[kittydog42]

You should consider pumping into the heater core (as opposed to sucking out of it), or else you probably will have a rough time getting the air out of the system.

[david85]

Originally Posted by JRP3

Here is the pump I will be using:
http://www.adventurerv.net/shurflo-n...92iec6b73l3um1
Plumbed after the heater core just before the heater the water should be pretty well cooled off before it enters the pump.
I'm using the Katz heater
http://www.amazon.com/gp/product/B000BQUUR6
Sitting in a cold garage plugged into AC power it puts out a lot of heat with the blower running, even without the pump.

Thats something else I was wondering about!!!! I'm glad you mentioned that.

If the heater is right next to the heater core, I would expect a decent amount of thermal conductivity through the fluid without even havint to circulate anything.

I'm even toying with the idea of installing the complete heating system inside the passenger compartment to eliminate any possibility of waste heat outside the car.

How far from the heater core is your fluid heater?

Have you measured what temperature you are getting at the vents?

That pump is something I might be able to get locally, I see them in fliers on occasion. Typically marketed for pesticide sprayers so corrosion resistance is not an issue. I just feel its a bit of an overkill that will add to battery drain.

Oh, and the electric BMW I linked to earlier is using 144V nominal, so on a full charge, you get more than 150V, so 10 amps @ 150VDC = 1500 watts.

kittydog42

I'm planning to have the pump installed below the top of the heater core. That eliminates any issues related to priming, since the impeller chamber will always be full of water. Ideally, the heater, pump and heater core will all sit about at the same level.

[JRP3]

Originally Posted by david85

I'm even toying with the idea of installing the complete heating system inside the passenger compartment to eliminate any possibility of waste heat outside the car.

I wrapped my heater and hoses with pipe insulation.

How far from the heater core is your fluid heater?

I have about 12 inches of hose between the heater and heater core. Have not measured temperature.

That pump is something I might be able to get locally, I see them in fliers on occasion. Typically marketed for pesticide sprayers so corrosion resistance is not an issue. I just feel its a bit of an overkill that will add to battery drain.

The pump is a low pressure low flow pump, I wouldn't think it would work in a sprayer application. It draws less than 2 amps at low pressure. More details:
http://store.solar-electric.com/100-00-21.html

kittydog42

I'm planning to have the pump installed below the top of the heater core. That eliminates any issues related to priming, since the impeller chamber will always be full of water. Ideally, the heater, pump and heater core will all sit about at the same level.

You will need to bleed air out of the system somehow. I did it crudely by overfilling it a few times while holding the connections above the rest of the system. I may put in a pressure relief valve or a remote radiator cap setup. http://www.siliconeintakes.com/produ...oducts_id=1064

[Woodsmith]

Originally Posted by david85

If the heater is right next to the heater core, I would expect a decent amount of thermal conductivity through the fluid without even havint to circulate anything.

I'm even toying with the idea of installing the complete heating system inside the passenger compartment to eliminate any possibility of waste heat outside the car.

If you are really keen to run without a fluid pump then it would be best to site the heater as low as possible with a section of pipe going straight up, That would help get the thermosyphon working. The system needs to be a vertical layout rather then a horizontal one. Also large bore pipe helps.

Fitting it into the passenger footwell would be a good way to do this. Maybe even running large bore pipe along the tunnel and around the inner sills and across the top of the dash would work with a thermosyphon system. The heater would be under the dash and the water would rise to the dash and then slowly work its way around the sills and back along the tunnel for each side of the car.

It would be like a Victorian hot house system.

[mill]

Originally Posted by david85

I'm holding out for something brushless like this:

http://cgi.ebay.ca/12V-WATER-CIRCULA...item4ceb7ad6c4

Not sure yet what flow rates are needed.

You figure 6.5LPM would be enough?

http://cgi.ebay.ca/NEW-Mini-DC-12V-H...item4149b9e410

good luck getting the air out of a heater core with no pump, especially since its the highest thing in a thermosyphon. I would use the pump from the top link, that's a new style vw/audi coolant pump and they are indestructible so far, we haven't seen one fail at the shop. the other vw pump shown on this thread somewhere is known for leaking. in real life they only pull about .6 amps and you cant really even hear them when they run. I'll check the shop tomorrow and see if I can scrounge one up if your interested.

[JRP3]

Don't know about David's setup but it was pretty easy for me to lift the rubber hoses up higher than the heater core in mine to get the air out.

[mill]

Originally Posted by JRP3

Don't know about David's setup but it was pretty easy for me to lift the rubber hoses up higher than the heater core in mine to get the air out.

not saying it would not work, I am not familiar with the saturn setup either, I just think a having a pump would be a good sure fire way to go, especially in his climate.

[kittydog42]

I don't have a problem when I pump into the heater core. Every time I have tried to suck out of it, however, I have had to punt and reverse the lines. That is just my experience, though, it sounds as if others have made it work both ways.

[JRP3]

Originally Posted by kittydog42

I don't have a problem when I pump into the heater core. Every time I have tried to suck out of it, however, I have had to punt and reverse the lines. That is just my experience, though, it sounds as if others have made it work both ways.

I'm not sure of the difference in a closed system. It's essentially a circle so the pump is always both pushing and pulling.

[Woodsmith]

The impellor in the pump may cavitate and produce bubbles so it would be better to put the pump where the bubbles can quickly escape to a high point for bleeding off.