Heater Core Question for On Board Shower

Hello, I am putting together parts to install a onboard hotwater shower using a heat exchanger. I will tap into the heater core hot water to go through the heat exchanger. I have 2 questions:

1. Which line is the inlet and which is the return line from the heater core? I see the two coolant hoses going into the firewall on the drivers side and want to tap into the return line so as not to effect the efficiency of the internal heater.

2. Does hot water flow to the heat exchanger all the time, or only when the heater is on? I know older vehicles used to flow only when the heater was on, but I have heard that many newer vehicles flow continuously regardless.

 

Cheaper then this? http://www.walmart.com/ip/Zodi-Instant-Water-Heater-and-Hot-Shower/4698021

 

To answer #2, it flows all the time.

The people I know who used the Helton and similar systems on the Tacoma have reported that they have to recirculate water in a bucket to get it to the desired temp.

Sounds more trouble than its worth to me and it's not something I would want do, but to each his own.

OP, have you tried posting over at www.expeditionportal.com/forum

EDIT: A simple search here, yielded someone who cut up his hoses here:

 

I dont really want this thread to be a debate on what setup is better, but I want to accomplish a couple things with the heat exchanger

1 carry less crap, all I will need is 2 hoses.
2 a 12v pump piuts out way more pressure than the zodi
3 no need to carry extra propane

 

Thanks for the reply. I am going to try and use a more efficient plate heat exchanger than the helton. If the engine is operating around 190 degreea I believe the temp should be sufficient. I know many people have had good results with the helton on other vehicles, plate exchangers are a fraction of tbe cost.

The pictures you posted are very helpful, but from a first gen. I need to know which line is the return from the heater core.

Thanks for answering #2. That is the answer I was hoping for.

 

I actually don't know about the 1st gens but the 2nd gens circulate all the time, so I've heard.

 

I'm not too sure about which line is in & out, I ran mine from another coolant line coming off the engine near the oil filter.

Here's my original post:

Haven't got a picture of the direct engine shot. But I can get one if you like.

But I've re-did the system to bypass the heat ex-changer when not needed. And have the pump inlet take water directly then push through the heat ex-changer.

 

Yes, this is what I am looking for. Ill have a look for the other coolant line by the oil filter.

What heat exchanger did you use? How are you finding water temp & pressure?

 

I'll try to get a picture of my setup tomorrow. I'm using a 10 plate flat style ex-changer. Pressure seems to be okay for now, but my pump is not a 100% duty cycle so I try not to use it for too long. Temp I'm still playing around with trying to figure out how long I need the truck on for. I tested it once right after driving at full operating temp, and the water was perfect.

 

Hey, any update on this? Get your temp figured out or a picture of the setup? Cheers!

 

Hey, will get the picture tomorrow. Haven't figured out the heat yet. It's strange, seems sometimes I don't need much and other times I need to keep the truck on.

 

Im going to bump this again because I am still really trying to find out which is the inlet and which is the outlet to the heater core.

 

What came of this?

 

V6 with the towing package has an oil cooler in the filter base.
V6 without towing package probably has both ports plugged.

 

I ended up tapping into the heater core as I allready had the right sized fittings. Used the shower this weekend, it works fantastic, its hot enough to burn at the hottest setting, but you can dial it to whatever temp you want with the thermostatic mixing valve. Drop a hose in the lake and have endless hot water. Something invigorating about a hot naked shower outdoors haha. Make a hot tub? Lol... I did find I have to raise the idle to about 1100 or 1200 to get the hot coolant circulating properly.

 

Hard to see, but the pump is mounted below the mixing manifold

 

How do you prime your hose for the draw of water? a simple submersion of the whole hose in water then screw it into the truck?

 

Oh, and how many PLATEs did you get? Looks almost like a 20 or 30 stack.

 

The pump self primes. I have a flojet pump that will prime upto 9 vertical feet. I connect a 20ft hose to a connection mouted on the bottom of my bumper and drop the other end in the lake or a water container and the pump does the rest.

Its a 20 plate, 12" x 3". Admittedly overkill, but I read that some people attempting this on tacomas were having to recirculate the heated water and having poor results. I wanted something very efficient. Its the legnth of the heat exchanger that makes it more efficient, not the amount of plates. More plates reduces pressure drop.

In reterospect, a smaller exchanger would probably work... I am thinking that poor performance people have seem with the small exchangers and tacomas has to do with the idle speed. Even with my large exchanger I have to raise the idle to aboht 1100 to get the engine to circulate the hot coolant, then the water is litterally scortching hot coming out of the exchanger. YMMV.....