Product Information > Product Reviews
Mini Split
lighthunter:
Recent storm proves ground pad is not what you want for harsh winter conditions. Off the ground and a doghouse of sorts would help with freezing rain. Ive had to pour hot water to melt ice about 5 times this winter. Not a tremendous amount of care but it could be avoided with install changes.
I plan to use a large plastic container to catch condensate next season. That way i can move it away from garage foundation and break ice from tub once a month.
Lowest current draw ive seen is around 3 amps (720w) of minimum modulation but then maybe the heatload wont allow lower as yet. Ive a feeling this 12k btu can only modulate from 720w to 1250w. Every machine is different but i personally think this one would be better off for efficiency wide open and then off for heat mode at least. Because of this issue i have decided on 9k unit for the next one so it can modulate lower down to match load, i understand this is especially important when used for cooling. That is if you want to realize stated efficiencys. It appears like a small modification to the indoor temp sensor could allow external manual control of power usage anywhere in modulation range.
lighthunter:
Hi all!
Very mild heating today. Outside temp only 10°F below the 61°F setpoint in garage.
Thought id check the minimum modulation current on the mini split. Room temp was extremely close to set point but it was not off, it was throwing a healthy supply of luke warm air. Supply volts 119.2-120.8- 1 volt for line loss. 239v @ 1.75A. = 418w. Ive no idea if it can go lower but ive never seen it this low.
This is a 12000btu unit. They make 9000 btu units that would be capable of modulating lower than this one, guessing they could hit 200w or less. Very nice. Two of the 3 arrays were off most of today. Kinda sad but good problem to have i guess.
Friday evening i noticed programmable relay control rebooting by itself every 20 sec or so and relays of all kinds switching back and forth. I killed power and fixed it this morning. Turned out to be a 48-12 buck converter that was unable to put out 250ma while rating is 10A. I had a spare, swapped it in and running in a few minutes. The culprit i suppose is this P75NF75 FET, 75V 80A driven by a UC3845A PWM controller. Will order a few tomorrow. Its been running several years so i cant complain. Nice thing is the control switched to grid without anyone even knowing there was an issue. (My sweetheart is very easy to get along with as long as her cell phone and the electricity are working properly...whew :P
noneyabussiness:
with the uc3845 IC , check the current sense resistor... had some corrosion on one once and it did a very similar thing .. worked fine for years then suddenly wouldn't supply even the tiniest current ( but voltage regulation unloaded was fine).. cleaned the corrosion off and sealed the board ... been fine since...
lighthunter:
Thanks, that makes sense, no corrosion to speak of but looks like board was never cleaned after assembly. Certainly could be some leakage. Will clean and test tomorrow, then let you know how it turned out.
We were talkin about meters today at work. I grabbed a Fluke 114 off the bench and tried to check internals of a SICK safety relay with it. It didnt even have a diode check function :o. Ok rant end.
When troubleshooting this buck converter, i used a uniT210e dc clamp meter, clamped the yellow wire and it read 250MA then i used probes to measure 10.xx volts on same wire. It sure made troubleshooting easy. I love fluke meters, it just frustrates me when they omit necessary stuff. I have a 189 in my tool bag but i think its gonna get replaced by a uniT. Not because of price but because it does it all, simple and lighter.
solarnewbee:
Hi LH, I have installed dozens and dozens of the Pioneer brand mini split. HVAC was my primary business before Covid Samsung and Mitsubishi when people wanted a familiar brand name. There are other brands with different names but the cases are the same they just slap on the name the customer wants when they order from china. I never had a call back for Pioneer labeled brand or any other brand from china but Samsung and Mitsubishi had many call backs for dead compressor, blown inverter board or bad indoor co from board. As a matter of fact I have 3 pioneer in boxes waiting to be installed when remodeling is done. Summer is almost here in the Philippines so projects need to be rounded out so we don’t run those amp hungry window units.
Adios
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