Max Burton fridge/freezer

[regis101]

For nine bones , I'd be looking at an ARB or equivalent

 

[mayble]

Don't forget to check prices on ebay, if you're in the market.
That's where I found mine, at a very good price ($359 for the 53 qt model).

 

[anthrit]

Thanks Sternwake. I will like the Truck fridge. See my issue is that I am dealing with a limited space. 24" x 23.5". The Max Burton was just the right size. However the Truck Fridge on their largest model will fit my spot with space to spare. I wanted a Dometic but they are way over sized for how much quarts I need. I did find another one that would fit the space called a Whynter but not sure how it will hold up.

Whynter FM-45G 45-Quart Portable Refrigerator/Freezer, Platinum https://www.amazon.com/dp/B002W8BLUG/ref=cm_sw_r_cp_apa_pfqEzb36Y4V8S

 

[John61CT]

Anyone know any portables include the larger Danfoss BD80F compressor?

 

[anthrit]

Well, after watching Bob's video on the 51 model Truck Fridge I decided to get the same one that he got. I just can not wait forever for the Burton to come back in stock. However I feel like I made the better choice in the end. Seems ppl complained about the plug & ppl here modifying cooling on the Burton anyways.

 

[John61CT]

Is it true that Whynter and TruckFridge are the same?

Are they part of Waeco/Dometic like these Burtons?

Is Secop/Danfoss still independent, or did they also get acquired?

I'm trying to sort out which brands use "genuine Danfoss" as opposed to Sawafuji, and then presumably inferior knockoffs

 

[regis101]

Good on ya.  Thats why we're here.  

After you obtain the 51 perhaps you can start a thread with some pics and specs.  Truck Fridge has been on my radar for a long time.  I'd be interested in knowing how other fridges handle extreme ambient heat. Especially where I'm at. I can't remember the last time we've had this many 90+ degree days in a row. The other day it was 121* in the van. yowie.

I'm on a mac. Tried to do the degree sign shortcut. epic fail. sorry

 

[regis101]

One more then I'll leave ya alone.  This is a Max Burton thread with some side to side drifting and thats expected.
Here is a copy/paste from Truck Fridge showing parts for the 51 Portable.  The compressor coiling is similar to the MB.  I'd be curious to know what compressor they use.  The 49, if memory serves uses a smaller radiator condenser. Maybe to overall size or something. Lots of good info on their site.
http://www.truckfridge.com/wp-content/uploads/2017/04/TB51A.pdf

 

[Silver6gen]

Hey I'm back to update my original post....  And Wellll.............................  Unfortunately...

Max is still trucking along like a boss!  
Some additional notes for everyone:

• The refrigerator compartment fluctuates between 44-49 when the freezer compartment is set to 24.  I theorized this was due to excessive heat in the compressor compartment
• The lid seems to pass more thermal energy from the inside out.  Would love to have a thermal camera to look at this, but this is just based on touch.
• I anticipate the first break to be a lid latch.  They are not as robust as I'd like and believe that repeated slamming of the lid will break one of them some time
• Buyers NEED TO ADD INSULATION to this fridge.  I'm looking at getting a thermal cover made for one of the other fridge makers to use for Max in addition to my reflectix and foamboard
• The fridge case appears to almost be a carbon copy of the Dometic Waeco CFX 35/40
  

I applaud your inquisitivness.

The fan is an 80mm fan, the open end shown is the suction side.  Can you see where this fan's wires run?  Can you access them, or follow them to where they enter the compressor controller?  It looks like there is a pretty good gap inbetween condenser and the casing/cover?  More than 25mm/ one inch?

The compressor is a cute little thing.  It does look like the air circulation over it is limited by the wiring bundle.  The fan will be pushing some preheated air from condenser at it.  the compressor generates heat too so it is better that the fan blows 

That condenser is not really all that efficient, with not much surface area, and part of it well away from the fan's flow, but these fans tend to have 4 hotspots which exit fan at wider angles when unrestricted.  not sure in that configuration.

what are the dimensions on the  venting grates.  Could a 120MM( 4.75" fan be attached to the inside of them?  how about a 92mm(~4 inches)?


I think I would either try adding a fan to blow cool air directly into the existing fan, or if easier, locate it to exhaust on the other side of the compartement.  Fans tend to do better with restrictions in front of rather than behind the blades.

It appears as if that existing 80mm  fan would be very hard to remove and replace, so i would Aim to supplement the airflow either by forcing more air into the condenser, or haviing an Exhaust fan sucking the heat out and forcing it out the regular exit.

The Noctua NF-f12 at only 0.05 amps is likely a lesser amperage draw than the 80mm fan they used and will likely not overload the circuit intended to power the fan, if added to it.

If I owned that fridge, i would likely attach the NF-f12 to the casing interior , oriented to blow into the existing fan, and likely open up some of the grating.  I am usually not worried about warranty voiding though.  Once I establish it works properly I will modify.

You could also perhaps add some refelctix in between cooling unit and the fridge box itself to reflect the heat generated there from entering the cold portion of the box.

The coler you can keep that cooling unit interior, the longer the compressor and compressor controller will last.  The earlier danfoss bd35f' s failures were from teh compressor controllers overheating when there was a huge heat load placed in the fridge in hot ambient temps.  They soon added a finned heatsink on the back of the compressor controller.

Splicing the wiring that leads to the existing fan is pretty simple.  The controller should easily handle the 0.05 amps extra of the NF-f12 fan, and this fan should be able to pump ~53 cubic feet od air per minute through the cooling unit.  the existing fan likely recirculates 50% or more of the air it moves, whereas a fan on the casing should exchange nearly all the air it moves, which will lead to improved cooling nad extended cooling unit lifespan, and allow for shorter compressor run times, reducing overall battery consumption and allowing it to run for longer in hot ambient temps.

Thanks for the effort of the  providing the pics.  You have done everybody who reads this thread well to have done so.

The fan wires are usually red and black and about 22 gauge.  One of them is likely sharing the ground with the main ground from the input plug, the other wire might have a dedicated output just for it.

Not sure of the sizes but some piggyback connectors can make attachng an additional fan easy without any wire splicing.

https://www.amazon.com/0-250-Female...63&keywords=crimp+connectors+quick+disconnect

if worried about warranty one can make it appear as if no modificatons were  ever added.  I'd use amazing goop to glue a NF-f12 fan to the side opposite the existing fan and use the piggy back connectors.

Since you have it open, and perhaps do not require the 'portable' moniker anymore, consider bypassing the powercord connector and running 10 gauge wire right to compressor controller. The move voltage one can deliver to the compressor controller, the better it will run and be slightly more efficient too.

I completely agree with your assessment.  I will be adding a case exhaust fan that will run when the unit is on, or when the solar panel is receiving charge (easy signal voltage that also indicated the rig is in direct sunlight and could be hot).  Some basic anderson power pole connections and diodes should make this work.  Additionally I am going to line the compartment with reflectix or foam to try and reduce the cases ability to heat soak from the compressor unit.  And at some point I am going to duct the exhaust to the outside, not sure if it's worth ducting the intake.  Thoughts?

Here is a photo of it again since photobucket decided they didn't want members anymore.  And to whomever asked about my rig it is a 1993 Toyota Land Cruiser (FZJ-80)

 

[John61CT]

> The refrigerator compartment fluctuates between 44-49 when the freezer compartment is set to 24.  I theorized this was due to excessive heat in the compressor compartment

Personally I prefer a colder freezer, more like 15°

I assume that would make for a safer fridge also?

But venting the work area helps with efficiency so much should do anyway, so may well end up with those temps with little more consumption.

> The lid seems to pass more thermal energy from the inside out.  Would love to have a thermal camera to look at this, but this is just based on touch.

Those infrared gun thermometers are super cheap, paid $11 for one including shipping from HK.


> Buyers NEED TO ADD INSULATION to this fridge.  I'm looking at getting a thermal cover made for one of the other fridge makers to use for Max in addition to my reflectix and foamboard

For built-in install I would think a well sealed thick foam custom box, would work better than any portable cover.


> The fridge case appears to almost be a carbon copy of the Dometic Waeco CFX 35/40

I assumed from the beginning (see my post #18) that Max Burton is Waeco's customer, just import in bulk slap a label on to resell them.

 

[highdesertranger]

is that as cold as you can get it to go? in other words do you have it turned down all the way? what's the ambient temp? highdesertranger

 

[Silver6gen]

> The refrigerator compartment fluctuates between 44-49 when the freezer compartment is set to 24.  I theorized this was due to excessive heat in the compressor compartment

Personally I prefer a colder freezer, more like 15°
I understand however my freezer compartment is mainly used as a fridge / mild freezer.  

I assume that would make for a safer fridge also?

Yes it would

But venting the work area helps with efficiency so much should do anyway, so may well end up with those temps with little more consumption.
Project for tonight

> The lid seems to pass more thermal energy from the inside out.  Would love to have a thermal camera to look at this, but this is just based on touch.

Those infrared gun thermometers are super cheap, paid $11 for one including shipping from HK.

Yup I know, HF has them for cheap too.  I was talking about a thermal camera as it would be very easy to see the leaks.  May still buy what your talking about though.

> Buyers NEED TO ADD INSULATION to this fridge.  I'm looking at getting a thermal cover made for one of the other fridge makers to use for Max in addition to my reflectix and foamboard

For built-in install I would think a well sealed thick foam custom box, would work better than any portable cover.
Yes it would, I purchased the Dometic CFX 40 insulated cover.  It will have roughly an inch of extra space on all sides, perfect for adding foam on all sides.

 

[Silver6gen]

is that as cold as you can get it to go?  in other words do you have it turned down all the way?  what's the ambient temp?   highdesertranger

[size=medium]No it will go down to the max setting -7.  I tested it on a hot day.  Did pretty well.[/size]


OK so I installed a 9225 .3amp fan on the exhaust port, it's a Shenzhen Shimao Technology Co.,Ltd. SM9225 SH12 I had laying around (couldn't find specs but its likely a ~45CFM fan)[size=medium].  I created a shroud to prevent leaks then blocked the two side ports, this will force 99% of the air to come all the way through the case.  Right now the fan is connected to condenser fan through a relay, it it makes a large impact going to replace this fan with a 92mm temperature controlled variable speed fan.[/size]

Wasn't able to add any insulation tonight, we'll see what the fan is able to do.

 

[Silver6gen]

Also note that the condenser fan is negative switched.

 

[Silver6gen]

It's too bad the Burtons aren't cheap anymore, they are right up there with the Waecos.  Anyway, this is how I have my fridge insulated right now, The lid has two layers of reflectix on the outside and one on the inside and the fridge compartment is lined on three walls and the floor and I did end up lining the compressor compartment last night.  Any thoughts on improvement?

Also doing a test run down to -7.  Its 80% loaded with items that came out of the fridge so its taking longer than usual but the fan is definitly helping.  Also measured current draw while it was chugging away and it was sitting at 2.88 amps with the engine off batt at 12.4v, then 2.61amps when the engine was on 14.0v.  That current is the fridge and .3amp fan..

The upper temp is the freezer compartment, lower is ambient.

 

[highdesertranger]

no images on my end? highdesertranger

 

[Silver6gen]

 

[Silver6gen]

2° was the best Max could muster today. Ambient temp is climbing quickly into the 90's so I backed it off to give it a break. Almost a 100° spread is pretty impressive. Also the battery was floating right at 13.3 volts, looks like the solar kicking out enough to provide all of the freezers demand and then some, solid test.

 

[John61CT]

Reflectix is not actually at all insulating.

I would think does nothing inside a fridge's insulation.

Will help on the outside of all insulation reducing radiant heat gain.

If I had the space I would go for at least 2", ideally 4" all around the six sides, with the top perhaps being firm sitting/sleeping foam.

With "tunnels" cut for active venting to and from the working area, but otherwise glued/caulked to keep things as tight as possible.

 

[regis101]

I did a shakedown run a coupla weeks ago fer a few days at the local campground.  Babysat the solar and fridge and took lots of notes.  I kept mass in the fridge for thermo dynamics.  The caveat to this is that the fridge was tempered with shore power 24 hrs in advance of pulling out of the driveway.  Meats were prefrozen and placed on the bottom of basket.  Salad fixings and fruit was placed on top of that.  

Yes, I'm a noob.

The daily high was ~90.  Daily low was ~65.  The Perseid showers were just starting and it was a full moon.  Plenty of tasty adult beverages on hand.

The MB - 37 qt. ran strictly off solar.  I was taking volt and amp readings from the Rover 20a controller LCD screen.

Basically ,  on average, it drew 3.2 amps.  The run cycle time was seven minutes at 50 minute intervals.  Again , on average.  The seven minutes was dead on each time.  The cycle time interval depended on ambient temp.  Shortest cycle time was 45 minutes and longest cycle time was 90 minutes.  

One of my first notes read as follows,  Set fridge temp to 33*- started draw of 2 amps-rose to 3.27amp- sounds like running faster- 3.40 amp

Second note later that day,  van temp of 90*- fridge kicked on-amperage bouncing around- 2-4 amps, - 3.7-4.2 amps, seven minute run time.

Another note next day or something, fridge set at 36*- bottom of basket thermo reads 40* upper fridge is 58*- 3 minutes into run 3.5 amp avg- 3.5 minutes speed increases, amps increase to 4.1, 4.5 minutes- 3.9-4.0 amp, 5 min- fan or comp still fast-3.5 amps, 6 minutes- 3.5-3.9 amps. 7 minutes - shuts off.

So, For me this thing averages 3 amps and a 7 minutes run time.  Time between run cycles varies depending on ambient temps.  Like clockwork, half way thru the run cycle the speed of the fan and/or compressor would increase.  I'm ok with that.  Dunno why though.  I suspect that it may draw a wee bit less as it ages and things loosen up.  
To me, for what its worth, it was money well spent.