Installing handheld shower...

[IDBoating]

They make a sweet transom hatch I always wanted to install.

Did you know they're based in Rathdrum? Four miles from my house!

[IDBoating]

Finally dropped by HeaterCraft's offices. Really great people, super helpful. They don't expect much street traffic, though - even with their address finding them was a bit of a challenge.

They pulled out their shower control unit. There are three; flush mount, and two surface mounts (straight or right angle). They share a common valve assembly inside. See the photo earlier in this thread. They look nice in real life and I'd like to use one. Unfortunately, I don't think I'll be able to.

The main reason is flow restriction. I looked into the diassembled valve controls to find that the flow through each side must pass through a slightly off-round hole approximately 1/8th inch in diameter. That is darned small for a low-pressure system. The employee helping me at that point admitted they pass only about a gallon per minute max.

A secondary reason is hose fittings: Their valves use custom compression fittings which come preassembled to the hoses they supply. You cannot buy compatible fittings off the shelf. And the hoses they supply are extremely narrow, no more than 1/4 inch ID. This, again, contributes to low flow.

The parts exposed to water are made of two plastics, one that appears to be PVC and the other that appears to be glass-reinforced nylon. Those are good choices since they won't corrode in a marine environment. The two inputs (hot and cold) have integrated filter screens, another nice touch.

But the bottom line for me is flow restriction. I'm concerned that three lengths of 1/4 inch ID hose, with a 1/8th or smaller hole along the way, just won't flow enough water.

My next step is to research household fixtures in the hopes that I can find something 1) suitable for a marine environment, and 2) attractive on a boat. Household fixtures have pretty good flow rates, and use standard fittings permitting one's choice of hose diameter and type. I'm also going to check the RV market to see if there's something in that industry that might work.

[Wakeman22]

My mixing valve came off ebay and is an RV mixing valve. It allows for use of standard fittings and is small enough to fit in the area you wish. It was like only $10.00 or so with shipping. It is all plastic so it will be good in marine use. I still think you will need a pump to get the pressure and volume you desire.

[IDBoating]

Yep, so far I've found a couple of RV fixtures that look promising. Only one so far has given any sort of flow volume spec (2.2 GPM @ 60 PSI). Now that the boat is in storage I have all winter to look around for a good solution!

[IDBoating]

So far the most promising is this one from Phoenix Faucets:



They confirm that it uses plastic stem valves so it should be corrosion resistant. They don't publish a flow spec but they state it is "about 2.5 GPM at 60 PSI". I'd like that to be larger (indicating lower restriction) but it's the highest value I've found so far.

Also, it uses standard fittings so it should be possible to use larger, lower-restriction hoses.

[Wakeman22]

You may consider that the out side should go down so as to not interfere with a hose attachment.

[DacuuuCankle]

If you wish you can go with the Sprite Shower Filter that removes chlorine and pollutants from water.

[William_87]

You can use this shower valves, there are 7 options available to choose from.

I have tested it, their flow rate is also good.