Don't have any hard data, but I suspect the new units are more efficient than the old ones, just like new home refrigeators are more efficient than the older ones. Main reason for this is the new scroll compressors are more efficient than the old reciprocating ones. That said, as long as yours is working well, I wouldn't upgrade. Doubt any savings would make up the cost in your lifetime.

 

Agree with Jims comments and would add that, IMHO, adding insulation and getting an airtight seal around the door goes a long way towards efficiency. I spent a little money and a lot of time adding a couple of inches of closed cell foam insualtion around the box and a double gasket (from Home Depot designed for sealing exterior doors) to the lid on my fridge and immediately saw a large decrease in Ah consumed.

 

Possible after all this time your refrigerant level is low as well.

 

30 years old and the refrigerant may be low.

A fast test is to find the amperage rating on the compressor's rating plate. Then use an ammeter to measure the draw ehn the compressor is running.

If it is rated for a 3 draw but you find it is pulling 5A...that's a sure sign it need gas. Doens't mean it is leaking badly enough to need repairs, just that there's been a slow leak, which is worth looking into, or just a recharge.

Of course a new system may be faster and cheaper, considering how hard it is to find a good cooling tech.

 

Actually your old unit is still very efficient. Danfoss makes one amazing little compressor. At 600 + dollars for a new condenser, the cost vs reliability is something to think about for sure. If the box still cools down to 38 or so and evaporator gets cold all over it's surface your refrigerant is most likely still ok. in Theory, the refrigerant should not leak out. (think of Grand Ma's old Philco or GE still running after 50 plus years) Murphy's law, will insure it will break down when you need it most and the worst possible time. Ice is still cheap however.

 

Replaced mine

I replaced my old Danfoss three years ago after it finally failed. The only significant improvement is the fan is now shrouded so it "should" be more efficient and the new one has a connection for an auxiliary fan which I installed to ventilate the compartment it's installed in. The aux fan comes on when the compressor kicks in. One thing to note is the new ones use R23 which is a bit less efficient than the older R12. I haven't noticed any large improvement in overall efficiency over my old unit.

 

Thanks to all for your replies and great information. I will have to do some further investigation next time I am aboard. My feeble recall tells me that the evaporator, which is also a small freezer compartment, ices up on only one end. I will have to verify that but if that’s so, perhaps a Freon check is in order.

Should I decide to service the unit, can anyone recommend a qualified AB service technician in the Kent Island / Annapolis area?

Thanks again for your great feedback! – Ray

 

BTW - for those looking at $600 compressors alone...I've always wondered why not get one of those Waeco CF-80's that can be had for $400 or so online and then just rip out the BD-35 compressor thats in there. Same compressor thats standalone?

Pricing of marine gear just never makes sense to me.

P.S. - I find that "precooling" your fridge with some frozen ice packs or really cold cans of soda helps bring it down to temp really easily...then the fridge works less to maintain temp.

 

There's3 or 4 models of the same compressor nightowl And a few modules also. fixed speed, variable, 12 volt, 12/48 volt Direct Current Compressors - Danfoss btw it always makes sense to replace a whole condensing unit rather then a compressor alone.