Water temp vs. engine room temp...

[CliffA]

Since this is the first winter we have had our 340 I wanted to understand the affect of the lake water temp on the temp in the engine room when a boat is left in the water during the winter...I want to understand exactly what needs to be done regarding winterizing the boat in this area (Charlotte, NC) to avoid freeze damage....I came across this post that involved several years of tracking the correlation between water temp and engine room temp....this study indicates the engine room temp usually stays within 5 - 10*F of the water temp...this assumes the engine room vents are plugged to keep the air stagnant inside the engine room....this is somewhat comforting since the water in our lake rarely falls below 40*F from what I am told...I have an Xtreme bilge heater installed in the bilge just in case it is needed....

http://www.wayneswords.com/index.php?option=com_kunena&Itemid=27&func=view&catid=5&id=22564

cliff

 

[Wylie_Tunes]

Ive been boating on Wylie, Norman and Mtn Island since 1995. By boating, i mean skiing, wake boarding and wake surfing year round. I have never found the water to ever get below 50*. A good buddy runs a large marina on Wylie. They have 3 covered docks, so 6 rows of slips. Id say 60 of the boats are in the water and freezing is not an issue.

 

[The Bill Collector]

We keep our boat on Puget Sound which is around 50* in the winter and few degrees warmer in the summer.... I have block heaters on the engines now, but before I put those on I would keep a DRY AIRE plugged in during the cooler months.

 

[northern]

I have my boat near Nanaimo on Vancouver Island. Some times the water surface freezes over and some times we get 6" of snow. I have two 100 watt heaters on the boat. I leave the battery charging system on all the time. Ten 6 volt batteries and four 12 volt. It has a water maker and 8KW generator. I have no heater in the engine room. I leave 100 gallons of water on the boat over the winter because the marina turns off the water to the boats. Some times I go to the boat and work on things. I have never had any thing freeze. Temperature normally is near or just below freezing for January and February. Lowest is -10c or about 20f for a few days then arms up to above freezing.

 

[sdarc]

Cliff, When I had my boats in Norman over the winter I would winterize the HVAC, water and waste. kept a bilge heater just in case and a small ceramic heater in the cabin. I also had a thermometer in the engine rooms and cabin that would record the highest and lowest temps. That was more peace of mind.

Fortunately, the winters I kept the boat in were mild. Not like last year and what is coming tonight and tomorrow.

 

[JimT]

LKN water temp is 49 right now. It will increase a bit with the sun today. Even with the predicted temp of 12 tonight it won't go below 45 over the next few days.

 

[BillK2632]

I don't know exactly what the effect of a boat sitting in relatively warm water is - I know it has a big effect vs a boat sitting on a lift or trailer. Also, an open slip vs covered is also a big difference - amazing how much everything heats up in the sun even on a cold day. That said, my 290 that stayed in an uncovered slip on LKN year around, I kept a BoatSafe heater in the engine room, stuffed some foam in the vents and left the Cruisair on heat at 55deg. When I knew it was going to be cold I would drain the faucets in the cockpit sink and transom shower. Only thing that ever froze was the transom shower. There is a point and I think that is in the low teens that the air temp is simply too cold and even a boat sitting in warm water is going to start having things freeze. I never heard of an engine block or risers freezing and cracking on any of the large boats in my marina. But I did hear about a big SeaRay that sank at a private dock on LKN - the only think the owner had done is left the Cruisair running (no ER heater, nothing else) during a really cold snap the discharge from the Cruisair system froze, popped the line off of the thru hull and the unit continued to run pumping water into the boat. It basically sank itself. Now, a boat on a trailer or lift is a different story - you really need to winterize it. My bowrider used to stay at our lake house on a lift, I kept my boatsafe heater in it - after a cold snap like we are about to have, went down (Lake Tillery) to check on things and found the breaker popped and the heater not running - temp in the ER was 20deg and the water in the block and risers was frozen. I got the heater going and thawed it out, luckily no damage, but after that I started at least draining the engine during Jan/Feb. Now the boat is in a dry stack, I just throw in the towel and winterize around Thanksgiving until March - no access to power or anyway to keep things warm. But I've been known to take it out in Feb on a warm day and then winterize it again! I wouldn't even consider winterizing a larger boat that stays in the water in our area - too much good boating in the winter time.

 

[CliffA]

thanks for the replies....we are using the boat on WE's through the winter so i don't want to do any more winterization than needed....i called the maina yesterday and spoke to the manager....she told me she could not remember ever having a wet slipped boat having freeze damage but they did have several stacked boats with freeze damage due to no or improper winterization by the owners....i asked the manager to send a mechanic down to the boat this morning just to verify the bilge heater is working and to check everything out needed to get through this frigid weather moving in...the bilge heater is low in the bilge and i could not get this old body contorted enough to test it with freeze spray....having the mechanic look at things is more just for piece of mind for me since this is the first winter with the 340 and the unusually cold weather coming in...after this year i will have a better feel for what needs to be done for future winters....i do have a full fresh water tank and full hot water heater and the waste holding tank is about 1/4 full....i have left the HVAC heat set at 55*F in the cabin and i have full camper canvas installed.....i allso used some car wash sponges to stuff in the engine room vents...since the wet slip is covered the boat will not build heat directly from exposure to the sun during the day....it will be interesting to hear what the mechanic has to say as to what (if anything) else needs to be done to protect the boat....

cliff

 

[Southpaw II]

I have used Boatsafe bilge heaters in 3 boats, from 29 to 38 feet; both in the Pickwick area of North Ms and here in the central part of the state. I gets cold here, but normally doesn't stay cold long. The only freezing I have experienced has been the shore water inlet, and once, the plastic bilge pump check valve in the aft part of the ER. I have learned that the coldest part of the ER is the most rearward, and now that's where I have positioned my ER heater, with no more issues. If it gets below freezing, and doesn't get above freezing during the day, there is a possibility of the Crusair system freezing at the water outlet on the side of the boat. Even when our marina lake froze, the Crusair continued to operate until the outlet froze. So...the air temperature is what shuts you down first. It's expected to be in the 14-16 degree range here tonight, with a high tomorrow of about 33 degrees. I'll go by the boat this afternoon and add a space heater to the cabin, just to supplement the Crusair unit.

Don

 

[CliffA]

If it gets below freezing, and doesn't get above freezing during the day, there is a possibility of the Crusair system freezing at the water outlet on the side of the boat. Even when our marina lake froze, the Crusair continued to operate until the outlet froze. So...the air temperature is what shuts you down first. It's expected to be in the 14-16 degree range here tonight, with a high tomorrow of about 33 degrees. I'll go by the boat this afternoon and add a space heater to the cabin, just to supplement the Crusair unit

using a space heater to supplement the HVAC system is an interesting idea....i thought i remember reading in the HVAC manual that the system should work well until the water temps gets to around 40*F as far as its ability to pull heat out of the water and into the cabin....our lake water is around 50* right now....but i think you are speaking about the through hull freezing that discharges the water from the HVAC overboard.....i am a little confused on how adding a space heater inside the cabin can help keep this fitting from freezing any more than the HVAC system as long as the HVAC is still putting out heat into the cabin....i am not doubting that it does help, just need a little help to undertsand how...

would it help if the water line from the HVAC unit to the through hull fitting was insulated?...

another question about using a space heater along with a bigle heater.....i have the bilge heater plugged into one of the AC power outlets in the cockpit being fed by shore power....the space heater in the cabin would also be plugged into an AC power outlet inside the cabin also fed by shore power...if both heaters happen to be activated at the same time would that trip the 'AC Outlet' breaker?.....if so that would render both the bilge heater and the space heater inactive...

thanks....
cliff

 

[sdarc]

Cliff, I wouldn't rely on the HVAC to do it's job. It is not going to heat the low areas and places behind the walls and cabinets. That's why I did my systems. Your at the Boat Rack? Covered slip? if so you get little/no solar help. I don't know how deep it is there. The end of Rocky Creek has had a skim coat of ice in the past. Last year? Also at colder water temps increases the chance the evap. core to freeze up. There are some threads on here about that happening.

 

[CliffA]

Cliff, I wouldn't rely on the HVAC to do it's job. It is not going to heat the low areas and places behind the walls and cabinets. That's why I did my systems. Your at the Boat Rack? Covered slip? if so you get little/no solar help. I don't know how deep it is there. The end of Rocky Creek has had a skim coat of ice in the past. Last year? Also at colder water temps increases the chance the evap. core to freeze up. There are some threads on here about that happening.

thanks Steve...it may be worth the $100 or so to get one of the marine ceramic space heaters from West Marine and put it in the cabin this afternoon....

cliff

 

[JimT]

Cliff,

My bilge heater is hard wired to one of the accessory breakers on the main panel. If you have an unused breaker you should consider rewiring.

If you recall exactly a year ago we had a cold snap with temps in Charlotte down to 6 overnight. My boat and the others on my dock did fine with the bilge heater and reverse cycle heater. None of the larger boats at PYC winterize and none had any freeze damage last winter which was the coldest in recent memory.

 

[Southpaw II]

If you use the space heater, open the head door, and the galley cabinets below the sink to allow those areas to heat. No, the space heater will not prevent the discharge from freezing, but is a bit of insurance if the Crusair unit freezes and shuts down. When the Crusair units cycles off, the water drip down the side of the boat freezes in the cold air, and then every cycle it grows until it gets stopped up and shuts down the unit. My bilge heater is wired to the power inlet on the boat, and I plug my space heater into another leg, so as to split the load. Also, my space heater has a thermostat and a setting that I leave at about the mid-range.

Don

 

[sdarc]

Another thought is when there are ice storms. None predicted for this go round but if power is off have to have a plan for that. Duke works down the distribution ladder. So I don't know how far down the grid you are. At Skippers we were along the main feed from Marshal Steam Station. My dock mate worked for Duke and now does sub work for them with his own company. That's how I learned this. I didn't stay at a Holiday Inn Express.

 

[sdarc]

Just some more thoughts and opinions: http://clubsearay.com/showthread.php/69568-quot-Lite-quot-winterizing

 

[Woody]

My boat is not in the water during the winter months but here'd be my thoughts. I wouldn't run/rely on the boats Crusair for heat. When the water temps get low enough they are working hard to provide heat. I've been on my boat when water temps are around 40F, air temps below 30F and nothing warms up fast I can tell you. You also have the potential for frost up or discharge water freeze up that could cause problems like mentioned above. I'd play it safe and shut down the Crusair, winterize it and the water system, it's so easy to do.

I'd just run a bilge/engine room heater and for the cabin heat I'd put in a ceramic and a small desk top fan to circulate air around. I actually do use a ceramic and small fan in my boat cabin in the winter, I have no moisture/mildew problems at all. It does run up my electric bill but I see weeks of below zero temps each winter.

 

[vandal]

At my marina in NJ they just pulled the boats left in water for winter because it will be 5 on thursday morning. Drain water in fresh water lines just blow out lines or open all valves like shower out back and drain sink up top. Your heat will not make much heat over 45 put small heater in cabin.

 

[Do Over]

just for informational purposes I wasn't able to run multiple ceramic heaters without kicking the breaker last time I tried.

 

[Prosideus]

Middle TN with boat in the water. Have Extreme Heater in ER, and two radiator heaters in the cabin. One forward and one in galley. It is important to have plain switched heaters, and not electronic controlled heaters. Reason being is that if the shore power goes out, the plain switched heaters will come back on because the switch remained on, where the electronic heaters reset to off. Down to 5 degrees tonight. Considering spending the night on the boat just for peace of mind, but haven't totally decided yet.


Sent from my iPhone using Tapatalk