Experience with SinkMi$er?

[Tejon7]

I just learned about the "SinkMi$er". Its a fancy diverter valve whos purpose is to conserve that initial blast of cold water when you turn on the hot water tap. It sends that cold water back to the fresh tanks (instead of down the drain). It comes with a little heat-sensitive bulb that changes color once the water is hot, letting you know that you can stop diverting water to the fresh tank and start your shower/dishes/whatever.

Link to product page HERE

Has anybody used one of these? Or has anybody made their own version? It's a little pricey at $80, but it seems like a pretty elegant solution that could potentially give you a few extra days boondocking if you use hot water frequently.

[TheHubbardBus]

I gotta be honest - that looks pretty cheesy to me. Particularly for the price. Isn't that valve 'chrome-look' plastic? Or poorly cast aluminum? And that T... what exactly is that made of? I don't trust it.

You could do exactly the same thing with much better components for much less money. A brass or stainless 3-way ball valve would probably cost $20 or less. A brass Tee chump change. The only thing you'd be missing would be the 'magic mushroom'. I'm guessing it would take you 2-3 tries before the amount of time needed for the water to run hot would be ingrained in your memory forever.

[Tejon7]

Ha! Yes, I imagine getting that timing wrong would be memorable

You're right that a DIY version may be better quality. I was mostly looking at the pictures of the brushed nickel option which look less plastic-ey, but now that I'm looking closer they do all look pretty low end. But... the magic mushroom! How will I shower without a magic mushroom?!

I actually already have parts for a more complicated system to divert and conserve that initial cold water, but wanted to see if anybody had seen this thingamajig in the flesh.

[dbsoundman]

How much cold water do you usually get in a skoolie or RV setup? I would think if your hot water heater was "hot and ready", the lines between the heater and the tap should be pretty short, so you would only capture a small amount of cold water before it turns hot...not sure what the volume of PEX pipe is but it can't be that much.

It's a nifty idea, but I'm just no sure if it's worth all the added complication.

[dbsoundman]

According to this site, 3/4" PEX pipe holds 1.83 gallons per 100 FEET of pipe. So let's say you have a long run between the hot water heater and shower, 30 feet...that's 0.3 * 1.83 = 0.549 gallons. In my planned build case, that run would be maybe 10 feet, so 0.183 gallons. Might as well just stick my water bottle underneath the tap and fill it up with the 24 oz of water I'd be otherwise wasting!

[Tejon7]

That's one way of doing it. In practice, I bet that quart of water will go down the drain for 90% of us, 90% of the time. Going and getting a bottle or a wash tub to catch that water isn't convenient, so the lazy among us (me) won't do it. When water usage is the main determining factor in how long you can go between resupply, it's worth the effort up front to build water conservation into the plumbing plan. At least for me it is, but my use case may be different that most.

[TheHubbardBus]

Originally Posted by Tejon7

But... the magic mushroom! How will I shower without a magic mushroom?!

It's tempting. But I think I'm just going to leave this one alone.

[TheHubbardBus]

Originally Posted by dbsoundman

According to this site, 3/4" PEX pipe holds 1.83 gallons per 100 FEET of pipe. So let's say you have a long run between the hot water heater and shower, 30 feet...that's 0.3 * 1.83 = 0.549 gallons. In my planned build case, that run would be maybe 10 feet, so 0.183 gallons. Might as well just stick my water bottle underneath the tap and fill it up with the 24 oz of water I'd be otherwise wasting!

Good point. I ran the numbers for 3/8 vs 1/2" ID pex, in our short bus, and it made a significant difference. My plan was to use 3/8 for everything (it would have met our flow requirements), but realized finding anything in 3/8, especially fittings, was close to impossible. So we reluctantly went up to 1/2". Can't imagine it's very likely 3/4" would be required for many, if any, bus builds.

[djdalfaro]

I have thought about doing something similar to this using a thermostatic trap valve on a rollback line. The valve I found was quite pricy ~$275. https://www.centromrosupply.com/Ther...Close-100F378C

Here's the post I made on it. https://www.skoolie.net/forums/f50/p...tml#post457639

[HamSkoolie]

If water conservation is a concern don't pipe hot water to the shower. You'll save TONS of water.

[shorthair]

Originally Posted by HamSkoolie

If water conservation is a concern don't pipe hot water to the shower. You'll save TONS of water.

🙃superb idea, showering in ice water will save even more water as we hurry to get out and dry off so we can warm up.

[HamSkoolie]

Originally Posted by shorthair

🙃superb idea, showering in ice water will save even more water as we hurry to get out and dry off so we can warm up.

EXACTLY....or go ahead and try the 1970's Cali drought method of showering with a friend. Silly Californian's, for some reason they used much more water showering with a friend than alone. Go figure!