Playing around with an Empire Direct Vent space heater for my "lab"

Hello all from Michigan, good morning.

(I'm an engineer with a lifetime of working in test labs with equipment and other HVAC & controls experience)

I picked up this near new Empire space heater from a friend who was moving, didn't need it for his new place.

"EMPIRE DVC35 DIRECT VENT HEATER STANDING PILOT"

Before I decide the location and permanently install it (and cut a hole thru the back wall for venting, invest in a propane tank and cut a hole in the wall to bring that in from outside), I'm "bench testing" it secured to a wall as would be normal and with exhaust ducted out the window (with its normal exhaust piping).

Yes - if I permanently install it, will be permitted and inspected as per normal practice. Don't need to be told that.

It seems the discharge air temp outside is quite warm, a LOT of wasted heat. It's actually hotter than I can hold my hand against.

Seems a lot of waste heat. Is this just old school and efficiency that comes with that?

Has anyone who may be familiar with these ever seen what might be considered a "normal" exhaust air temp?

Thanks

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