Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: kgrover on October 16, 2023, 09:27:21 am

Title: Dual Mini split Install
Post by: kgrover on October 16, 2023, 09:27:21 am
Here's some pictures and information on my mini split install. Unit 1 is in the kitchen, unit 2 is in the bedroom. I removed cabinets to install the mini splits because I have a side asle and I kept hitting my head on the cabinets. The bedroom unit works great to keep the whole bedroom comfortable both in AC mode and in heat mode. The front unit in the kitchen takes a while to warm or cool the front area, but it does get there. The air flow just doesn't go in that direction. I think I need to add a small fan to move air around in the front a bit.

They both "soft start" because they are inverter drive compressors. so they ramp up speed and load over a few minutes. On full blast they pull about 1200 watts. This was heat mode because it's 45°F outside and the coach was cold. They don't sustain that for long and start to ramp the load back down. Once they have reached the temperature inside, they drop down to a few hundred watts to maintain the temperature.

Zokop Mini Split (https://www.ebay.com/itm/334873855614?_trkparms=amclksrc%3DITM%26aid%3D777008%26algo%3DPERSONAL.TOPIC%26ao%3D1%26asc%3D20230811123856%26meid%3Da6845b4e4a644fd4998fb359d286bf44%26pid%3D101770%26rk%3D1%26rkt%3D1%26itm%3D334873855614%26pmt%3D1%26noa%3D1%26pg%3D4375194%26algv%3DRecentlyViewedItemsV2&_trksid=p4375194.c101770.m146925&_trkparms=parentrq%3A38a1e03918b0ac6a06044ae4ffff3ef4%7Cpageci%3A46dfc0e5-6c26-11ee-8759-26953ae5ece9%7Ciid%3A1%7Cvlpname%3Avlp_homepage)

These are the ones I purchased, but I think any of them should be similar. My inverter didn't like trying to run both of them at full blast this morning off the batteries, but I just have 2 8D batteries in there. I also need to run the voltage sense wires to the battery still.

The bedroom unit outside component is mounted where the muffler used to be. The kitchen unit is mounted between 2 bays. I was thinking about putting a vent in the floor and some duct work for the exhaust air like the generator is, but the vents in the bay doors work well. I have 2 more vents to add but it seems to be working ok so far.

I can run the front one while driving with no issue. The alternator output is enough to run it and it keeps the front cool ish. I need to fix the dash AC still.
Ignore the wiring mess. I'm still working on the lighting.
Title: Re: Dual Mini split Install
Post by: Michelle on October 16, 2023, 09:55:14 am
How do you handle the condensation from the outside units?
Title: Re: Dual Mini split Install
Post by: Protech Racing on October 16, 2023, 10:37:44 am
I get very little or no water from the outside units.
The water comes from the hot moist air indoors
Title: Re: Dual Mini split Install
Post by: Michelle on October 16, 2023, 11:49:42 am
I'm thinking of during heat pump mode, especially during defrost cycle.  I wouldn't want that puddling in the basement compartment (photo 3 of kgrover's post above).
Title: Re: Dual Mini split Install
Post by: kgrover on October 16, 2023, 12:06:55 pm
I'm thinking of during heat pump mode, especially during defrost cycle.  I wouldn't want that puddling in the basement compartment (photo 3 of kgrover's post above).
I need to add a drain pan for that unit. I wasn't ready to need the heat just yet, the cold weather surprised me.
Title: Re: Dual Mini split Install
Post by: craneman on October 16, 2023, 12:08:52 pm
Isn't there a drain elbow on the bottom of the condenser? All the mini's I have installed had one.
Title: Re: Dual Mini split Install
Post by: kgrover on October 16, 2023, 01:02:10 pm
Isn't there a drain elbow on the bottom of the condenser? All the mini's I have installed had one.
There is, but I think it will be easier to just let it drain straight down through the floor instead of the elbow and then turning again to go down.
Title: Re: Dual Mini split Install
Post by: Bob & Sue on October 16, 2023, 01:03:21 pm
I can't get past the indoor plumbing part.  The DW is after me to do it but there's very little space in a 36 for it.
  The great thing is AC components innovation is moving fast so there's new stuff coming up constantly.
Title: Re: Dual Mini split Install
Post by: Protech Racing on October 16, 2023, 03:35:36 pm
I can't get past the indoor plumbing part.  The DW is after me to do it but there's very little space in a 36 for it.
  The great thing is AC components innovation is moving fast so there's new stuff coming up constantly.
I ran mine down behind the pas seat .
Covered with valence  .
Title: Re: Dual Mini split Install
Post by: "Irish" on October 16, 2023, 10:45:55 pm
Nice idea but it may not operate as intended. Air conditioning is all about heat transfer and the condenser does that getting rid of the heat. The current location of the condenser will make that impossible. It must be located in free air and according to all manufacturers minimum clearances which for mini split condensers (that I am familiar with) would be 5" to a wall and 20" to anything above. Having the condenser in the storage will not meet those requirements. This will make it difficult to achieve a temperature drop as desired, it will run continuously trying to dissipate the heat when the storage area becomes hot which will only take a few minutes.
You would need a ducted intake and exhaust system, or possibly some sort of flex piping allowing the condenser to stand outside when you are stationary.
I may be wrong, I am basing my comments on Mitsubishi and Bryant units that I see regularly, I could not find the installation manual for yours on line.
Hope it's working for you.
David
Title: Re: Dual Mini split Install
Post by: Bob & Sue on October 17, 2023, 12:30:33 am
David. I would agree completely and that does make total sense. 
  But....  Years ago we bought a duplex that someone had installed an AC ( window type ) in a wall that backed up to the garage.
  Said another way, the AC unit vented into the garage.  And I thought to myself that probably won't last long.  But it did.  It still works and hasn't caused and adverse conditions that I can see.  I expect they open the garage door when they're using it but I don't know for sure. 
  Bottom line, it'll probably work but surely work harder than it needs to.
Title: Re: Dual Mini split Install
Post by: Peter on October 17, 2023, 01:10:42 am
can anyone briefly explain what these mini splits are and what advantage they have in our FT coaches?
Title: Re: Dual Mini split Install
Post by: craneman on October 17, 2023, 11:12:56 am
The mini splits are much more efficient than our roof units. However on the unicoach models (bus style) installing them is almost impossible due to the sealed bottom. The condensers need air space and the air boxes need to drain condensate water. In the crane business I installed hundreds of split systems and one of the big failure rates came from putting newer larger condensers in the roof enclosures of the older smaller units. They failed prematurely due to high head pressure from lack of airflow. The GV's have underneath space that have enough airflow to solve that issue.
Title: Re: Dual Mini split Install
Post by: Protech Racing on October 17, 2023, 11:24:20 am
Also. They are almost silent .
Draw 1/2 the power. .
Title: Re: Dual Mini split Install
Post by: Bob & Sue on October 17, 2023, 01:32:26 pm
Also. They are almost silent .
Draw 1/2 the power. .
Plus, they heat as well as cool.
Title: Re: Dual Mini split Install
Post by: kgrover on October 17, 2023, 06:59:59 pm
Nice idea but it may not operate as intended. Air conditioning is all about heat transfer and the condenser does that getting rid of the heat. The current location of the condenser will make that impossible. It must be located in free air and according to all manufacturers minimum clearances which for mini split condensers (that I am familiar with) would be 5" to a wall and 20" to anything above. Having the condenser in the storage will not meet those requirements. This will make it difficult to achieve a temperature drop as desired, it will run continuously trying to dissipate the heat when the storage area becomes hot which will only take a few minutes.
You would need a ducted intake and exhaust system, or possibly some sort of flex piping allowing the condenser to stand outside when you are stationary.
I may be wrong, I am basing my comments on Mitsubishi and Bryant units that I see regularly, I could not find the installation manual for yours on line.
Hope it's working for you.
David
The rear unit is in free air, the front unit is between two bays using the bay wall to separate the two sides of the unit. When I was first testing it I left the bay doors open for air flow and now have the vents on the bay doors. I think I need 2 more vents, but I've lost the hot part of the summer to test that. Before I had the vents in. If I forgot to open the doors, I don't get much of a delta from the inside unit, it drops significantly when I remember to open the doors.  I need a good hot day to test the vents, but that might have to wait a bit.