Moving on up to full time boondocking in a big honkin 50Amp Class-A - Any first hand experience??

[liamlunchtray]

Howdy All - Last year I built out a pretty capable setup in our Class C, pretty much exclusively through what I learned in these forums:

• 2420Watts of panels
• Multiplus 12|3000|120
• Smart Solar 150|100 & Smart Solar 100|50, Orion 12|12-30 DC/DC
• (2) 12v 300AH Power Queen
• Cooper & Hunter 9kBTU Minisplit

We did about 7 months of full time boondocking and it served us really well. Ideally I think 1 more 300AH battery would have made it perfect. We have since decided to sell our house and hit the road permanently. Our small Class-C is an amazing rig, but ultimately just a little too small for myself, my wife, and 2 dogs. We've decided to make the jump into the deep end and buy an older large (Likely 42') higher end RV. We're heading out into the great beyond and when we find the right rig we'll buy it. That means I will be doing this install like some wingnut out in the desert somewhere. The goal is big and simple. I'm likely going with an all in one like the EG4 type stuff (or maybe 2 in parallel?), as many panels as I can fit racked up over everything (5k watts or so?), and a big battery bank (20kwh? 30kwh?). In order to simplify things I would love to avoid another minisplit install if possible. They are absolutely the best option, but also the most complex to install. I know Im not really going to have an opportunity to use the rig first and do things the best way possible with a proper energy audit and all that good stuff.

So I was curious if anyone here has been running a large install like this without a minisplit. Was it sustainable? How many rooftop air units did you have? I'm not afraid to oversize if it means I can just run everything. I work from home and we are nerds so our power needs are always high with computers and starlink and whatever. The overhead power draw on a big rig like this is going to be dramatically more than I'm used to, so I dont feel like I have enough knowledge to guestimate.

Any first hand input would be appreciated. Hopefully this isnt entirely a "how long is string" question.

Liam

 

[HarryN]

I don't know exactly the answer, but the larger class A RVs that I have seen use 3 each 15 K btu RV type air conditioners.

Even with that, people in them talk about it not being quite enough on a really hot day.

One of my friends full times in his Class B home built setup, but a key reason why it mostly works is that he pulls a fairly healthy trailer with stuff as well and has storage units in a few places to deal with the seasons, etc.

I helped him with the power system in the trailer and in the van, built the way he wanted, but IMHO it still is not enough power to be really comfortable unless he drives to follow the seasons.

My personal conclusion is that if I were to do it, a trailer would be part of the equation, no matter the tow vehicle size. Probably also at least a 6 kW generator of some kind for use sometimes.

 

[Daddy Tanuki]

Howdy All - Last year I built out a pretty capable setup in our Class C, pretty much exclusively through what I learned in these forums:
View attachment 210237

• 2420Watts of panels
• Multiplus 12|3000|120
• Smart Solar 150|100 & Smart Solar 100|50, Orion 12|12-30 DC/DC
• (2) 12v 300AH Power Queen
• Cooper & Hunter 9kBTU Minisplit

We did about 7 months of full time boondocking and it served us really well. Ideally I think 1 more 300AH battery would have made it perfect. We have since decided to sell our house and hit the road permanently. Our small Class-C is an amazing rig, but ultimately just a little too small for myself, my wife, and 2 dogs. We've decided to make the jump into the deep end and buy an older large (Likely 42') higher end RV. We're heading out into the great beyond and when we find the right rig we'll buy it. That means I will be doing this install like some wingnut out in the desert somewhere. The goal is big and simple. I'm likely going with an all in one like the EG4 type stuff (or maybe 2 in parallel?), as many panels as I can fit racked up over everything (5k watts or so?), and a big battery bank (20kwh? 30kwh?). In order to simplify things I would love to avoid another minisplit install if possible. They are absolutely the best option, but also the most complex to install. I know Im not really going to have an opportunity to use the rig first and do things the best way possible with a proper energy audit and all that good stuff.

So I was curious if anyone here has been running a large install like this without a minisplit. Was it sustainable? How many rooftop air units did you have? I'm not afraid to oversize if it means I can just run everything. I work from home and we are nerds so our power needs are always high with computers and starlink and whatever. The overhead power draw on a big rig like this is going to be dramatically more than I'm used to, so I dont feel like I have enough knowledge to guestimate.

Any first hand input would be appreciated. Hopefully this isnt entirely a "how long is string" question.

Liam

i ran a minisplit along with the rest of a 800sqft cabin/cottage initially on 4kw of panels and 30kw of lithium batteries and had no issues at all. you are looking at 5kW of panels, 30kW of battery...

Get the minisplit you will love yourself later...

 

[jberger]

Couple of thoughts
Look for a coach chassis based unit, it will get you a much better platform to build on and weight will not be a factor. Newel, Prevost, Wanderlodge, etc.

They are an order of magnitude better built than a typical fiberglass/rubber roof RV, especially in the longer lengths and were built on million mile chassis. An old coach is normally a much better build machine than any modern RV.
These units will get you big tanks (Fresh and Waste) for longer boondocking, usually have hydronic heating which uses diesel for heat and hot water while also using very little electricity. Tons of rooftop space for solar without worrying about the integrity of the roof system, weight, etc.
Huge lower bays for equipment storage and mounting, etc. Solid electrical systems. A lot of these coach units have air driven toilets which really cuts down on water use, normally they use 1/3 the water of a standard rv toilet so that's more time between dumpstations, especially if you have a unit with a combined waste/grey tank.

Gree now makes a roof top, inverter unit that gives you minisplit type efficiency without the installation hassle. They use the same 14x14 opening as a standard roof AC but with much better results. These inverter style units will probably get you 2-3 x the runtime of a standard rooftop AC.

You say you don't want to deal with installing another minisplit, but the HVAC is probably your biggest power use over time, so that's where you need to start. Going hydronic on the heat will reduce your heating power needs by a bunch, leaving the standard RV fridge as the next place to upgrade. It seems counter intuitive, but installing an efficient residential fridge goes a long way when boondocking. You have much more space and you don't need a separate freezer either.

The coach RV normally has a huge lead acid battery bank that is simple to upgrade to LFP. Most of the time these banks are on large pull out drawers, so the physical installation isn't a problem either.

 

[justinm001]

I have a 40ft Prevost XL2 dual slide and is the perfect vehicle ever. Anything over 40 gets complicated to find spots. Ohio state parks are basically only 40ft limits and others seem to be similar. Also with 40 I get a tag so over 10k cargo capacity and very easy to maneuver in small towns.

I run mine with 2x5kw Victron Quattros 48v then a 3rd Quattro 12v. I have a crazy 6 AC units on this rig which come in handy to cool off quickly. So 4 are on the 48v inverters and 2 are on 12v. With the 12v 5kw it's a bit hard to start the 15.5k AC unit but works, never ran both at same time yet. I can run a few on the 48v side no problem.

I wish I had a smaller generator and am very tempted to remove the 20kw and replace with a Honda portable. With the solar and inverters it's not really needed.

Also we do mainly day/weekend trips and the alternator is the biggest help, so if you're planning similar I'd focus on that. It's very nice to park and know I'm at 100% when we start boondocking. Plus worst case if any issues with inverter precharging or anything I can just turn the key and use the chassis battery to get everything on.

 

[chrisski]

Running a single AC off solar while boondocking in the day could be sustainable, but difficult and expensive and involve a ground mount. Running two ACs while boondocking would not be sustainable boondocking. This would involve a ground mount that makes it homesteading. Running a single AC off boondocking 24 hours a day with a 20 kWh - 30 kWh is possible, but the array required for that would make it more like homesteading.

So I was curious if anyone here has been running a large install like this without a minisplit. Was it sustainable?

I have a fifth wheel and have enough solar to run a single roof top AC during the day.

If you're asking to run 1 roof mounted AC with roof mounted panels only, than AC during the day is, not the night. For me to run this, 1650 watts of flat roof mounted panels did not cut it. and I had to ground mount 900 watts of ground panels which I aimed towards the sun three times a day. TO actually charge the battery, I added another 300 watts for a total of 1200 watts of ground panels.

If I wanted to charge my batteries for 24 hour operation, I would want a total of 3 kW ground mount array on top of my 1.65 kw rood array. My fifth wheel could fit 3 kW of roof mounting, but then I'd have to put these panels over the AC, vents, and skylights.

Gree now makes a roof top, inverter unit that gives you minisplit type efficiency without the installation hassle.

Can you post a link. I have only found a single furion unit that is not yet available. The spec sheet for the 18k BTU inverter unit still pulled almost the same as a 15k BTU. My 15k BTU unit can't keep up over 90, so perhaps the 18 k BTU unit will.

order to simplify things I would love to avoid another minisplit install if possible.

I don't think minisplit installs are practical for larger Class A buses or even a 5th wheel like I have. These bigger RVs have vented ACs and mini splits aren't vented. Also, larger than 12 k BTU mini splits go to 240 volts, and bigger Rvs have 15 k BTU ACs. I would like to see a successful 120 v mini-split AC install on a class A or 5th wheel, but don't thinkits possible.

I run mine with 2x5kw Victron Quattros 48v then a 3rd Quattro 12v. I have a crazy 6 AC units on this rig which come in handy to cool off quickly. So 4 are on the 48v inverters and 2 are on 12v. With the 12v 5kw it's a bit hard to start the 15.5k AC unit but works, never ran both at same time yet. I can run a few on the 48v side no problem.

I take it these 6 X AC units are run off battery and can't be sustained by solar. I'm estimating this would take a 12 kW to 15 kW solar arrays to power these ACs.

In honesty, I think you need more than the two standard ACs to cool a bigger RV down.

Two takes my fifth wheel hours if its 105 F+ out, which happens half the year here.

 

[corn18]

If I were full timing, I would just follow the seasons. So much more practical than trying to cool an RV without a genset or shore power.

 

[justinm001]

I don't think minisplit installs are practical for larger Class A buses or even a 5th wheel like I have. These bigger RVs have vented ACs and mini splits aren't vented. Also, larger than 12 k BTU mini splits go to 240 volts, and bigger Rvs have 15 k BTU ACs. I would like to see a successful 120 v mini-split AC install on a class A or 5th wheel, but don't thinkits possible.

I take it these 6 X AC units are run off battery and can't be sustained by solar. I'm estimating this would take a 12 kW to 15 kW solar arrays to power these ACs.

In honesty, I think you need more than the two standard ACs to cool a bigger RV down.

Two takes my fifth wheel hours if its 105 F+ out, which happens half the year here.

Each AC is under 1500w, but running more just means they're on less often. I typically startup my coach, turn on 4+ ACs and in 15 minutes it's nice and cool then down to just 2 which will run off my alt.

It's been a while since summer so can't really remember but I think 2 15k keep my rig nice and cool, but it's extremely well insulated. Mine are ducted and I'm redoing the ceiling and ducts to make it even better. Plan is to duct all together so I can run front ones and it cools across so they're completely silent.

Blackout shades and window tint does a great job. I bought clear uv tint for my windshield but was too hard to put it on myself so is on the list to have installed.

 

[liamlunchtray]

Couple of thoughts
Look for a coach chassis based unit, it will get you a much better platform to build on and weight will not be a factor. Newel, Prevost, Wanderlodge, etc.

I think that a full on bus chassis unit is going to be out of budget, but the focus is on the semi-monocoque rigs that are just a notch lower. 2003-2008 Monaco/HR/Beaver, Country Coach, Foretravel... We have an all fiberglass rig currently and I'm not going back to the rubber roof hellscape.

 

[liamlunchtray]

Gree now makes a roof top, inverter unit that gives you minisplit type efficiency without the installation hassle. They use the same 14x14 opening as a standard roof AC but with much better results. These inverter style units will probably get you 2-3 x the runtime of a standard rooftop AC.

You say you don't want to deal with installing another minisplit, but the HVAC is probably your biggest power use over time, so that's where you need to start. Going hydronic on the heat will reduce your heating power needs by a bunch, leaving the standard RV fridge as the next place to upgrade. It seems counter intuitive, but installing an efficient residential fridge goes a long way when boondocking. You have much more space and you don't need a separate freezer either.

I was actually just looking at those Gree units - I think theyre selling them rebadged under a few different names. Looks like theyre 8.5 EER, so not nearly as good as a better minisplit, but dramatically better than a standard rooftop air. We tend to follow the seasons a good bit, so maybe that combined with a couple of the 8.5EER units would be enough to make it work without trying to find homes for air handlers and all that. We did it on our Class C, and it works great, but it was definitely a pain in the ass. I can swap out a rooftop unit in an our or so. Way less of a heavy lift than a full multi head minisplit.

 

[SoggyShoes]

I think that a full on bus chassis unit is going to be out of budget, but the focus is on the semi-monocoque rigs that are just a notch lower. 2003-2008 Monaco/HR/Beaver, Country Coach, Foretravel... We have an all fiberglass rig currently and I'm not going back to the rubber roof hellscape.

You might want to check out National RV. They made really solid rigs. Especially the ones built on the Ford F53 frames and the diesels. Those Ford F53 frames with the V10 are really solid. A mechanic told me they were originally built to be a fire truck.
We have 2001 Dolphin and love it. Their gas models had a lot of features that were usually only on diesel models like pre-plumed for washer/dryer and large holdimg tanks. Ours even has a bathtub that is perfect for washing the dog. We have taken multi-week trips with a family of 4 and a dog.
I am putting in a a 24v Victron twin multiplus 3000W system in a few months (waiting on batteries from Amy), but with the propane and generator, biggest limiting factor for boondocking has been the waste tanks filling up.

https://www.rvtrader.com/National/rvs-for-sale?make=National|7782234

 

[justinm001]

I think that a full on bus chassis unit is going to be out of budget, but the focus is on the semi-monocoque rigs that are just a notch lower. 2003-2008 Monaco/HR/Beaver, Country Coach, Foretravel... We have an all fiberglass rig currently and I'm not going back to the rubber roof hellscape.

Take a look here, there's some non-standard coaches that are super cheap. Super-C is another option. Im with you and wouldn't go back to rubber roof or even the paper thin walls many cheaper rvs have.

bus for sale near meAvailable Inventory - BusForSale.com

Looking for a bus for sale near me? We are the no. 1 leading dealer for buses for sale if you are looking to buy a bus.

busforsale.com

 

[PaulKeates]

Hi,

I am going down EXACTLY the same decision and design route as you. I recently bought a 42' 2000 Country Coach Affinity for the reasons stated above. It also includes a 12.5 KW diesel generator for backup.

Will do about 10K watts of solar using sliding rails to extend an extra panel out from both sides. About 20 - 30 KWH of 48V lithium. I'm thinking of getting the EG4 18KPV all in one + 30.7 KWH of batteries:
https://signaturesolar.com/eg4-18kpv-hybrid-inverter-system-bundle-30-72kwh-eg4-lithium-powerwall/

Will design the solar panel slides over the next couple of weeks and experiment with the first prototype. Once I'm happy with it then build + install.
I'm thinking of using unistrut for panel mounting and will make well-sealed screw holes in my roof - I don't want that coming off.

Planned batteries are only a little bit heavier than existing lead acid, but a LOT more storage.

The main reason for the larger RV is to get much more carrying capacity. Get the tag axle if you can - stability in wind / passing semi plus more carrying capacity.

And agree on the roof - solid layer of fiberglass or metal is the only way to go.

Cheers,

Paul

 

[Daddy Tanuki]

And agree on the roof - solid layer of fiberglass or metal is the only way to go.

Cheers,

Paul

this right here.... is the best advice I can think of. everyone has problems with these plastic and rubber membrane roofs. when you spend this kind of money on an item you do not want it rotting apart from roof leaks and shitty construction.

 

[justinm001]

Hi,

I am going down EXACTLY the same decision and design route as you. I recently bought a 42' 2000 Country Coach Affinity for the reasons stated above. It also includes a 12.5 KW diesel generator for backup.

Will do about 10K watts of solar using sliding rails to extend an extra panel out from both sides. About 20 - 30 KWH of 48V lithium. I'm thinking of getting the EG4 18KPV all in one + 30.7 KWH of batteries:
https://signaturesolar.com/eg4-18kpv-hybrid-inverter-system-bundle-30-72kwh-eg4-lithium-powerwall/

Will design the solar panel slides over the next couple of weeks and experiment with the first prototype. Once I'm happy with it then build + install.
I'm thinking of using unistrut for panel mounting and will make well-sealed screw holes in my roof - I don't want that coming off.

Planned batteries are only a little bit heavier than existing lead acid, but a LOT more storage.

The main reason for the larger RV is to get much more carrying capacity. Get the tag axle if you can - stability in wind / passing semi plus more carrying capacity.

And agree on the roof - solid layer of fiberglass or metal is the only way to go.

Cheers,

Paul

I probably have the biggest system here as well as the highest consumption of a mobile rig (6 ACs). That eg4 shows 100w idle consumption which is pretty good but I'm wondering if its real world consumption or just marketing. My 2x5kw Victron Quattros are at about 80w idle (2kwh per day). There's also an efficiency curve when inverting so when too high or too low it isn't nearly as efficient.

I have 5kw solar on my roof and angled on both sides along with a 20kw genset. I went victron because its great and has all the integrations/features I'd want. Biggest thing is powerassist as I can run on 15a/120v shore but still get 240v/50a in the RV, plus with the solar pumping in at the same time the batteries aren't discharging. On top of this it will autostart the genset if soc is low (haven't setup) so if cloudy day I don't even have to think of anything, plus I got the quattros which have dual inputs with auto transfer so I can set my genset to 240v/80a and adjust shore to whatever input I have when camping.

When you have an advanced system and needing to rely on it, these features are well worth the additional cost of Victron. Plus I feel having a bunch of small components and everything separated its a lot easier to find a spot and if any issues its not all offline.

 

[liamlunchtray]

Hi,

I am going down EXACTLY the same decision and design route as you. I recently bought a 42' 2000 Country Coach Affinity for the reasons stated above. It also includes a 12.5 KW diesel generator for backup.

Will do about 10K watts of solar using sliding rails to extend an extra panel out from both sides. About 20 - 30 KWH of 48V lithium. I'm thinking of getting the EG4 18KPV all in one + 30.7 KWH of batteries:
https://signaturesolar.com/eg4-18kpv-hybrid-inverter-system-bundle-30-72kwh-eg4-lithium-powerwall/

Will design the solar panel slides over the next couple of weeks and experiment with the first prototype. Once I'm happy with it then build + install.
I'm thinking of using unistrut for panel mounting and will make well-sealed screw holes in my roof - I don't want that coming off.

Planned batteries are only a little bit heavier than existing lead acid, but a LOT more storage.

The main reason for the larger RV is to get much more carrying capacity. Get the tag axle if you can - stability in wind / passing semi plus more carrying capacity.

And agree on the roof - solid layer of fiberglass or metal is the only way to go.

Cheers,

Paul

We went back and forth on something with a tag - We ended up finding a 40' (non tag) Beaver that met every one of our "wants" and is in beautiful shape. It even has stuff like both air & hydraulic leveling and the propane fridge but with the Amish Conversion already done. Im sure it wont be drive as nice as a tag but it will be loads better than our Class C.

I used all Aluminum Unistrut for the panels on our class C and its worked great. We have a fiberglass roof and I used these stainless glue down studs to bolt it down. Its rock solid with no holes in the roof. Good stuff.

Our house is already sold and we are already out on the road, so I'll be doing the install out in the desert somewhere. I love the idea of extra slideout panels but doing that buildout without a shop seems a little overwhelming. I'm going to try for some type of tilt though, even if its just manual to start.

Good luck on the build out! Be sure to post some progress pics!

 

[steined]

I'm finishing up a 3700 Watt solar build on our 45ft Tiffin Allegro Bus. I installed 3 Tosot/Gree 15K higher efficiency AC's this year as well. I really like them but they are not really made for a top down mount or ducted mount. You can make it work but you'll have to be handy. I have 48V 300Ah of capacity and 2 48/5000/70 Multi Plus IIs.

I've been running the Multi Plus IIs off of 50A this summer in my driveway to see what kind of power consumption I see over 24 hours. I have the front window facing the sun (south) which is the worst case in a CLASS A. DON'T FACE SOUTH!, but I do get partial shade in the morning and afternoon. After the last 2 months I've consumed a PEAK of 37kWh on a 98 degree day with it set to 72 inside. Plenty cold inside, but !!!!! On AVERAGE I've seen 14-17kWh consumption over the days with it at 75 inside and running them on low or dry mode which has been very comfortable.

Obviously I'm not going to get 3700 watts output all the time, so I'm going to come up short a lot where I am this summer. But this is a pretty worst case scenario and I don't think it will usually be that bad as we tend to chase the weather. Where we plan to be, the graph below is the optimistic forecasted daily yield from the Victron MPPT Calculator for the 3700 watts. The weather there is usually low 80s max and low humidity, so very little AC compared to here.


I've been pleased with the Victron set up. Very nice equipment. The MP IIs are physically larger than they need to be unfortunately, so space will be a consideration. I have a 10kW Generator and can top the batteries up very quickly with 140 Amps of MP II charging if I need/want to. If I were re-doing things, I'd have used 4 460Ah 12 V batteries or 4 100Ah 48V batteries to get more capacity. I had 4 300Ah batteries and decided to see how it goes. 4 100Ah 48Vs would probably be better as you won't need a balancer like I do with the 4 12Vs. I used a small 60aH Weize starting/LiFePO4 battery for the house side with 3 30 Amp Victron Blue chargers in power supply mode to run the 12V side of the RV. This allows me to start the generator, have some redundancy on 12V side, and handle the large amp draws of the hydraulic slides and levelers. I would have preferred to have a Victron 48-12 Orion unit and a little NOCO Lithium Starter battery , but the 48-12 Orions don't exist yet as far as I know.


Older Monaco's are, in my opinion, the best class A value out there if you stick to Dynasty and above models (steel semi-monocoque construction) and pre 2008/2009 where some had a problematic unsupported multiplex system installed. (company out of business repair not always possible). 2000-2007 vintage Holiday Ramblers and Beavers also ride on that chassis in some trims. The are very well built units. The Monaco family units ride rougher than newer models as they aren't independent front suspension however. I had a 40ft Monaco and would suggest getting a TAG if you get a Monaco as it rides and steers better. Prevost, Newell, some Foretravels have amazing builds and durability. Tiffin is probably one of the better of the current "stick built type" Class A's, but it is nothing like the ones mentioned previously.

Good luck!!! Sounds very exciting!

 

[justinm001]

I'm finishing up a 3700 Watt solar build on our 45ft Tiffin Allegro Bus. I installed 3 Tosot/Gree 15K higher efficiency AC's this year as well. I really like them but they are not really made for a top down mount or ducted mount. You can make it work but you'll have to be handy. I have 48V 300Ah of capacity and 2 48/5000/70 Multi Plus IIs.

I've been running the Multi Plus IIs off of 50A this summer in my driveway to see what kind of power consumption I see over 24 hours. I have the front window facing the sun (south) which is the worst case in a CLASS A. DON'T FACE SOUTH!, but I do get partial shade in the morning and afternoon. After the last 2 months I've consumed a PEAK of 37kWh on a 98 degree day with it set to 72 inside. Plenty cold inside, but !!!!! On AVERAGE I've seen 14-17kWh consumption over the days with it at 75 inside and running them on low or dry mode which has been very comfortable.

Obviously I'm not going to get 3700 watts output all the time, so I'm going to come up short a lot where I am this summer. But this is a pretty worst case scenario and I don't think it will usually be that bad as we tend to chase the weather. Where we plan to be, the graph below is the optimistic forecasted daily yield from the Victron MPPT Calculator for the 3700 watts. The weather there is usually low 80s max and low humidity, so very little AC compared to here.
View attachment 237864

I've been pleased with the Victron set up. Very nice equipment. The MP IIs are physically larger than they need to be unfortunately, so space will be a consideration. I have a 10kW Generator and can top the batteries up very quickly with 140 Amps of MP II charging if I need/want to. If I were re-doing things, I'd have used 4 460Ah 12 V batteries or 4 100Ah 48V batteries to get more capacity. I had 4 300Ah batteries and decided to see how it goes. 4 100Ah 48Vs would probably be better as you won't need a balancer like I do with the 4 12Vs. I used a small 60aH Weize starting/LiFePO4 battery for the house side with 3 30 Amp Victron Blue chargers in power supply mode to run the 12V side of the RV. This allows me to start the generator, have some redundancy on 12V side, and handle the large amp draws of the hydraulic slides and levelers. I would have preferred to have a Victron 48-12 Orion unit and a little NOCO Lithium Starter battery , but the 48-12 Orions don't exist yet as far as I know.


Older Monaco's are, in my opinion, the best class A value out there if you stick to Dynasty and above models (steel semi-monocoque construction) and pre 2008/2009 where some had a problematic unsupported multiplex system installed. (company out of business repair not always possible). 2000-2007 vintage Holiday Ramblers and Beavers also ride on that chassis in some trims. The are very well built units. The Monaco family units ride rougher than newer models as they aren't independent front suspension however. I had a 40ft Monaco and would suggest getting a TAG if you get a Monaco as it rides and steers better. Prevost, Newell, some Foretravels have amazing builds and durability. Tiffin is probably one of the better of the current "stick built type" Class A's, but it is nothing like the ones mentioned previously.

Good luck!!! Sounds very exciting!

So you'll have 3700w of solar and still plugged into your 50a house? Have you thought about getting the Victron energy meter for your house then you can use the solar to power your house loads? I planned on this but when the part came I moved and new place doesn't allow rvs.

 

[chrisski]

I'm finishing up a 3700 Watt solar build on our 45ft Tiffin Allegro Bus. I installed 3 Tosot/Gree 15K higher efficiency AC's this year as well. I really like them but they are not really made for a top down mount or ducted mount.

Do you have any specs on this like a measured wattage draw?

I measured my generic 15k Roof AC at 1470 watt draw, but the TOsot Gree only advertises 10-14 amps draw, which is 1200 watts to 1680 watts. I would not mind getting a high efficiency AC, but I'd want one I know I'd use less energy, not either it'd be 20% more efficient, but could be 20% less efficient.

To run my rooftop AC it comes to about a 1700 watt draw on the battery with inverter efficiency losses and requires 2100 - 2500 watts of panels depending if its summer sun high in the air or fall sun with the sun lower to the horizon. This AC never shuts off and will be running all day long.

Thanks.

 

[Zwy]

Do you have any specs on this like a measured wattage draw?

I measured my generic 15k Roof AC at 1470 watt draw, but the TOsot Gree only advertises 10-14 amps draw, which is 1200 watts to 1680 watts. I would not mind getting a high efficiency AC, but I'd want one I know I'd use less energy, not either it'd be 20% more efficient, but could be 20% less efficient.

To run my rooftop AC it comes to about a 1700 watt draw on the battery with inverter efficiency losses and requires 2100 - 2500 watts of panels depending if its summer sun high in the air or fall sun with the sun lower to the horizon. This AC never shuts off and will be running all day long.

Thanks.

Did you see the video I did comparing a roof air to the mini split on my truck camper? Way more efficient with the mini split. Roof air I started at 80°F with high humidity and after 15 minutes it dropped 1°F, at 1/2 hour it dropped another 1°F. This consumed 30Ah from the 24V 280Ah battery.

Running the mini split and starting at 89°F with high humidity, and yes, I did open up the windows while charging battery back to full to get the humidity back inside, the temp dropped to 84°F in the first 15 minutes. By the half hour mark it dropped to 80°F while wattage draw was 35% less. It would have been even more but I had the inside fan on high. Running on auto would probably shave another 10% off. For some reason I did not record the Ah used but it was less than 8.5% so about 24Ah used. Where the mini split really shines is after initial cooldown, the thing just sips power.

The efficiency for watts used with that much heat energy removed makes the heat pump way more efficient. My roof unit had a perfectly clean condenser and evaporator plus the refrigerant charge is correct. I work on ac systems daily so I know it was working at peak performance.

The noise factor is a bonus. So much quieter with the mini split. You can hear the difference in the video.

 

[chrisski]

Did you see the video I did comparing a roof air to the mini split on my truck camper? Way more efficient with the mini split. Roof air I started at 80°F with high humidity and after 15 minutes it dropped 1°F, at 1/2 hour it dropped another 1°F. This consumed 30Ah from the 24V 280Ah battery.

Running the mini split and starting at 89°F with high humidity, and yes, I did open up the windows while charging battery back to full to get the humidity back inside, the temp dropped to 84°F in the first 15 minutes. By the half hour mark it dropped to 80°F while wattage draw was 35% less. It would have been even more but I had the inside fan on high. Running on auto would probably shave another 10% off. For some reason I did not record the Ah used but it was less than 8.5% so about 24Ah used. Where the mini split really shines is after initial cooldown, the thing just sips power.

The efficiency for watts used with that much heat energy removed makes the heat pump way more efficient. My roof unit had a perfectly clean condenser and evaporator plus the refrigerant charge is correct. I work on ac systems daily so I know it was working at peak performance.

The noise factor is a bonus. So much quieter with the mini split. You can hear the difference in the video.

Don’t think a mini split would work. I wish it did.

120 volt 12k BTU Mini splits won’t work to cool a fifth wheel with 300 sq feet of cabin area. They are great for smaller rigs. Above 12 k BTU, they turn into 240 volts.

I have a 15 k BTU unit and won’t put a smaller one in.

 

[steined]

Did you see the video I did comparing a roof air to the mini split on my truck camper? Way more efficient with the mini split. Roof air I started at 80°F with high humidity and after 15 minutes it dropped 1°F, at 1/2 hour it dropped another 1°F. This consumed 30Ah from the 24V 280Ah battery.

Running the mini split and starting at 89°F with high humidity, and yes, I did open up the windows while charging battery back to full to get the humidity back inside, the temp dropped to 84°F in the first 15 minutes. By the half hour mark it dropped to 80°F while wattage draw was 35% less. It would have been even more but I had the inside fan on high. Running on auto would probably shave another 10% off. For some reason I did not record the Ah used but it was less than 8.5% so about 24Ah used. Where the mini split really shines is after initial cooldown, the thing just sips power.

The efficiency for watts used with that much heat energy removed makes the heat pump way more efficient. My roof unit had a perfectly clean condenser and evaporator plus the refrigerant charge is correct. I work on ac systems daily so I know it was working at peak performance.

The noise factor is a bonus. So much quieter with the mini split. You can hear the difference in the video.

Yes, I was going to install a mini split, but there really isn't enough room in my layout to have a good location for the head unit. I'd need 2 to cover the whole rig and probably an 18K for the front. The Tosot/Gree rooftop units work very well and draw between 900 Watts on dehumidify to 1200-1250 watts on AC high.

They have downsides however.

• No condensate pumps (I installed one outside the unit)
• No top down installation without drilling through the plastic/base pan (giant PITA)
• Full ducted installs (no square return vent) require relocating the control panels out of the ceiling plenum to the AC unit itself if you want to keep the WiFi functionality and IR remote extenders need to be utilized if you want to set the temp (PITA)
• There is no integration with a fuel source furnace on the Tosot thermostat, so you need to keep your existing thermostat to run the gas furnace / aqua hot. (Not a huge deal, just have to remember to set the gas heat on super cold nights)
• When on AC mode the inside fan circulates constantly. Each one uses 30-40 watts all the time as a result

Pros:

• It is so much quieter than the old 15K Mach 8 heat pumps it's not even funny. Both inside and out. The old Mach 8's were annoying for me and my neighbors! The inverter type soft start is very nice and you can barely tell the difference between compressor on and off.
• Capacity seems to be VERY good. Perhaps my MACH 8's were tired?
• I run them on low with super humid days and they don't freeze up and make the inside very comfortable. With the MACH 8's I had to run them on HI when it was hot with high humidity or they'd freeze up. Especially the one by the door in front. As a result the temp can be set higher and it's more comfortable
• Much lower power consumption than the Mach 8s. I didn't have the MP IIs installed prior to the Tosots, but the Mach 8s would easily pull 15 or 16 amps while running. The Tosot was pulling 9-12 TOPS. I think I saw 13 once.
• Modern and nice looking air distribution box (I didn't get to benefit from this)
• Dehumidfy mode where it slows everything down to try to extract more moisture. Works well, but still overcools at night when it's high 70s and humid.
• Heat Pump puts out very good heat, but does draw more power than the AC side.

So if you have a ducted system and a return grille, you can probably make the Tosot work, you might just want to go to Premeir Products and buy the ducted eco cool and deal with not having the wifi though too. https://ecocool.premierproducts.net/

If you have ducted and no return grill, you better be good at wiring, sourcing IR repeaters, DC power supplies, etc etc etc AND be good at making templates to install in top down where there is no provision for it. We made it work but it was a PITA.

 

[Zwy]

Don’t think a mini split would work. I wish it did.

120 volt 12k BTU Mini splits won’t work to cool a fifth wheel with 300 sq feet of cabin area. They are great for smaller rigs. Above 12 k BTU, they turn into 240 volts.

My truck camper had an 11K BTU roof air. I replaced it with the 9K BTU Senville. The Senville outperforms the roof air as shown in the video.

More efficient not only on power usage but also moving heat energy. That was the point of my post above, the change in temp inside over the first half hour shows just how much more efficient it was. While the roof air was comfortable after a half hour, the temp had not moved much. It removed the humidity which made it more comfortable. The mini split not only removed humidity but also dropped the temp by over 400%. I think part of this is due to the mini split outside unit is in the shade more than the roof air. The roof air gets exposed to higher temps and is in direct sunlight. The condenser delta T to ambient temp is much higher on the mini split mounted in the shade, even if partial shade. This allows much higher heat transfer.

I have a 15 k BTU unit and won’t put a smaller one in.

Most likely the 15K BTU roof unit is not as efficient at moving heat energy as a 12K BTU mini split.

There are some RV roof mounted heat pump units out there but those will not be cheap. It says RV in the description so the price gets jacked up quick. Roof mounted may suffer from a much lower delta T during the day compared to a mini split mounted in a shaded position.

 

[justinm001]

My truck camper had an 11K BTU roof air. I replaced it with the 9K BTU Senville. The Senville outperforms the roof air as shown in the video.

More efficient not only on power usage but also moving heat energy. That was the point of my post above, the change in temp inside over the first half hour shows just how much more efficient it was. While the roof air was comfortable after a half hour, the temp had not moved much. It removed the humidity which made it more comfortable. The mini split not only removed humidity but also dropped the temp by over 400%. I think part of this is due to the mini split outside unit is in the shade more than the roof air. The roof air gets exposed to higher temps and is in direct sunlight. The condenser delta T to ambient temp is much higher on the mini split mounted in the shade, even if partial shade. This allows much higher heat transfer.


Most likely the 15K BTU roof unit is not as efficient at moving heat energy as a 12K BTU mini split.

There are some RV roof mounted heat pump units out there but those will not be cheap. It says RV in the description so the price gets jacked up quick. Roof mounted may suffer from a much lower delta T during the day compared to a mini split mounted in a shaded position.

I've never understood why heatpumps on rooftop ac units. Heat from the ceiling doesn't really work in a vehicle that isn't energy efficient, the heat just escapes out the roof before actually warming and there's not enough circulation to get to the bottom anyways.

I have toekick electric heaters which work great but horrible on electricity. I put in a diesel heater and it sipped fuel last winter, didn't even hookup the fuel line and just used the tank in a bay. They aren't extremely reliable and i wouldn't leave it on when not around though.

Still trying to find a good solution for heat. I'd love radiant heating with coolant/water in floors or on walls with an aquahot or something custom/similar where I can run electricity/diesel/engine but haven't found out one that doesn't take a bunch of room. Might go electric floor heat but its 240v and EXPENSIVE plus not energy efficient.

 

[steined]

I've never understood why heatpumps on rooftop ac units. Heat from the ceiling doesn't really work in a vehicle that isn't energy efficient, the heat just escapes out the roof before actually warming and there's not enough circulation to get to the bottom anyways.

I have toekick electric heaters which work great but horrible on electricity. I put in a diesel heater and it sipped fuel last winter, didn't even hookup the fuel line and just used the tank in a bay. They aren't extremely reliable and i wouldn't leave it on when not around though.

Still trying to find a good solution for heat. I'd love radiant heating with coolant/water in floors or on walls with an aquahot or something custom/similar where I can run electricity/diesel/engine but haven't found out one that doesn't take a bunch of room. Might go electric floor heat but its 240v and EXPENSIVE plus not energy efficient.

My coach has 120V radiant floor heat. It's wonderful when connected to shore power. It has 2 15 amp zones (Front/rear) and does a great job due to the thermal mass of the floor tiles. Certainly not energy efficient