ShowerMiser - how difficult to install?

[NMWildcat]

Originally Posted by abehil

I'm guessing about how to install it, not how it works. Did they have to cut into a wall behind the shower to install yours?

We have a tub/shower with regular tub faucet. They drilled a hole on faucet shelf for the return line. Ran a line the length of the RV to the fresh tank since we have a tankless. Running the line to the non-pressure side of the pump introduced too much air for the tankless to work correctly, but would be fine fine for a tank w/h since it has an air space.
The miser valve attached to shower hose output of the tub faucet. When I'm home in a few days I can send pics if you would like.

[NMWildcat]

Ah, found a pic on my phone.

[Wes Tausend]

[QUOTE=abehil;2100467]I don't think running the hot line back down the cold line is going to work. I don't know anything about RV plumbing but seems likely to me that the cold line can't be forced backwards through the water pump... QUOTE]

Oh, sorry about that abehil. You are absolutely correct, it would be impossible to run water backwards through the water pump back to the fresh water (FW) tank because of the one-way pump valves.

That is not how the unique modification I mentioned works though. My suggestion is quite different from the ShowerMiser design to accomplish the same end.

It is supposed to work because the pressurized cold water shower supply is also hooked directly to the hot water tank (HWT) pressurized inlet supply. The circulation then occurs because of convection. The warm HWT water leaving the hot tank is lighter than the all the cold water in other pipes, so hot water rises like does a hot air balloon and ends up at the shower head.

In a full sized stick house with the hot water tank in the basement, this design feature is/was sometimes purposely set up as a permanent connection to upstairs plumbing fixtures without any extra valves (cross-over, bypass). The hot water then continuously rises to the hot water faucets, with heavier cooled-off water "falling" back down the cold water pipe back to the water heater inlet to be re-heated. Hot water is instant at the sinks and bath faucets almost as though one always left the hot water trickle down the drain.

The major downside to continuous flow is that extra heat energy is constantly lost in the pipes outside the insulated HWT. This wasteful process would not be so practical to leave run in an RV with limited propane. But it might be more practical if one used an RV hot-cold valve "bypass"(hot-cold cross-over) to stop continuous flow heat-loss and only opened it a few minutes prior to a shower. This would allow temporary convection circulation to allow warm water to rise to the shower. The up-side is that it would require no extra "buried" plumbing beyond the "miser-like" valve cross-over connection right behind the shower valves.

In other words, in this case the circulation would only occur between the shower and hot & cold hot water tank lines, not involving the freshwater tank at all. The normal ShowerMiser is quite different in that it always goes to non-pressurized water somewhere, the FW tank (preferred), or pump inlet for example. From what I've read, the pump inlet can be troublesome by introducing air if the tiniest leak occurs.

There is a good chance that the temporary convection flow would be too slow, especially if the RV HWT is not installed close to the RV floor level, or the shower faucet valve is not installed high enough above the HWT, as may be in a tub type shower.

But all of this potential convection-fail can be mitigated to obtain an instant hot shower by using a small 12v push-button pump right between the hot-cold shower supplies to quickly force the cooled hot-pipe water back down to the water heater using the cold supply pipe as the return. Even though such a pump might contain it's own backflow valve, one might still need a manual "miser-like" valve to prevent continuous accidental convection flow, wasting RV propane. I say "might" because a small spring load in the added pump ball valve might be enough by itself, to prevent the low spontaneous convection force in either direction.

Abehil, I realize this point is probably moot in your case. I posted back because a few people enjoy thinking about such projects. Only a very avid dedicated experimenter would probably actually try such a chancy modified arrangement.

Wes

[MilCop4523]

our 19 geopro 19fd has this feature and no one at the factory can understand why i cannot pump water from an overflowing FW tank with the FW pump.


I HAVE 2 WEEKS TO GET THIS IRONED OUT.

[NMWildcat]

Originally Posted by MilCop4523

our 19 geopro 19fd has this feature and no one at the factory can understand why i cannot pump water from an overflowing FW tank with the FW pump.


I HAVE 2 WEEKS TO GET THIS IRONED OUT.

I am failing to understand how the shower miser feature and your pump failure are associated. Maybe some more details or a separate thread?

[MilCop4523]

Originally Posted by NMWildcat

I am failing to understand how the shower miser feature and your pump failure are associated. Maybe some more details or a separate thread?

NMWildcat... according to the Rockwood techs they seem to think the miser is in the closed position and is somehow causing the water not to circulate by using the FW pump.
City water it works fine.

FW pump (off city water supply) takes the water from the HW tank and depletes it through the open tap. will not pick up water from tank or shut off when turned on.

Just glad I had the HW tank turned off when we were attempting to figure this out.

[NMWildcat]

Ah, it wouldn't surprise me if they plumbed it incorrectly. Hopefully you can see enough of the pex to determine where all the pipes go and how it's connected. It truly is a wonderful system (shower miser) when plumbed correctly. Hope they get it figured out for you soon!

[Wes Tausend]

Originally Posted by MilCop4523

NMWildcat... according to the Rockwood techs they seem to think the miser is in the closed position and is somehow causing the water not to circulate by using the FW pump.
City water it works fine.

FW pump (off city water supply) takes the water from the HW tank and depletes it through the open tap. will not pick up water from tank or shut off when turned on.

Just glad I had the HW tank turned off when we were attempting to figure this out.

Milcop,


The ShowerMiser is supposed to pump hot water back to the FW tank only when the ShowMiser diverter is set to do so. If the factory mixed up attaching the shower hot water pipe with the return line, which are probably in close proximity near the shower head, the FW pump would just continuously pump hot water back to the FW tank and never build up significant pressure to anywhere. It might dribble out of other faucets, but that's about all. Good luck and I hope you have a great week-end.

Wes

[abehil]

Originally Posted by NMWildcat

We have a tub/shower with regular tub faucet. They drilled a hole on faucet shelf for the return line. Ran a line the length of the RV to the fresh tank since we have a tankless. Running the line to the non-pressure side of the pump introduced too much air for the tankless to work correctly, but would be fine fine for a tank w/h since it has an air space.
The miser valve attached to shower hose output of the tub faucet. When I'm home in a few days I can send pics if you would like.

Thank you for the details. So your trailer has a tub with a ledge? And the ledge would allow someone to reach up from underneath the trailer?


Many have a shower with the handles/knobs installed in the wall of the shower, sometimes near the bottom but mostly about half way up the wall.

To secure the Showermiser to the wall, you have to drill a hole for the return line and one end of the showermiser goes through the hole. On the back side, you screw a flange nut on that part of the showermiser to secure it to the shower wall.

That means somehow getting behind the wall to screw the flange onto the showermiser. That is the reason I keep asking about HOW to get behind the wall to do that.

I can only think of a very few ways to get behind the shower wall. And remember, this if for someone doing a DIY install (who isn't familiar with RV construction).


1. Somehow pop the shower wall loose and reach around.
2. Cut into the wall behind the shower. This isn't possible on the trailer I want because the shower wall faces the outer wall and I'm not cutting through the outer wall.
3. Maybe the mounting plate where the shower knobs are mounted can come off and maybe there is a big enough opening to get hand or at least fingers back there to put the flange on. In residential tub/shower surrounds there is usually a big round ring about 6 to 8 inches in diameter and can often get behind the wall a little and then the plate covers up the whole area. But I don't know what is behind the RV shower knob mounting plate so it's a mystery at the moment as to whether this would work.


And the return water line has to be connected through the flange nut, or maybe after the flange nut is on and tightened. Maybe it can be passed through the flange nut and pulled out through the hole in the shower wall and secured to the showermiser and then poke the showermiser back through the hole - but then tighten the flange nut.



So if there is any hope then this one part of the installation has to be figured out - hopefully without cutting into walls.

[ependydad]

A couple of videos imply that you need access to the rear of the shower:

https://www.youtube.com/watch?v=oQqHdvP28jI

https://www.youtube.com/watch?v=rRCuBPG5aEU

The only thing I'm curious about is if removing the shower faucet itself is if you'd have enough room to reach in and handle the shower miser blindly.

[NMWildcat]

In every RV I have had, there was always an access to the shower,sink,tub faucets from below. Usually via an outside cubby. Sometimes a wall access panel. They have to have access at the factory to install the faucets and pex. So I'm thinking you should have access somewhere. Might not be easy or large, but you should be able to reach them.

[abehil]

Originally Posted by NMWildcat

In every RV I have had, there was always an access to the shower,sink,tub faucets from below. Usually via an outside cubby. Sometimes a wall access panel. They have to have access at the factory to install the faucets and pex. So I'm thinking you should have access somewhere. Might not be easy or large, but you should be able to reach them.

Specifically I'm interested in HOW when the shower is in the corner of the back wall of the trailer or just backs up to an exterior wall. Hard to reach up 5 feet from under the trailer to a set of knobs where the cavity is 2 inches deep.


Has anyone taken a shower wall off or pulled it away? Can it be done with out causing damage?

[ependydad]

Originally Posted by NMWildcat

In every RV I have had, there was always an access to the shower,sink,tub faucets from below. Usually via an outside cubby. Sometimes a wall access panel. They have to have access at the factory to install the faucets and pex. So I'm thinking you should have access somewhere. Might not be easy or large, but you should be able to reach them.

I've only had 2 campers now and the back of the shower was NOT accessible in either.

[NMWildcat]

Originally Posted by ependydad

I've only had 2 campers now and the back of the shower was NOT accessible in either.

Hmmm. The first thing I do in every RV is replace all the fixtures. Shower included. So in your case, they must of assembled the shower faucet and pex on the enclosure, and then installed the enclosure? So that would mean you would have to remove the enclosure, which is what the OP is asking. Guess I'm lucky, always had access w/o having to do that.