Thanks AC_Hacker and jeff5may for this great info.
I know the feeling of working nonstop and no time for hobbies... with house remodel and my day job, I am pretty much working non-stop 16 hour days. Only time I have to play is when I put something else on hold...
The compressor is actually not a 270v hotel unit but from a large residential window unit that the fan motor went out on. I haven't been using the hotel unit compressors for anything, right now I have 18 of them, different makes and models but all around 12k btu. Each unit yields about 1.5lbs of r22. Hate to say it but they will all probably end up at the scrap yard.
To be completely honest, I don't know what the "bell shaped thing" is called. Maybe an AEV (see picture)? It came from an older hotel unit. The label has completely faded to white because it sat in the sun for a year in my backyard before I reclaimed the refrigerant and started stealing its parts. This was the only unit with such a device and when I tested it the unit, I noticed how it kept the low pressure right around 57 psi. Turn it out and the pressure would drop to 50 psi or less and turn it in and it would raise to 60+ psi (or vice versa…can’t remember? ). I kind of took a chance at using it because I didn't want to only use CAP tube without knowing how this unit was react and didn't want spend a bunch of money on this thing until I proven it can work.
Here is what I noticed at first with it being with water HX instead of air. If the HIGH side HX water is "cold", below 60 degrees F or gauge reads less than 100 psi, the low side will drop below 50 psi. At first I shut the unit down when this happened because I didn't want to break my new toy, and even though the HX looks cool, I don't really need a $135 paper weight. After gathering my thought, I plugged it back in and adjusted the bell shaped valve so the LOW side was just above 57 psi. It wasn't freezing at this point because the dew droplets on the copper were not frozen. As the high HX temp rises the CAP tube is forced to send more refrigerant and bell shaped valve seems to do less work. At around 250 psi on the High side the low side has risen to over 60 psi. I see the danfoss units use an electronic expansion valve (see picture)
I need to get my raspberry pi setup to get some real numbers here. So I can determine what is actually going on.
There also seems to be a discrepancy with the numbers the turbonics people have on the PDF and the temps I’m seeing.
They say: at 45f in water temp. Exiting air temp should be 52.9f. They also don’t list entering air temp. There unit has 4 4” duct ports, I modified mine.
I get: at 34f in water temp. Exiting air temp is around 65f. My entering air temp is around 75f and my return water temp is 50f. I modified my unit giving it 2 6” duct ports instead of the 4 4”. Although it seems to be able to cool the 2 rooms it is connected to, it takes quite a while to do so… and that’s not even close to the numbers they have.
I was planning on running my second unit off the same heat pump which I think I can because the low side HX has no problem keeping up with the 1. The problem will be, what to do with all the heat?
I’ll do some more testing tonight after work. It’s supposed to be 96f today.
as far as reversing valves go. I have 5 of them, I was thinking, could use 2 of them, swapping all 4 ports on the HXers. Wouldn't need a fancy reversing expansion valve either. Just a thought, got all these parts and I'm dying to use them!!!
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