Staying warm on boat in the winter

ryno1234

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I'm planning on being part of an upcoming lighted boat parade, however temps are likely going to be 50 degrees or so, quite cold in my opinion.

We have full canvas (not sure of the proper term) where the cockpit area is fully enclosed, but what is the best way to stay warm?

We have an inverter and 3 batteries, but will also be running our running lights on along with a set of Christmas lights around the boat, etc. so I'm not sure how stressful an electric heater would be on the batteries. The only other alternative I could think of would be a propane heater, but that just sounds like a bad situation all around, so nixing that idea.

Is it too much to ask of my batteries to handle an electric heater, led charismas lights and standard accessories on the boat?
 

Chris1956

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Gee, 50*F is not real cold. How about a warm coat, gloves and long johns?

I would expect an electric heater in the cockpit on low would work. Your alternator should put out 65A or 780watts, at cruise speed, somewhat less at idle.. A typical heater is no more than 1500watts, so setting it on low probably works. Make sure your inverter can handle it, and the batteries will likely run down a bit, unless your motors are run at cruise speed.
 

Dubed

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If using a propane heater such as a Mr Buddy, mount it to a piece of plywood or similar and fix it the the deck so it cant move or slide. Be smart about location and what you put near it or around it, and always have a fire extinguisher. 50 degrees is not very cold, buy an electric sweatshirt, keep your feet warm and layer up. Use hand warmers.
I fish till its in the 30s and can normally stay fairly warm. I also lived on a boat for 4 years (summer and winter) in Rhode Island and stayed warm, but having heaters when youre docked isnt the same a when youre under way
 

ryno1234

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Gee, 50*F is not real cold. How about a warm coat, gloves and long johns?

I would expect an electric heater in the cockpit on low would work. Your alternator should put out 65A or 780watts, at cruise speed, somewhat less at idle.. A typical heater is no more than 1500watts, so setting it on low probably works. Make sure your inverter can handle it, and the batteries will likely run down a bit, unless your motors are run at cruise speed.
You're right. 50 doesn't sound bad to most I'm sure. I have a disease (Reynaud's). When I get cold, I can't heat myself up any longer. If it's less than 70 degrees (and I have no sun) my body starts to get continually colder and it accelerates. I have to have outside heating sources (hand crackers are awesome).

It's real lame, lol. 50 degrees sounds awful to me.

Good to know about the alternator output. If I knew more about how to calculate the electrical demand and the entire electrical system I could probably answer all this myself, but that is an area of knowledge I'm not terribly familiar with.
 

Scott Danforth

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We used to go boating with temps in the 20's and 30s.

Here is the rough rule of thumb

50s. Sweatshirt, wind breaker, sensible hat and gloves. May consider socks

40s. Jacket, heavy shirt. Heavy socks, good hat, gloves

30s. Snowmobile suit, or winter jacket and ski pants, heavy socks, insulated boots, gloves, ski hat

20s. Snowmobile suit, thermal underwear, electric socks. Hand warmers, mittens, scarf, ski hat

Unless you have a pilot house, a heater will just be a source of ignition for a fire
 

ryno1234

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Dec 8, 2014
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We used to go boating with temps in the 20's and 30s.

Here is the rough rule of thumb

50s. Sweatshirt, wind breaker, sensible hat and gloves. May consider socks

40s. Jacket, heavy shirt. Heavy socks, good hat, gloves

30s. Snowmobile suit, or winter jacket and ski pants, heavy socks, insulated boots, gloves, ski hat

20s. Snowmobile suit, thermal underwear, electric socks. Hand warmers, mittens, scarf, ski hat
Your 20-30's are my 50's. But I do like the breakdown! And, that's pretty awesome that you'd enjoy your boating down to 20-30 degrees. Good on you.
 

Scott Danforth

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Your 20-30's are my 50's. But I do like the breakdown! And, that's pretty awesome that you'd enjoy your boating down to 20-30 degrees. Good on you.
There are no ice chunks to avoid or the need to use a chain saw to cut a path to the dock in the 50s
 

Pmt133

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I don't even throw on the wetsuit on the wave runner in the 50s. But I understand the condition as far as you're concerned.... So all kidding aside... They have nice heated jackets but since you have the headroom... why not just an electric blanket over sweat pants/jacket. That should suffice and not draw a terrible amount of power either.
 

alldodge

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I don't know of a way that wouldn't cost a bunch or be noisy, both would use a 400 watt electric heater. Don't know how long power will be needed

Noisy - Get a 1000 watt gas Gen (under $200) and place it on the swim deck

Costly - Get a LiFePO4 Battery ($1000) to power the inverter, don't use the Boat motor to charge the Bat
 

racerone

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A sterndrive ?-----Get a heater hooked up to engine cooling system.-----See your dealer.
 

QBhoy

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Hi...so this is something that I and an almost uncountable number of other boat owners are very well versed with...just from living and boating in Scotland. I won't need to tell you all, that Scotland has a climate almost like no other on the planet. We can literally see 4 seasons in one day...being serious. a couple of times per year, at the end of the season, the temperature has been known to vary by nearly or even 20oC, within less than 24 hours.
So...the ability to introduce some means of heating in an efficient way was devised and now hugely utilised in most boats over a certain size. It is absolutely a very common thing here.
The way this is achieved, is for the boat to have a diesel fired blown air heating system. Most common and numerously fitted over the last few decades, would be either an Eberspacher or Webasto brand unit. These were originally mostly used in lorry or truck road vehicles to heat the cab. Then frequently fitted in motorhomes and camper vans. Very efficient things and if fitted properly, very safe too.
They basically have a fan in the unit that can suck air either from externally or from the space you are trying to heat. Then the air is heated by means of passive exchange from what is basically a small diesel fired furnace inside the unit, then blown at a positive pressure through flexible ducting (that runs a route up the side of the boat hidden away) towards a directional outlet that is located in key areas like the cockpit, cabin and basically all around the boat. Temperature is controlled and regulated by a small digital mounted remote unit or even by remote control or from as far away as your house, via a SIM card remote activation.
There are now a number of cheaper alternatives available, other than the big two mentioned above. Just as good a quality too. Like Planar etc etc. The main thing is to ensure it is safely fitted with proper fittings and exhaust parts. I couldn't do without mine. Have a look online. Very easy to install yourself too, if you have a basic mechanical mindset. Look up Eberspacher D2 or D4 marine heater. the most expensive brand no doubt, but they can be bought for as little as a couple of hundred quid too.
 

ryno1234

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Thanks everyone for your input! Definitely helpful.

So, very much related - I want to test run my accessories on my batteries while at idle to understand what the drain is on the batteries.

What is the best way to do this?

I'm taking a shot in the dark with this logic, let me know if it checks out: If my battery reads 12.6v through my multimeter at rest and then I start the boat and turn on all my accessories, lights, etc. and my battery terminals shows *at least* 12.6v while running, does that mean that battery is not discharging because the alternator is keeping up?

I know typically the terminals, with the engine running, will show something like 14v, my hack logic was wondering if we're at least staying up the initial resting volts of 12.6v, are we good and the alternator is making up for my draw?

To take it a step further, if we're not keeping up and the batteries are discharging, is there a way to reasonably measure that discharge rate?

I can start a new topic if this isn't straight forward.
 

redneck joe

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Never hurts to start a new thread in the specific forum as you prob will get better and more answers. When you do post the link here with a brief explanation. That way this thread is an over arching one about heating but will also have the many side roads we take on our boat project. In the future if someone like you who reads a lot before posting happens upon it, it become a core complete possible answer for their project.
 

dingbat

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I want to test run my accessories on my batteries while at idle to understand what the drain is on the batteries.

What is the best way to do this?

I'm taking a shot in the dark with this logic, let me know if it checks out: If my battery reads 12.6v through my multimeter at rest and then I start the boat and turn on all my accessories, lights, etc. and my battery terminals shows *at least* 12.6v while running, does that mean that battery is not discharging because the alternator is keeping up?
No...testing needs to be done live.

Take voltage reading with battery fully charged and motor running. Then flip on your load.

If you don't get an immediate voltage drop, demand and supply are roughly balanced. If the voltage drops over time, you have an unbalanced load and the excess is coming off the battery storage.

At that point, consumption can be calculated using the rate of drop over time. Bear in mind that starting and deep cycle have different discharge rates. A starting battery doesn't buy you much time
 
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froggy1150

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You can also try throwing an ammeter on the main feed to the boat ( not to high draw starter)
 

rallyart

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Perhaps you have to little time for this, but installing a Heater Craft system is very effective. Not as good at idle in a sterndrive as they are in an inboard due to plumbing possibilities. I've got two 40,000 BTU units hooked up in series on my boat.
For an immediate and cheap heater, get a propane camping heater. Just make sure you have ventilation. CO is not what you want in a closed space.
 

Chris1956

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If you want to add heat to the boat permanently, it can be pretty easy to rig up.
Go to a junkyard and get a heater core from some junked auto.
Build a wooden box to hold a 12VDC fan and the heater core. You will need some sort of decorative gratings to let the heat out and air in.
Install the box in the cockpit and wire the fan to a switch or rheostat.
Use some heater hose to "plumb" the heater core in series with the hot water of the engine. The output of the thermostat is a good spot to get hot water. Run this to the heater core, and back to the manifolds.

Warm up the motor and turn on the fan. Enjoy the cruise. Remember to drain the system when you winterize the engine.
 

dingbat

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I'm The only other alternative I could think of would be a propane heater, but that just sounds like a bad situation all around, so nixing that idea.
Not a bad idea at all.
They make radiant heat propane heaters suitable for use in this application

 
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