On Board Water?

You're going to need 4 fittings to adapt the hose. Would you use brass or stainless fittings? Brass is economical but Stainless would keep the metal all similar but it gets expensive fast! Each fitting I looked at was $15 each...

I like the route Spencer used with the barbs.

Thanks!

Good catch! Didn't notice that.

 

Cool! Looks like a Teel. I was looking at the Flojet or Shurflow on Amazon. If I was to buy today I'd get the Flojet. But I haven't thoroughly researched this part yet...

 

Filtration and importance - http://rvseniormoments.com/projects/water-filtration/

 

I was looking at Duda Diesel's website and I found a nice description of how plate exchangers work, including a graphic and some useful text.

Here is an excerpt:

-Source



I searched the iterwebs and I found a discussion about the coolant flow of the Tacoma heater core here. (side note: I think the author of that thread used one of Tweeek's install photos!) One persons guess with a 5/8" heater hose was 3-4 GPM. Using that value, any of the 20 plate (or more) heat exchangers should be more than adequate and should not reduce PSI for the heater core / water pump /coolant system. Tweeek's and many others' personal experience more-or-less confirms this.

Without busting out some kind of PSI gauge pre and post heat exchanger install, it's really impossible to know for sure. However, it significantly puts my concerns to rest.

Lastly, Duda Diesel maintains an Internet forum and in this thread here, when asked for advice for on-board shower, they responded with this:

Filtration is kind of important.

Heat exchange reduced efficiency

 

Look what I just snagged. 12.50
http://www.ebay.com/itm/171372304698

 

Son of a bitch I paid close to 100 for mine...

 

Redid my bypass manifold. Didn't like the idea of galvanized crap that could corrode, and shrank the whole part by 2" or so.

For reference here's the first draft.



New manifold fits right next to the heater core intake

 

one of the reasons my projects take so much time. I'm patient, and like to wait for the right deal.

Did you get the Honeywell version? I was looking for the Honeywell with the BLACK knob and never could find one.

 

Moar.

 

I do remember reading somewhere where one person filled all the hoses and exchanger up BEFORE fitting it in there so they knew how much additional fluid was needed for the system. They they left it in there/ filled up the hoses and stuff as they were connecting everything. Was a mess from what I was reading and it pertained to a Helton style heater, but same concept. They had no issues and only had to add a little additionally to the system.

Try pulling the hoses and pouring fluid into them directly. in essence 'priming' the system.

 

That's what I'm thinking.

My ideas
The check valve will not crack below 5 PSI- so the giant air bubble in the system before that valve will just compress & effectively block the coolant circulation.
Or

Since I only added coolant to the reservoir and not to the radiator itself, the air bubble is stuck in the radiator & compressing, again, blocking / slowing down the circulation & cutting off the heat in the cab.
I'll pop the radiator cap off tomorrow & pray there's a huge air void in it that hadn't been able to pull from the reservoir yet.

I expect there to be a delay/ loss of effectiveness in the cabin heater when the heat exchange is turned on- but not a total loss and especially not a total loss os of cabin heat when there is no cold water pulling heat from the exchange...

 

Might want to eliminate the check valve all together. K.I.S.S........

 

http://www.my12voltstore.com/Eccote...ter_p/l5-fslash-pump-fslash-strain bundle.htm

 

Hmmm....
Went out & checked it this morning & noticed the coolant reservoir was 3" lower than I left it last night.... So there's a start.
Let it run & same thing- return line from heat exchange is still cold. Didn't have time to pull hoses or really mess with it so I'll see if there's anything in the heat exchange when I get home :0

 

Pulled the lines, primed with coolant, idled to regular temp on bypass mode- cab heater again works fine. Switched to shower mode-

20 min idling at 190 degrees & under 1,000 rpm, nothing. No cab heat no hot water through exchange.

Took a hot lap around the neighbourhood keeping it above 2,500 rpm and suddenly perfect cab heat and HOT heat exchange & hot water flowed through shower head once I pulled in the driveway.

Hot shower slowed to cold after 30 seconds or so while idling- again under 1,000 rpm.


Seems to me the check valve on the return (set at 5 PSI) is too high under idle conditions.

The point of this check valve: I can turn the 3 way valve in one direction (bypass) and have truck operate like a stock vehicle.
The other way, this check valve forces the hot water to go through my heat exchanger & heat the shower. In case of failure- broken exchanger or cut hose ETC
I turn ONE valve and it bypasses the exchange, making an idiot proof system that should function even in a failure.

Seems the only drawback is this system works only above 2,500 rpm.

So.... Now a hard decision. Keep it & accept the idle must be high to shower comfortably?
Or ditch it in place of a second ball valve and risk having a less than optimal not-so-idiot-proof system?

 

How would you go about raising the idle to 2,500 rpm?

 

Touché.

A rock?
But don't think even at 800 rpm idle it would circulate enough to give constant hot water.
Going into fairly uncharted water on this project it's tricky now

 

Ditch the check valve and see how it fairs.

 

Camera tripod to raise idle to 1050 Ditch the ball valve/check valve all together, or add a second ball valve. (I wouldn't bother, just be smart about your house routing, add a sleeve or split loom or something to any sharp edges)

You are very close, it's gunna work!

Standing beside the engine at 2500 won't be fun.

 

I would remove the bypass all together. With a 40 plate there should be virtually no pressure drop to worry about. Only variable I need to sort out is what long term effect does coolant have on stainless steel? Probably none but I don't know.

EDIT: After some casual internet searches, it appears that stainless steel is already used in plenty of automotive coolant applications- so I would feel very comfortable doing it now.