This heat wave and mini splits

[GlennWest]

This is just infirmation. We are in Port Arthur TX and yesterday was low 90s with heat index 105. We had people leave this park we in to go to a covered rv park. Hostes was telling me they could not get under 80 degrees in their 50 amp 2 ac units. It has been like this for days. We are at 70 degrees in our Teton. Mama can wash and dry clothes in the heat of day and no affects on temperature inside. Now I know our Teton is insulated better than most but I remember mama would not dry clothes except at night in this weather. Also she would set  termostat in the 60s and get it cold as she could early morning to keep it bearable in heat of day. And that was 2 15k dometics. And mama tells me over and over "Thank you". Live is good with mni splits. 

[Twotoes]

I’m in Omaha NE and it’s knocking on 90 degrees everyday with night humidity. I have all 3 A/C going and am keeping the interior at a comfortable 70 degrees. At night I keep it at 74. My Itasca has great insulation. 

[GlennWest]

Reckon you do with 3 acs. 

[Daveh]

We were not planning on being in Arizona this summer but due the Covid we have stayed in place. I have a 12000 btu 120 volt minisplit. I assume it is not at maximum efficiency as  I was unable to complete the install as my line set ended up two feet short for my desired location and I was forced to put the outdoor unit and the lineset in a position that is fully exposed to the Arizona sun. I hope to complete the install this week but that means taking the AC offline for a few hours and it is really hot. We have had quite a few days where the actual temperature is between 103 and 105.  We are at about 3700 feet elevation so most of the highs are in the high 90's. This minisplit is soooo quiet and easily outperfroms the Dometic 15k.  Our unit will stay at 75 or below unless the temp gets over 95. The it will start creeping up and if it gets to 79, we generally put on the Dometic and the both of them together handle things very easily. We have a 39 foot Arctic Fox fifth wheel with 3 slideouts.  I am thinking of getting rid of the Dometic on the roof to use the space for Solar. In our normal fullltiming, which avoids temperature extremes, we would never use the Dometic. Oh, we are in direct sunlight. As soon as the sun goers down the minisplit will take the unit all the way down to 62.

[rpsinc]

Perhaps you can get a low priced EZ up from say Harbor Freight to use as a shade for the outdoor unit?  Might buy some time till better weather to complete your install.

[Will B.]

These things, when they are ductless....where does the water go they pull out of the humidity?

[GlennWest]

Drain lines

[Alie&Jim's Carrilite]

We left south of Chandler Az last Sunday with temps running 110-112.  Low humidity at 4-7%, but 14hrs a day of sunshine creates a lot of heat gain.  We had our 3 units set at 76* during the day and it was comfortable inside (no humidity).  No reflectic stuff on the windows.

[GlennWest]

I really want to go to AZ and exsperience that. Everyone tells me though that the low humidity makes it bearable. Half the battle is removing humidity when cooling. 

 

[noteven]

I sketched an idea out where a RV could have a deployable shade cloth over the whole unit - stores lengthways down the middle and is deployed out over each side by awning arm kinda mechanism... but this would require auxilliary solar somehow...

And then I thought cover the whole roof with a solar shade and have solar awnings on both sides...

kinda like:

Everlanders - solar panels and mini split

[GlennWest]

Watched his videos. That's very intriging. I can fit 4k on roof. Doing this I could fit 8k on roof. Just don't think it will be necessary though. 

[packnrat]

i have been reading a bit about this called “mini split”.

question? can it run on 12 volts dc? or is ac required, thus need to run a generator just keep cool. yes i only boon dock. have only paid for a spot once. in all my years, ( had to be in reno for something one week).

[GlennWest]

They are 120v, 240v and 48v DC. The 48v are twice the cost but Seer high.

[Daveh]

"I really want to go to AZ and experience that. Everyone tells me though that the low humidity makes it bearable. Half the battle is removing humidity when cooling. "

Still feels hot but not that suffocating clammy feeling and your not drenched in sweat when doing things outside. Much more tolerable than the Michigan summer heat I am used too but get me up around 95 or above and I am in the AC. Hot is hot.

 

 

[packnrat]

i would say avoid arz all year.

i once spent Christmas there. was too hot to be outside on Christmas day.

but then i cook at 80F.

[GlennWest]

In been in south Texas and Louisiana far too long. 

[Alie&Jim's Carrilite]

13 hours ago, GlennWest said:

I really want to go to AZ and exsperience that. Everyone tells me though that the low humidity makes it bearable. Half the battle is removing humidity when cooling. 

 

 

2 hours ago, Daveh said:

"I really want to go to AZ and experience that. Everyone tells me though that the low humidity makes it bearable. Half the battle is removing humidity when cooling. "

Still feels hot but not that suffocating clammy feeling and your not drenched in sweat when doing things outside. Much more tolerable than the Michigan summer heat I am used too but get me up around 95 or above and I am in the AC. Hot is hot.

 

 

Best way I can describe the Arizona heat is to turn on your wife's hair dryer on high heat and aim it at your face- 5-6 inches away while standing in front of your oven with the door open while its on broil.... 

When its breezy it hot air, low to no humidity means the air temp can be higher to be comfortable, but the evaporation rate is crazy.  Working outside in the afternoon means drinking 8oz of water every 15-20 minutes.... and you're not sweating.

[folivier]

Basically in the dry heat when you sweat it evaporates so quickly that it can have a cooling effect unlike in high humidity areas where the sweat just accumulates on your body and doesn't evaporate.  That can have a somewhat insulating effect and not cool you off.

So if you're in the very low humidity and high heat in Arizona if you're in the shade with a breeze you can be comfortable at temps at or over 100ºF.  Try that in south Louisiana at 90% humidity and 95º!

Just remember to stay hydrated!  BTW we visited friends in July west of Phoenix one year and never will do that again.  Hit 114º a couple days.  That my friends is HOT!

[lappir]

I'm not in Arizona for the summer heat wave but in SE Missouri. There certainly is humidity in addition to the heat. I have a single ODU (Outdoor unit) and two IDU's (Indoor units). I don't have a lot of windows, but I do have a few and certainly would have less if I were to build another trailer. Actually I would probably more aggressively investigate the possibility of having "Horse Trailer" like windows over a conventional window. You know the kind you see on the horse trailers on the road that are hanging down and open when the horses are being transported in the warm weather and closed when it's cold out. I'd turn them upside down and only use them when parked as a awning  and keep them closed while on the road or during inclement weather protecting my glass. Potentially could do this as a retrofit someday I guess. 

Now back to the Mini Split.  I have finally figured out how to use both of my IDU's and not have it wake me up in the middle of the night. I have to keep the larger unit (18000 btu) in the garage end of my home set at a lower temperature than the smaller (9000 btu) unit in my bed/living room.  If I try to put the living area unit at a lower temperature I am bothered about a very high pitched squeal that seemed to come at 3AM when I first started using the Mini Split system. After a full month here in Missouri I'm happy to say my sleep has not been disturbed by the Mini Split. 

Depending on the location my electric bill has ranged from $18 per month to $40. With the highest I was also allowing electricity to heat my water. At the lowest I would use my gas as an instant heat. It only takes 5 minutes for me to be able to take a comfortable shower after flipping the switch to light the burner. When it's on electric I just leave it on. I haven't tried to find out how long it would take with just turning the electric portion on. On arrival to a new spot I sometimes use both, not for any good reason it seems today. 

I started this message a few days ago and thought it was lost. Came back to redo it and found the prior written part still there. Will have to remember that. 

 

Rod

 

[Randyretired]

I just installed a mini split on our Teton.  We are in the Colorado high country but only about 7200'.  In this heat spell the afternoon temps are in the middle to upper 80's.  We are boondocking.  The 12000 btu mini split easily keeps us cool and 2000 watts of solar means the batteries are never challenged.  Of course the high country cools off quickly when the sun goes down so we can shut off the AC.  Still I am impressed with this mini split and it is very quiet.  

[GlennWest]

Congradulations Randy. We thoughly enjoy ours. You can never get across how nice these are until one tries it.

[Randyretired]

29 minutes ago, GlennWest said:

Congradulations Randy. We thoughly enjoy ours. You can never get across how nice these are until one tries it.

That is true Glenn!  When I move more than a few feet away from the inside unit I can't tell if it is on it is so quiet.  Thanks for your advice as you and others convinced me to install this mini split.  The heating function also works well.

[remoandiris]

Is it practical to replace a roof top unit with a mini split?

[GlennWest]

We did. Now mine was in need of a motor and I decided to not put anymore money in it. But it cooled way better and quiet. I went from 2 15k rooftops to 2 12k mini split and we are so much cooler and so much quieter. 

[Randyretired]

We wanted to be able to run AC using solar as we don't have power at our mountain property yet.  We have a residential refrigerator and 2,000 watts of solar.  Yesterday the afternoon high was 91 and one 12,000 btu mini split easily kept us at 74 our desired setting.  All on solar.  Our 12,000 btu mini split performs much better than the 15,000 btu RV AC.  One RV AC would not keep up with these temps and would require using both.  The mini split uses about 400 watts.  Here when the sun goes down it cools quickly so we use the mini split to heat a little in the early morning.

Mini splits use an inside unit and an outside unit and require copper lines and wires between these units.  The outside unit is to big to mount on the roof so we built a support to mount it on the back.  I drilled a 2.5" hole to run the lines, wires and drain into the Teton.  The installation is not typical and not something the average RV tech is familiar with.  It would seem to be more of a DIY task.  For us it is worth it but maybe not for many.