NOVA KOOL R5810 Selection and Installation Guide

[Geronimo John]

BLUF:  This post has two parts.  First, below is a brief summary as to how I became interested in the Nova Kool R5810 as a replacement for our Dometic.  The attachment is an installation guide that may serve other OTT LE2 owners as a good starting point should they choose the Nova Kool unit as a DYI upgrade.   

After reviewing John Davies Dometic “demo” post, I decided I ought to start getting my head around the options to upgrade our Dometic RM2454.  My list of requirements for an upgraded refrigerator are:   

·       It must fit into the existing cabinet.

·       Does not use an absorption design 

·       Has at least the same freezer size as our existing Dometic RM 5424 (11 Liters)

·       Has more total cooled space than the Dometic’s 4.0 cuft

·       Will pass through the OE2 entry without full disassembly

·       Uses the Danfos/Secop vapor-compression compressor for great efficiency

 

NOTE:  If you are not familiar with the Danfos/Secop compressors, here are a worthwhile video:       https://www.youtube.com/watch?v=jl5IWkGSfJY&t=7s

 

Specifications for our OEM Dometic and two proven replacements are as follows:     

 

Model	DOMETIC	ISOTHERM	NOVA KOOL
	RM2454	CRX1140	R5810
Refrigeration technology	Absorption	Secop Comp.	Secop Comp.
US Cubic Feet	4.0 Cu Ft	4.8 Cu Ft	5.8 Cu Ft
Freezer (Liters)	11.4 L = .4 Cu Ft.	6.0 L = .21 Cu Ft	11.4 L = .4 Cu Ft.
Input frequency		50/60 Hz	50/60 Hz
Input voltage (AC)		100-240 V	100-240 V
Input voltage (DC)	12/120 V	12/24 V	12/24 V
Rated input power		65 W	52 W

 

Both the ISOTHERM and NOVA KOOL are huge improvement over the Dometic.  But for our Ollie, we need the freezer space that the Nova unit provides.  Having an extra cubic foot of refrigerator space and meeting all of the above requirements…. made the decision easy for us.  If you are not familiar with the Nova Kool R5810, here is a review:    https://www.campervan-hq.com/blogs/gear-update/campervan-hq-gear-update-nova-kool-refrigerators

 

Next was how to install the Nova Kool.  I ran across Ken’s (Mountainoliver) post about his 2019 installation of a Nova Kool R5810.  Our forum, then PM’s, lead to conversations that were off the charts beneficial.  Ken sent many pictures and our communications filled in the holes. 

The attached “Nova Kool R5810 Installation” document is based upon and uses info from:

·       John E. Davies thread “Compressor Fridge Info Thread, for those of us considering switching” posted May 11, 2018 in Ollie Modifications. 

 

·       Randy’s (Try2Relax) 22 JUNE 2018 follow-up post

 

·       Ken’s (MountainOliver) 23 SEPT 2019 follow-up to Randy’s Post and much non-posted documentation

Combining their exceptional craftmanship (Far beyond my skills), and a few technical Mechanical Engineering mods, Ken and I believe the attached plan may serve other owners as a good starting point should they choose the Nova Kool unit as a DYI upgrade.

Ken and I encourage your thoughts and suggestions for further refinement.

GJ

Nova Kool R5810 Installation Guide.pdf

[Mike and Carol]

Good work on this GJ and Ken!  This will be a great resource for many.  Mike

[mossemi]

Excellent procedural write up!  I had forgotten Ken’s Nova Kool installation posting.  Thank you both for sharing you experiences.  And the thermal switch you are thinking about was part of my refrigerator fan replacement project and has been in service for over 2 years.  It’s a winner!

Mossey

 

[John E Davies]

Very nice article, especially for those who lean toward metal fabrication vs wood. One important note:

“If using the Nova Kool AC/DC version, both existing AC and DC power feeds MAY be utilized. Check The Manual. Also be sure to check YOUR fuses and adjust them per the Manual.”

The fuses installed originally during the build “should” be the right ones, but a previous owner might have messed them up. The purpose of a fuse is not to protect the appliance or device at the far end, rather it is to protect the WIRING from burning up….. So you can install a 7.5 amp fuse in a 15 amp DC circuit, no problem, but never add a larger one than is specced for that gauge of wire!

I have ground to a halt in my isotherm install, from a rather nasty cold that won’t go away, but I too noticed that my floor was not built “true” from side to side. So I leveled the trailer carefully in all directions and found that NOTHING about the fridge cavity was either true or straight. Wonky would be the best description…. That is why I decided to remove as much of it as possible and install my own wood framing, so I could get the floor flat and at true right angles to two truly PARALLEL and hell-for- strong side support columns.

You haven’t mentioned ventilation requirements. My Isotherm Cruise 130 manual says a 9 cm/ 3.5” diameter round hole (39 sq inches) at top and bottom should be provided. But you must keep in mind the restriction caused by a grill or hvac register, which may be huge. Another Isotherm manual called for 5 cm (2”) vertical clearance everywhere that air flows. I chose to follow the latter and made sure there was that much at top and bottom.

Then there is the unforeseen “restriction” of a big dog flopped down in front of that bottom opening, or a Clam tent or duffle bag. I added a secondary lower vent in a different location in case that happens.

I will post a thread about my Isotherm install, it will be a while tho.

FYI if you want an inexpensive TOUGH high flow option for air vents, that can’t be accidentally broken, cut your own neat openings and add this expanded aluminum behind them. It’s about $14 per square foot.

 

John Davies

Spokane WA

[SeaDawg]

Level in the cavity isn't a big deal with dc/danfoss/secop fridges. Built for boats.

Ventilation is.

Btw, I'm not totally sure, but I don't think the Novakool will fit through the "neck" of the early Elite I s.

[Geronimo John]

19 hours ago, John E Davies said:

My Isotherm Cruise 130 manual says a 9 cm/ 3.5” diameter round hole (39 sq inches) at top and bottom should be provided.

POST Rewritten for clarity.  GJ

JD:  Good comments all!

The Nova Kool requires 30 square inches of cooling vent at both the top and bottom of the compartment.  With this install, we have about 46 square inches at both the top and bottom.  This of course has to be reduced by the "free air flow" of the vent screens chosen.  In my attachment (Page 9) I suggested at least 50% free air which is about what Ken used successfully for his camping environments.  This is 7 sq inches short on the top (only).  On the bottom we have suggested drilling holes into the aft side wall low for additional in-flow of cooling air. 

The short fall has not impacted Randy or Ken's installations.  However, my Belt and Suspenders are those two fans on top as my starting point due to our consistent HOT weather camping.    

From a free air perspective, your suggestested flattened expanded screen I believe would have less exit air flow resistance.  However, Ken's custom shop built one is "knock my socks off" beautiful.  Personally, if I can afford it, I would go with Ken's design for the top vent.  And for cost containment a screen as you suggested as it pretty much will not be seen unless I'm scrubbing the huge expanse of flooring in our OE2's.   🙂

Finally, If my HOT weather install keeps the fans running more than about 40% of the time, I'll find the posting about vents that has the great looking vent and install it high in the cabinet on the entrance door side.  But frankly, I don't think it will be needed.

GJ 

[Geronimo John]

4 minutes ago, SeaDawg said:

 

Btw, I'm not totally sure, but I don't think the Nova Kool will fit through the "neck" of the early Elite I s.

Roger that.  My write-up was for the OE2's.  The Elite ones need to triple measure.

GJ

[SeaDawg]

21 minutes ago, Geronimo John said:

Roger that.  My write-up was for the OE2's.  The Elite ones need to triple measure.

GJ

Got that. Just threw it in for Elite I  owners, like us, who might look at this thread in future years .

Thanks for that. 

Our isotherm/truckfridge requires much less ventilation  from what you stated. I don't know why. I'm remembering  (could be faulty) about half.  We also rarely camp in high heat conditions,  but no issues whatsoever in the past years. 

More ventilation is better than less, for sure.