Questions tagged [mini-split]
A mini-split is a smaller HVAC unit with the blower and control unit inside a room, while the condenser unit sits outside. Use with any relevant tags (i.e. [electrical]). Use for questions about DIY installation of these unit.
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Convert a 240V dryer outlet to go through the exterior wall to an AC Disconnect?
I'm a DIY-er. I have a house built in 1972 with an unused 3-prong dryer outlet (I'm on natural gas now) that's on a 30 amp breaker. I want to remove the outlet and instead run wire from the box ...
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Mini Split with Central AC
Is it possible/efficient to have One mini split unit in the living room and remove all the ducts in that room to then have the central AC only cool bedrooms?
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Can a heat pump designed for mini-split system be used for central AC ductwork?
I am looking at replacing my old central AC unit with a heat pump one using existing ductwork. A contractor quoted me Fujitsu Airstage indoor unit AMUG48LMAS with outdoor unit AOUG48LMAS1. I checked ...
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Should I replace the HVAC or install a mini split in my garage?
I have a detached garage that was built with an HVAC system. Don’t think anything has been updated since the house was built 20 years ago. It was disclosed when I bought the house that it was ...
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For a HVAC condenser rated for minimum of 26Amp and max fuse 40 AMP what should be the disconnect sizing 30 or 60 AMPs?
For a HVAC mini split condenser rated for 240v and minimum of 26Amp and max fuse 40 AMP what should be the disconnect sizing 30 or 60 AMPs,
I am looking to hookup the mrcool 27k condenser which is ...
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Should I replace an old furnace with a mini split unit? [closed]
I have a very small house that is close to being 700 ft.². I live in the middle of Illinois some winters it gets really cold , many degrees below zero. Last winter I noticed my furnace having a bad ...
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What should I consider when deciding between a PTAC and a mini-split?
I have built a workshop addition to my garage and both will be insulated. I'm located in Central Indiana, so we get chilly winters (often down to 0°F) and hot, muggy summers (90°F and 80+% humidity).
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Should I use a 15 amp or 20 amp breaker for a mini split with max current at 13.0 Amps?
Installing a garage mini split with AC and heat. Running <25 ft of 12 gauge to disconnect and 10 gauge whip to condenser. Unit specs say rated for 8.7 Amp with max Amps in heat mode at 13.0 ...
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Installing a series of FS140 surge protectors to prevent mini split board burnups
I'm having some issues with my current electrical setup. I had an electrician install a 36k Eaton whole house surge protector about a year ago, and the hvac company installed a gree mini split. Since ...
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Do I need to vacuum-test the lines for a new mini-split?
Sanity check for installing a multi-zone mini-split system: I pressure test each zone individually. Then I vacuum each zone and release the refrigerant into that line set (assuming no leaks). Then ...
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Is there a category of ducted HVAC/IAQ parts but sized for what is typical for ductless systems? [closed]
There's old houses with extensive remodels that are in need of some kind of "zoned" help in interior air quality (or "IAQ", I'm not sure how common this acronym is just yet), ...
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Minisplit Install With Thin-Walled Lineset
I'm currently installing a multi-zone minisplit in my home. Unfortunately, I bought the cheapest linesets I could find. The 1/4" line has thinner walls and is very difficult to flare and torque ...
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Can I cover part of my mini-split cooling coil to remove more moisture?
At night during the summer, we run the kids room mini split with the door closed, and I've noticed the humidity gets really high (measured at > 70%). This surprised me, as I assumed the AC would be ...
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Mini split to cool one room and heat another
We live in a three story house, with our bedroom in the third story loft. On sunny days, it gets too warm up there, even with the windows open (not to mention the neighbor’s 4:00am rooster crowing). ...
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Couple of questions on the outside unit of a split heat and A/C installation
I have a Viessmann heat and A/C installation where a single large common outside unit located on the roof connects to split units on three separate floors.
First question:
There is a pair of copper ...
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Possible to install a mini-split condenser inside-ish?
Trying to install a multi-zone mini-split heat pump system in a small condo that does not have any accessible outdoor space* for condenser unit, however in the region jalousie windows are common and ...
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Configuring FHW heating system as a backup to minisplit
I installed a minisplit HVAC (well, HAC) system a few years ago. Very happy with it as housewide AC, mostly happy with it as heating (more efficient than the high-efficiency gas forced-hot-water ...
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Insulating outside minisplit lines
I need to insulate two outdoor minisplit lines. They are 3/8 and 1/4 inch copper lines - approximately 15 feet.
Edit: They came with insulation but after several years it is damaged and needs ...
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How do I wire a mini split that requires 208-230V with a 15A breaker, but came only with single pole wiring?
I am installing a Rovsun 12,000 BTU mini-split with heat pump. The voltage range is 208V-230V. The wiring for the unit consists of L1 Black hot wire, L2 White neutral wire, and the green ground wire. ...
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Can I use just split units for winter heating if I have both mini splits and hydronic base board heaters?
We're trying to go all-electric/solar and reduce reliance on fossil fuels. We currently have an 11 year old propane tankless combi-boiler that supplies hot water and also circulates water through a ...
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Multi-split Daikin air-conditioner errors and temperature issues
I have two indoor Daikin Perfera FTXM-R units hooked to a 2MXM-N9 outdoor unit. What I noticed is that the indoor unit closer to the outdoor unit (A) will start to report a very low temperature if I ...
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What data is available to support decisions about thermostat set point with mini split heat exchangers?
I have seen tons of references that say that the best way to run a mini split heat pump is to set it to target temperature and to let it maintain that temperature all day long, not differentiating ...
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Mini split beeping every 34 seconds
My Mitsubishi MSZ-FH09NA mini split head just started beeping. It beeps every 34 seconds whether on, off, or disconnected. This beep sounds slightly different than the on/off/function beep (quieter, a ...
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Heating is not working on DIY Dr Cool Mini Split
I recently installed a 3rd Gen 24k BTU DIY Dr Cool Mini Split Heat Pump, but I'm not able to get the heat working. The indoor unit does cool, but it doesn't doesn't do anything when I switch to heat ...
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Can my mini split disconnect be around corner of wall
I am looking at locations to install my mini split outdoor unit. One location would be: you are facing the outdoor unit, on the right of the unit, the wall ends about 12 inches away and turns back ...
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MRCool 24k BTU breaker size, wire gauge and disconnect box
I am looking to install a: MrCool E Star DIY 4th Gen 24k BTU Ductless Mini-Split Heat Pump Complete System 208-230V/60Hz
I reached out to MRCool support and they confirmed what I found through google ...
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Wiring mini split external and internal
I am looking to install one of the MRCool DIY mini split in my garage.
I currently have a 30amp 240v break and have run 10 gauge wire to a 20amp receptacle for my air compressor.
Can I just use some ...
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How to connect the refrigerant lines of the DIY Mr Cool Mini Split in Tight Space?
I want to mount the indoor unit of the DIY Mr Cool mini split on a wall inside the house that is a few inches across from a shed. Unfortunately, the proximity of the shed prevents me from accessing ...
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Should I cut out this repaired kink in a copper line set? (3/8")
I'm installing a mini-split, and in a moment of carelessness I slightly kinked the 3/8" copper line (the larger one). I repaired it using the 'wrench method' with some nylog to lubricate, and now ...
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Mini split for 14x15 room addition
We have a 14x15.5 family room addition on a slab. For summers we've used a window a/c. The room connects to the kitchen via a small 4.5 x 4.5 foyer. It has a doorway with the door removed.
The rest of ...
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Understanding heatflow, minisplit vs. open stairwell
Still getting used to the minisplit heat-pump HVAC (well, HAC) system I put in a few years ago, along with improving the house's insulation.
One of the differences I'm noticing from when I was heating ...
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Wiring for mini split sysytem
My mini split system call for a 12/3 wire on a 30amp circuit. I thought i had to use 10/3 wire on a 30amp circuit. Is it safe to use the 12/3 wire?
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Can I upgrade an existing breaker to add more load to a full panel?
I want to add three mini split systems to my house (two 18k, one 9k). I have a 100 amp panel that is full. I did a load calculation and with the additional mini splits I will be at 89 amps total (I ...
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Meaning of "standby" indicator on Mitsubishi mini-split
We live in western Washington state, and have an eleven year old Mitsubishi heat pump system consisting of:
PUMY-P36NHMU(R1) City Multi outdoor unit (service & technical manual)
PKFY-P18NHMU-E ...
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Thoroughness of residential mini-split plumbing tests
I'm installing a Bosch Climate 5000 series 3-zone mini split system in my house. This is my third mini-split installation (although I had an HVAC guy deal with the plumbing on the first one).
HVAC ...
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Do I need 5 separate disconnects for my 9k btu 5 zone mini split?
I’m installing a 5 zone 9k btu mini split and I’m not sure where to start with the wiring. Looked in the manual there’s a few different ways. I was hoping to use one box for my upstairs units (2) put ...
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Mini Split Leaking
I have 2 ductless Comfort Star mini-split units that were installed by a licensed contractor. One of them drips water from the air outflow. The contractor came out, took it apart, wet vacced out the ...
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Can I put more than one single-zone ductless mini split on a single branch circuit?
I’m planning to replace my old central forced air HVAC with mini split systems, but for a number of reasons, it will be more than a single multi-zone compressor. In that regard, am I required to have ...
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mini split line set run
I was looking to do a diy dual mini split unit one condenser 27k BTU 22 seer. Two heads 12 & 18k.
One head will be in the garage next to the electrical panel and the run for that is less than 10ft....
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Are there any ductless mini split systems that can use standard HVAC control wiring cables
I have a worn out 1990's quad mini-split system that use a separate class 2 (power limited) 24v control cable 18/5 to each indoor unit. The power for the indoor and outdoor units comes from 2 separate ...
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Watertight connector for Honeywell genesis 10753908
I have some Honeywell Genesis 10753908 cable that I need to connect to a mini split outdoor unit. The thing is outdoors, so it should be a wet and UV rated connector. Unfortunately, I have been ...
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Long refrigerator line in split AC
I'm considering a split AC/heat pump install for my house. However, one set of location (compressor on the ground, air outlet on second floor) would require running the refrigerant 15 vertical feet up,...
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Running line set for minisplit through soffit
I am installing MrCool DIY minisplits. I am wishing that I had just hired a professional, but unfortunately I'm too deep into this to change course at this point.
My question is whether it is okay for ...
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Can I Use 12g Wire off of 10g Wire for a Mini-Split?
I just removed an old mini-split from my son's house (hadn't worked for years). it was a 220v Fujitsu and I am putting in a 12k MrCool unit (110v).
I am planning on re-using the circuit breaker, which ...
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Mounting external component of split AC on hollow brick wall
I have a small split system (Philco Phs25ha4cpi). The external component weighs 25kg, and I have mounting brackets like these:
And a wall made from bricks like these:
My question is what kinds of ...
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Ductless mini-split AC with multiple indoor units for a home with small bedrooms?
Location: US, NYC. I want to improve the air conditioning setup for an apartment in a 2-family house. Current situation:
200 sq ft master bedroom, horrible old through-the-wall AC on a dedicated 20A ...
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Can I use different wire gauges in quick disconnect and from panel?
Quick disconnect kit came pre installed with 10 gauge wire.
The split AC unit calls for a 20 amp double pole (2 hots). So that sounds like 12 gauge.
I realize it’s probably okay to do 10 gauge for the ...
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What does a mni split AC do for thermostat?
I have a Hessaire mini split in a garage room. It's installed in the wall and has a remote. It acts like it has thermostat control (you can set the temp), but it is all over the place temperature ...
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Installing mini split system without wall core and running line set in attic
So the mini split I purchased calls for 3.5 inch hole to be cored from the handler unit to the outdoor compressor.
It’s always painful for me to see beautiful poured block walls destroyed, so my ...
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What kind of conduit do I need for my mini split AC line?
Running 240V for mini split through exterior wall in conduit from indoor unit to outdoor unit.
Cable supplied by mfg is SJOW 16/4 105c 251603 3/8" O.D.
Can use 3/4" non metalic flex conduit (...
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