850 watt tank style coolant heater - installed in the Blackfly
 

(Originally written: Feb. 27/07)

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I usually (selfishly) don't like to publicize auctions I'm interested in, but this one has 10 units available, so if anyone else is looking:

http://cgi.ebay.ca/ws/eBayISAPI.dll?...DME:L:RTQ:CA:1

This is the tank style heater that goes inline between the water pump and heater core. It uses convective circulation.

850 watts is a lot (my current external bolt-on unit is 300w). I'm going to try to win one of these.

March 12:

My nuclear powered 800w block heater arrived today.

Havent really looked at it yet.

First thing to determine will be whether it'll fit the size heater hose already on the car. If not ?? there must be some kind of step-down adapter I could use.

April 18:

Coolant heater installed.

I'm not really happy with the installation - due to a lack of space, and the positioning options (or lack thereof), I had to add an elbows on each end of the tank to prevent the heater hoses from kinking to get them to where the tank is. So I ended up using way more hose clamps and little "splice" sections of hose between the various parts.

And I couldn't actually find elbows - I got "tee"s instead, and epoxied one of the "extra" ends closed.

Mickey mouse, overall.

But I drove it around and it doesn't appear to be leaking. Haven't done the critical test of plugging it in yet (needed to get the air out of the system first).

First test will be tomorrow AM. Should be interesting. Hopefully not TOO interesting.

Well, after a promising start, I'm not sure the thing is working.

I plugged it in, and could hear & feel the coolant sizzling & bubbling in the tank, and within 10 minutes the coolant temp was up 20* F above "cold". Woohoo!.

But 10 min later, it was only up another 5 F. 10 after that it was down a couple. :confused:

Not sure what happened (didn't have time to troubleshoot this morning).

Also I can't be completely certain that my cooling system is set up to do convective circulation through the coolant pump return line. Maybe it only works if the pump is turning.

April 22: So, I did another test. After topping up the coolant (I do believe there was an air pocket last time).

Plugged in the EBH:

73F - start
76F - 10 min
83F - 20 min (hose to tank feels warm - suggests convective loop flow)
85F - 30 min (all hoses from tank hot, block warm)
89F - 40 min (hoses from tank very hot, water pump warm)

So I'm thinking there's a lot of stored heat in the coolant, but it's not flowing to the sensor as much as I'd like. A plumbing issue, perhaps?

I figure: best way to know for sure is to start the car, and get the coolant flowing past the sensor.

121F - 30 seconds after starting (@ idle)
127F - 60 seconds after starting (@ idle)

Nice. I never saw a 50F increase from the 350W external heater (+40F was about as much as it would add), after 1.5 - 2 hrs.

+50F in 40 mins is quite nice. I'll probably do another test again...