A Heated Conversation
We occasionally get asked whether it is possible to run a reverse-cycle marine air conditioner (heat-pump) when the water surrounding the boat is at freezing temperatures. The answer to that is “yes, it is indeed possible”, but is it a sensible, safe, and reliable way to heat a boat in those conditions?
Most of these inquiries come from live-aboards up north, although we may well be hearing from some in Florida and other southern states in the days to come once this arctic blast hits down there also. We hear that many marinas are now stipulating that plug-in heaters are prohibited, citing insurance issues, including even the ceramic and oil-filled radiator types, which seems a little overly precautious to my mind.
For a really cozy cabin you could install a diesel-fired forced air or circulating water system, but these are expensive and complex installations that require strict adherence to the manufacturer’s instructions in order to prevent potential ventilation, exhaust, and noise issues. Then, they sit idle for half the year.
So, your vessel is sitting in freezing/frozen water and you want to use your reverse-cycle air conditioner to heat the boat. You won’t get that much heat out of it, but once it’s up and running and you have a warmish cabin, you should get around 30F higher air temperature at the air outlet than at the inlet. Just don’t stop it once it has started, as it will take forever for the system to start producing any useable heat again. A cold compressor will suck up all the heat being produced by the system for the first 15 to 30 minutes until that heavy hunk of metal has had a chance to heat up.
Are you, or is anyone you know, a Temperature Control Freak? You know the type; constantly fiddling with air conditioning and refrigerator controls and reporting on them to anyone within earshot. Well, I have such a friend.
TCF, as we will call him, has a digital temperature controller/thermostat and tells me that 39.2°F is the perfect temperature for his fridge. How he comes to this conclusion is beyond me, and quite honestly I don’t want to ask. Suffice to say that he’s happy with that after several months of laborious experimentation. And then there is the freezer ...
Now a fridge can only be between a narrow band of temperatures; too cold and it’s a freezer, too warm and it’s not a fridge. But a freezer can be kept at any temperature below freezing; from marginally frosty to cryogenic. It’s all down to how you intend to use it.
Foodstuffs will be preserved as long as they are frozen, but the appearance and edibility when thawed will differ with different temperatures and time. In Europe there is a star rating system for freezers as follows:
Under the Cover of Darkness
By necessity, this will be a truncated blog this week as my trusty laptop is going in for a hard drive transplant tomorrow so I’ll be on edge all day hoping the surgery was successful. My current C drive is 98% full, and it’s amazing how much storage solid state hard drives have these days. This little upgrade will obviate the need to replace the whole darn machine just to gain some breathing room.
I asked my IT guy for advice on the laptop issue and he came back with some options and a recommendation, which I duly followed. We at Coastal Climate Control endeavor to advise our customers on the best way to plan, install, and troubleshoot the equipment we offer and represent, but there’s always some folk that want to ignore good advice and go their own way. Why is that?
Here’s a good example, with a less-than-good outcome. My neighbor has a beautiful and probably very expensive Porsche, a real sporty beast all shiny and jet black. His house is at the corner of an intersection in our sleepy neighborhood, and he keeps it parked on the street and nearly always covers it in a matching black cover.
One night a year or so ago I came home driving our company Sprinter van, and as I turned the corner I almost clobbered the Porsche, hiding there in the dark under its black cover, having seen it only at the very last second. I mentioned this to the neighbor and suggested he put some reflective tape on the cover to hopefully prevent any future carnage, but my suggestion was shrugged off. No reflective tape materialized.