Can someonr explain the idiosincracies I have observed in a peltier module?

In scrounging parts for the watermaker I cam across an interesting
surplus assembly. I was really after the 1 gpm flowmeter and stainless
needle valve but it came with a really strange device. One of those
things you just sense is to good to throw away. This thing is a pair of
hollow black anodized aluminum blocks about 4.25"x1.75"x1" with pipe
fittings on each end. They are bolted together with what appears to be
a couple of 1.5" square Peltier modules separating them.

Being a curious sort, I did the natural thing and took it apart to play
with the Peltier modules. First I put them on the VOM to check
resistance. They seems to float around between 19 and 22 ohms. Then I
wired it to a DC power supply and slowly cranked up the voltage. While
one side slowly got warm and the other cooler I could not get it higher
than 3 volts and the current never got above .25 amps. Changing
polarity did not make any difference.

This does not seem to fit any of my perception of the rules of
electricity. What is happening?

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
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