Best mini-spit heat pump?
- Thread starter MinnesotaEric
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lilyperch
Bronze Member
Check Gree, that's what I am going to use. They make them for Trane also.
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MinnesotaEric
Super Member
The 14/4 wire I got turned out to be too short. Ordered 20', got 15' and found out holding a wire that was 2' too short. Sigh.
For two hours I drove around and searched the area and nobody has 14/4 wire on a Saturday and so I punted and went boating.
Sunday, I hooked up the AC lines. The factory flares were roached, and so I made my own flares. Sadly, my made-in-China R410A manifold set stinks. When the valves are closed, they leak. Plan B was to get out a different manifold set. Anyway, I eventually was able to vacuum down to only 15" according to the China set and I found out the valves wouldn't close when I hooked up my nitrogen tank to pressure test at 400 psi.
Anyway, I'm now pressure testing overnight with a Yellow Jacket manifold set and a made-in-China ball valve. I think I have a tiny leak. Not sure yet.
One of my flares.
While waiting for the pressure test, I then made my own 10' whip from my outdoor switch box. I ran 10/4 out to my switch box but the Mitsubishi looks like it only wants the two hots and a ground and no common according to the instructions below. In the switch box I terminated the common on the same bar as ground since there wasn't a separate bar for common and that is what my household Square D 100 service box does as well. Out to the Mitsubishi I ran the common through the whip and terminated it anyway. Anybody know more about this as the schematic isn't clear to me as I thought the common is required if equipment takes one of the two hots and makes a 110 service internally out of one hot and a common.
I have the FH18 model.
Last edited:
aczlan
Good Morning
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- Tractor
- Kubota L3830GST, B7500HST, BX2660. Formerly: Case 480F LL, David Brown 880UE
That or they use a transformer to step the 240vac down to 24vac for the control voltage.
Aaron Z
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MinnesotaEric
Super Member
Okay, fair enough on the 240v straight up.
I talked to an HVAC guy today and learned something interesting. I introduced a little air while swapping from cheapest China manifold to better China manifold. Apparently that little bit of air is changing the pressure of my test depending on ambient air temperature. I set it can 400psi, and as the temperature dropped the pressure dropped 3psi. Yet I couldn't find a leak. I woke up this morning and I had dropped a total of 4psi. It warmed up all day and when I came home tonight I had gained 10psi. I think the HVAC guy knows what he is talking about.
Even so, I cannot vac and then cut off without another 1/4" male to 1/4" SAE ball valve so I may as well keep my manifold on and continue to monitor the pressure and get back to tractor stuff.
I talked to an HVAC guy today and learned something interesting. I introduced a little air while swapping from cheapest China manifold to better China manifold. Apparently that little bit of air is changing the pressure of my test depending on ambient air temperature. I set it can 400psi, and as the temperature dropped the pressure dropped 3psi. Yet I couldn't find a leak. I woke up this morning and I had dropped a total of 4psi. It warmed up all day and when I came home tonight I had gained 10psi. I think the HVAC guy knows what he is talking about.
Even so, I cannot vac and then cut off without another 1/4" male to 1/4" SAE ball valve so I may as well keep my manifold on and continue to monitor the pressure and get back to tractor stuff.
dadster4
Gold Member
Your test to see if the system is holding should be a micron-reading vacuum gauge. If the system has a leak, you will not be able to get down to 400 microns vacuum and hold it for about an hour. With the system pressurized to leak test, you don't really know if it is tight or ambient temp is messing with you. (30 years HVAC experience)
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MinnesotaEric
Super Member
The manifold is a three way. The only way to pass nitrogen is through the open center port and so I have a ball valve there to block. I need a second ball valve at the filler on the condenser so I can vacuum it down, cut off, and then flip my king valves open.
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MinnesotaEric
Super Member
I hear what you've said. I kind of wish I had purchased a Mastercool 4-way digital manifold but I do not have a micron gauge. So I'm on day three of holding 400 psi until I get another ball valve so I can pull vac and nitrogen charge three times in order to prep for the final vac and king valve flip.
If it leaks out, I'll get the Mastercool manifold, my digital scale and, a bottle of R410A, and fix the leak.
