Thursday, May 2, 2013
Got questions? We have the answers and some Images
Do I need water-cooling for the fridge and freezer?
No. For the amount of heat/hour the Mexicolder removes from the box, water-cooling is ABSOLUTELY unnecessary, In fact, with a water-cooled system, the energy to power the pump uses more precious amp hours.
We are concerned about the heat from the system warming the interior of the boat in the tropics.
The radiant heat from sunlight on the deck, cabin and hull far exceed the heat produced by the Mexicolder, in short you won’t notice the difference. Boiling a kettle of water for 2 cups of coffee or cooking creates much more heat than a Mexicolder.
I have seen keel cooled systems advertised that do not need a fan or a pump, will this work for me?
Yes, we built several prototypes that worked, BUT…….. Nothing comes for free and for this reason Mexicolder uses air cooling, When you are hauled out for underwater maintenance the keel cooling system did not work and when left on it damaged the compressor which is the heart of the system. Imagine being in a boatyard for even a few days and loosing those cold drinks and ice when you need them the most? Not to mention a freezer full of meat or seafood. In addition to the former you have to bore a 1 ½” hole though the hull and pay for the haul, launch and labor to do so. Even though keel coolers are made of bronze they are still susceptible to stray current corrosion. You don’t need to haul out to install a Mexicolder, or ever need worry about future corrosion issues.
There are other systems on the market that use cold plates and high capacity compressors, they cost many times more than a Mexicolder and then there is the install to pay for, so even if cost were not an issue, why wouldn’t I opt for one?
Cold plates are history, they are heavy, and they occupy the well-insulated box space you have supposedly created to store food in! They are problematic as most require expansion valves with mechanical connections that are prone to refrigerant gas leaks. Often they use a larger compressor and lots of associated and sophisticated control equipment to cool them so that means even more weight in batteries and heavy cables to supply the current. Add to this mélange the solenoid controlled valves, multiple wiring blocks, looms, suction accumulators and suction control valves………so much more to go wrong. Ask Nigel Calder.
What about engine driven systems?
In our opinion they are history too. From their first introduction and our personal experiences they were one of the most problematic systems we ever had or have worked on. In short, the operating pressure of the compressor at the end of the cycle is lower than the compressor was designed for in its role as an automotive air conditioning system. This often causes problems with the shaft seal and the system can get shut down due to moisture entering past the seal. The other disadvantage is that you are literally bound to your vessel, as the engine must be started at least once a day. Say goodbye to extended inland trips.
Do you offer “ high tech” digital controls?
No, the simple thermostat does a great job and is trouble free. If you insist, yes, we can custom install all the “bells and whistles” you desire, however we will put a switch in the system so that if you ever get hit by lightning, have a power surge or the digital control gets knocked out by your h.f. radio transmissions you have the option of having a simple, reliable thermostat.
Why is a high capacity compressor that I see advertised, advantageous?
It is not, as heat moves very slowly, and even more slowly as the temperature drops.
1.Think of your fridge box as the bilge and the fridge system as a bilge pump and the bilge water as heat.
2. If you had a lot of water leaks into the bilge you would want to stop them, this equates to building a well-insulated fridge box, thus stopping heat leaking into the box.
3. If you have a well-insulated fridge box, you have a smaller heat leak into the box and so you need a smaller more efficient pump (fridge system) to remove it at a regular interval.
4. Try sucking a cup of water out of the bilge with a 1 ½” hose size pump, then try with a ¼” hose size pump and you’ll understand.
We need both a fridge and a freezer; do we need to buy two units?
No, in almost all cases if the boxes are next or near to each other the cold air that spills over from the freezer box will keep you drinks ice cold and veggies fresh and crunchy. We built a custom system that use a small circulating fan and insulated 2” pipes to cool an auxiliary box when the boxes are split either side of the galley range like on the Catalina 42 “Ceilidh”, this works very well, the information can be found on this blog.
Assuming we purchase and have you install a system, what happens if we need spare parts in New Zealand or somewhere else on our circumnavigation?
All the moving components in the system are available in any developed country anywhere in the world. The system was designed with this in mind, we have been there! We offer a cruisers spares package for those going further a field. The key to the energy efficiency of the system is engineered within the static internal design features.
Where did the Mexicolder system come from?
An ANSWER to SATISFY hundreds of sailors who, over the last 31 years worldwide asked us “why can’t I have a boat fridge system as reliable as a domestic fridge/freezer?”
Good QUESTION…why not?
We took a blank sheet of paper and years of hands on experience. Then we wrote down all that was good and all that was not good of all the systems available on the market in the mid 1990’s. We kept the good stuff and then tested and tested and tested aboard a cruising sailboat in the severe heat conditions during several summers in the Sea of Cortez Mexico. We then removed all the excess moving parts that were “fluff” but doubled up on the stuff that kept the compressor or “heart of the system” beating nicely. Then we chose the finest quality materials to build a simple, lightweight and efficient answer to the sailor’s needs and dreams.
Where can I have a Mexicolder installed?
At the time of writing in Mazatlan Mexico during the months October through May and during the summer in and around the Sea of Cortez, we have all the equipment and tools to install anywhere!. There are independent contractors who can make box modifications, or all the materials available to do it yourself. Check out " Building a box" later on posts.