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It almost appears that you weren't at a high enough range on your meter. Sensors/ thermistors are typically in the KΩ range.

The flask would require some btus as well. The formula for anything is
BTU= lbs (per hour) x Δt x Specific Heat
So if you had 1 pound of water in a glass flask weighing 1 pound, you'd need 1 Btu...

Believe it or not the most educational stuff come from the dissection of vague questions. I think most people gain something when everyone throws in their two cents or past experiences, even if it...

Only one person has mentioned airflow so far though. There is no point in taking any of these measurements and using that formula (which doesn't have an air volume factor in it) if you can't...

Thanks, good read. Yeah I knew that, just tried to build off of been there's post. The only way we'd have pure liquid is if we subcooled the liquid to the evaporator saturation temperature prior to...

Agreed. Although I stated otherwise above.

Actually it really is. The refrigerant relies on the conditioned air to give it enough heat as much as the air relies on the refrigerant to "cool" it ( heat exchange). You will have liquid in the...

If you have a 2 pound capacity and 1 of it changes state it becomes a mixture of both throughout the circuit until additional heat can be absorbed to boil of the remaining half. When that occurs you...

So that being said, when we are measuring superheat, at the outlet of the evaporator, that 36 degree liquid would of have to become a 40 degree vapor giving a 4 degree SH and 100% vapor.

If no,...

It was, thank you.

So is it possible at that last portion, lets just say the outlet of the coil, to have 36 degree liquid with a vapor of 40 degrees?

Had to correct the above statement.

Good point, but I think what we see there is the warmer sub cooled liquid out of the condenser absorbing heat from the cooler, saturated liquid in the evaporator. The btus required for it to match...

So are you saying: A 63 psi R-22 coil with a saturation temperature of 36 degrees can have a mixture of 36 degrees liquid and 40 degrees vapor?

I'll have to start adding salt to my R-22 :)

Yes, direct contact. I assumed that was a given but then again we can go around and around on just about anything here :) Funny thing is that everyone, to a certain extent, is right in a way.

How many Btus is required to make10 lbs 32 degree ice to 40 degree water?

Before that 32 degree ice can gain sensible heat to go to 40 it MUST become water in its entirety. It must completely...

And again, that would be the ideal situation IF our pressures were dead on and at a true CONSTANT. Our thermometers were precise, and temperatures accurate.

And that's where I'm coming from. That's how the laws of physics and chemistry are set. We shoot for a "cushion" to play it safe due to all other variables in the field/ real world.

I'm sure you can, but I can only come up with all the wrong reasons. Like thermometer locations/ calibration, pressure fluctuations within the system, flow restrictions, etc.

The refrigerant in the evap coil is pretty much at saturation. It's not gaining heat to work its way up to it. If that was the case the liquid refrigerant would have to be well below the saturation...

Hurtinhvac, that was a fine visualization you gave me :)

Key word is CONSTANT. I agree with the fact that a uniform condition will not exist in a large mass, non the less one in motion, however in order to understand it you must take a uniform sample under...

Negative. Superheat is a sensible temperature measurement compared to a saturation temperature (estimated by an existing constant pressure in a heat exchanger). In order to have a sensible gain of a...

If I followed you correctly yes. But keep in mind that the steam/ vapor is still at the same temperature as the liquid, so the saturation temperature and existing temperature in the enclosure is the...

The confusion here is that there will be no transition of state if a heat exchanger (evaporator) is full of liquid. That is simply not the case. Assume 1 lb water (easier to relate to for people) is...