I have stupid questions....

[Delos356]

Okay I have a series of dumb questions. I've done a lot of basic plumbing before for my house, and I'm pretty familiar with the really basic stuff, like PEX and fittings and basic PVC stuff. But I have been thinking a lot about how some of that may not apply to a bus or might apply differently, because of the vibrations and movement and pressure differences and importance of water conservation. Plus everything is above ground, and even if you insulate it's still more susceptible to freezing that if it was in your house.

So here are a few things I was thinking, and if anyone could correct me or redirect me that would be awesome. For now things are just layed out but not in stone so it's not too late to change or make improvements!

For my fresh lines I was going to use pex
- 3/4" for the main line, and each branch off would be 1/2"
-Instead of sharkbite fittings I am going to use actual crimp clamps for durability. I have brass fittings because I like them for durability but I heard the black plastic ones are actually less likely to freeze/burst
- I'll have 2 sinks and a shower, no water for the toilet (it's just me), so I was thinking 1 main line for hot and one for cold, with each branching off at the appropriate spot?
-I got a pump rated for 1.5gpm flow, is that enough? I thought about a 3 gpm but do I really want to waste so much water accidently?
- I will put all the plumbing on one side of the bus, within 7-8 feet of each other.
-fresh tank under the bed, right behind the shower, and propane hw heater in a cabinet in the bathroom that I can vent easily.

For the drains, I have access to a BUNCH of heater hose, all 1" diameter. Seriously maybe 100 feet of it. I can get bigger from work if I need. I know typically a drain would be 1.5 pvc, but with the wall cavity being pretty small and needing the hose to not burst/vibrate loose, etc- would the heater hose be okay for grey water drains?
-for the drain lines, do you run each one out the floor as soon as possible? Or would i run it down the wall and then out the floor to the tank?
-on the Hepvo valves, do you do a single one in line before the grey tank, or one at each drain source like you would a P trap?

Lastly- my dad restores old cars and has several fuel tanks laying around that have been drained and cleaned, and he offered me one to modify into a grey tank. Is there any reason why I couldn't use this? It would fit really nicely under my bus, and I can add the drain (outlet) fitting pretty easily I think.

Thanks guys!

[Danjo]

There are no stupid questions on this forum, only stupid answers!

[Delos356]

Oh hey- one more dumb question!!!

I was thinking about doing a glass shower door as the door to my bathroom, is that glass safe for a bus? I like the idea of not closing off an already small space, if I can, but want something more substantial than a shower curtain.

[Danjo]

PEX is awesome! I am a convert. Your fresh water plan looks fine. I have a 2 GPM pump. It’s plenty. If anything you’ll be looking for ways to restrict flow so you don’t blow through your water so fast. My PEX is all 1/2” and works great. Insulate it with pipe insulation if you can.

All my plumbing is ABS, but I hear of others using spa hose which is like what you have. The only problem I see is making bends. You can use some PVC for that.

The answer to running drain is to run it wherever you can, with the emphasis on a generally downhill trajectory. I put it this way because unlike a house, a bus can be on a slope.

I don’t have experience with Hepvo traps, but you’ll probably be fine with one just before the tank


A steel gas tank will work for your grey tank, though filling it with water is likely to shorten its life unless you line it with something like undercoating or bed liner.

[Danjo]

Originally Posted by Delos356

Oh hey- one more dumb question!!!

I was thinking about doing a glass shower door as the door to my bathroom, is that glass safe for a bus? I like the idea of not closing off an already small space, if I can, but want something more substantial than a shower curtain.

That glass is tempered and pretty tough. A good slam though and it might be a pile of glass crumbs. Should be fine though

[Danjo]

Oh, 1” diameter is a little small for a drain, but only because of stuff building up in there. I would personally go 1 1/2”.

[Danjo]

WhT about the water heater? Is it going to be properly vented? Don’t want anyone on this forum on page 5 of the local paper for asphyxiation

[Delos356]

Originally Posted by Danjo

WhT about the water heater? Is it going to be properly vented? Don’t want anyone on this forum on page 5 of the local paper for asphyxiation

Definitely vented- that's why it's not going under the bed! lol
Plan was to build out a cabinet in the wall behind the toilet, and vent it up from there, or straight out the wall, or both.

[Jay Brand]

Originally Posted by Danjo

That glass is tempered and pretty tough. A good slam though and it might be a pile of glass crumbs. Should be fine though

I am a glass estimator/installer and I agree with Danjo. Tempered glass is tough but it still is glass so one hard braking incident could shatter it.
Make sure you can secure the door, slider panel etc.... So when your driving it does not move.
You will definitely have to have a custom door or slider made. It's highly doubtful you will find a kit that will fit a bus application. If a glass door is what you want, find your door then build your enclosure to fit it.
Also something to remember, a glass shower door is not a submarine hatch, it will have small droplets that will slip through.

[o1marc]

HepVo and "P" traps are for keeping odor from backing up, with a Hepvo, put it right before the tank.

[Rucker]

Originally Posted by Delos356

Oh hey- one more dumb question!!!

I was thinking about doing a glass shower door as the door to my bathroom, is that glass safe for a bus? I like the idea of not closing off an already small space, if I can, but want something more substantial than a shower curtain.

As long as you use a real shower door you should be fine. Shower doors use tempered glass which does not shatter like regular glass.

[Rucker]

Originally Posted by Delos356

Okay I have a series of dumb questions. I've done a lot of basic plumbing before for my house, and I'm pretty familiar with the really basic stuff, like PEX and fittings and basic PVC stuff. But I have been thinking a lot about how some of that may not apply to a bus or might apply differently, because of the vibrations and movement and pressure differences and importance of water conservation. Plus everything is above ground, and even if you insulate it's still more susceptible to freezing that if it was in your house.

So here are a few things I was thinking, and if anyone could correct me or redirect me that would be awesome. For now things are just layed out but not in stone so it's not too late to change or make improvements!

For my fresh lines I was going to use pex
- 3/4" for the main line, and each branch off would be 1/2"
-Instead of sharkbite fittings I am going to use actual crimp clamps for durability. I have brass fittings because I like them for durability but I heard the black plastic ones are actually less likely to freeze/burst
- I'll have 2 sinks and a shower, no water for the toilet (it's just me), so I was thinking 1 main line for hot and one for cold, with each branching off at the appropriate spot?
-I got a pump rated for 1.5gpm flow, is that enough? I thought about a 3 gpm but do I really want to waste so much water accidently?
- I will put all the plumbing on one side of the bus, within 7-8 feet of each other.
-fresh tank under the bed, right behind the shower, and propane hw heater in a cabinet in the bathroom that I can vent easily.

For the drains, I have access to a BUNCH of heater hose, all 1" diameter. Seriously maybe 100 feet of it. I can get bigger from work if I need. I know typically a drain would be 1.5 pvc, but with the wall cavity being pretty small and needing the hose to not burst/vibrate loose, etc- would the heater hose be okay for grey water drains?
-for the drain lines, do you run each one out the floor as soon as possible? Or would i run it down the wall and then out the floor to the tank?
-on the Hepvo valves, do you do a single one in line before the grey tank, or one at each drain source like you would a P trap?

Lastly- my dad restores old cars and has several fuel tanks laying around that have been drained and cleaned, and he offered me one to modify into a grey tank. Is there any reason why I couldn't use this? It would fit really nicely under my bus, and I can add the drain (outlet) fitting pretty easily I think.

Thanks guys!

I used Pex crimp clamps, not sharkbite. Both seem fine but Pex is very reliable-I can wrench around the line and they do not leak.

I did NOT use plastic connectors. Not sure if they are bad, I just wanted a pretty bulletproof system.

Half inch lines seem fine if you're not making long runs however if you have an instant water heater you'll need to keep the pump close to the heater. Those water heaters need a minimum flow of water, input water temperatures within a range, and a minimum of water pressure, which may be hard to hold when you first open the faucet.

[Danjo]

Originally Posted by Rucker

I used Pex crimp clamps, not sharkbite. Both seem fine but Pex is very reliable-I can wrench around the line and they do not leak.

I did NOT use plastic connectors. Not sure if they are bad, I just wanted a pretty bulletproof system.

Half inch lines seem fine if you're not making long runs however if you have an instant water heater you'll need to keep the pump close to the heater. Those water heaters need a minimum flow of water, input water temperatures within a range, and a minimum of water pressure, which may be hard to hold when you first open the faucet.

Yep yep yep

[Delos356]

Thank you guys for all the help! This is the water heater I am looking at, because it doesn't require venting (I'm still going to vent it) and it only requires 2 psi of pressure to start. I'll still have the heater mounted less than 2-3 feet away from the pump though.
Where does the accumulator go? After the pump, before the heater?

https://www.amazon.com/dp/B0977N2DB3...v_ov_lig_dp_it

[Rucker]

Originally Posted by Delos356

Thank you guys for all the help! This is the water heater I am looking at, because it doesn't require venting (I'm still going to vent it) and it only requires 2 psi of pressure to start. I'll still have the heater mounted less than 2-3 feet away from the pump though.
Where does the accumulator go? After the pump, before the heater?

https://www.amazon.com/dp/B0977N2DB3...v_ov_lig_dp_it

Accumulator goes anywhere on the pressurized system but preferably right after the pump.

I've seen some youtube videos on the installation of that particular unit, so that's somewhere to look.

I also recommend mocking up your water system and testing the water heater out. You may not need a shower mixer valve and in fact a mixer valve may prevent the water heater from working correctly-it's designed, as best as I can tell, to produce hot water at the final temperature.

When I commissioned my system I got a feel for how mine worked, and ended up redoing the plumbing to accomodate.

For instance, I had a hot water recirculation system to create a little more volume of hot water and get rid of the initial blast of cold water. Didn't work, because the hot water coming back into the inlet valve would trip the inlet high temp monitor and the unit would not come on.

Also, I had a backflow valve as part of that system that restricted flow just enough that the inlet water pressure dropped below threshold to fire the unit up. If I ran two faucets, it would come on, and stay on if I shut one off. But one faucet alone was not enough demand on the Shurflo pump to keep the pressure above minimum (since it had to force the one-way backflow valve).

Got rid of both the recirc system and the backflow valve and the heater ran perfectly. The initial shot of cold water is brief and won't drain the tank, so I'm going to leave it that way for now.

I now know much more about how that heater works and can rethink the recirc system, which I'd still like to do but need to put in more design time.

The point of all this is to say you may need to install and then tweak your system to get it working the way you want. Try not to make the installation too permanent initially, and do some testing before burying line in the walls.

[ol trunt]

Rucker, when you work on your recirculation design include a thermocouple switch just after the water heater to control the burner. That will keep the water at +/- 2 degrees of your setting and "correct" for warmer water entering the heater as the water supply warms up. A dedicated hot water pump along with an accumulator will manage flow rate/pressure issues and you won't waste any water.
Jack

[Rucker]

Originally Posted by ol trunt

Rucker, when you work on your recirculation design include a thermocouple switch just after the water heater to control the burner. That will keep the water at +/- 2 degrees of your setting and "correct" for warmer water entering the heater as the water supply warms up. A dedicated hot water pump along with an accumulator will manage flow rate/pressure issues and you won't waste any water.
Jack

I think there are other things to take into account. Those instant water heaters are too clever by half.

I'm at the final stages of my build so I probably won't get back to the recirculation system for a bit. But I will post my experiment/experience to lay out what I've learned in more detail so I can see exactly the kind of advice you share.

In addition to the above, I'm pretty sure that I need to mix down the temperature of the water that is recirculating into the water heater to be slightly below its outlet temp. I also think I need to throttle the recirc pump so it recirculates but doesn't trigger the water heater to turn on.

[Dirtdoctor]

Do what suits your needs. I will never use pex again. Rodents go thru it as if it were candy floss. I’m out in the country and rodents in search of water is an issue.
I like copper, properly secured it will last a long time.

[TaliaDPerkins]

Originally Posted by Dirtdoctor

Rodents go thru it as if it were candy floss.

That sounds messy.


What standoffs/mounts do you use to keep copper from springing leaks with motion?

[Dirtdoctor]

Tom- the same poly mounts you use in a home. I have used the flex pvc with a threaded fittings to go from the tanks to the line. So there is some flex. But for everything else. I just use copper and properly secure it.