/2 NPS, the straight thread is required so that the securing nuts can be run up against the bottom of the counter etc. So you could cut the tails off the old fixture and use those (though they are plastic). I machined some out of stainless on the CNC lathe, but I think a "real" plumbing store would have the right nipples.

    Oh, the sprayer is this one. I have this one in the boat, very nice solid brass, but as I said a potential chip hazard if you drop it. Also it does not lock on, have to hold the push button.
  • Great replacement, and a nice write-up. Do you have a link to the fixture, and what did it cost?

    Wayne