For the last two winters I have run one of these heater/fan units.
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I bought the other unit as well, because I didn't know any better.
Now our boat is in the water all winter and we have a covered but not enclosed slip.
The boat is welded aluminum with a cabin and I set the thermostat at medium high and it cycles on and off and keeps the boat at about 70 F.
I place the heater on the floor in the cabin and block the door to the V-Birth open . We always have the heater stored on the boat and have a few times when it has been cold or stupid rainy out run the heater at night when we were sleeping. We have a smoke detector and a CO detector.
The boat is plugged in at the dock and I know our monthly hydro increases in the winter with the heater running but the invoicing periods are never the same so I can't figure out how much more it costs to run the heater all winter.
I could work out the cost if I used the power consumption but in the end I would still be running the heater so it made no sense to just find out exactly how much more another item on a boat costs on a daily basis in the winter.
We use the boat year round and I can't tell you how nice it is to get into an aluminum boat that is warm inside from the get go. If we didn't have the boat warm from the get go it would really curtail the enjoyment of winter boating
We unplug the electric and turn on the diesel heater as soon as we get aboard and crack open one of the side and rear facing windows to insure fresh air flow while aboard.
I went to Michaels (with the heater) and found a plastic box with a snap lid to store the heater in.
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