what temp to set it at

[lanerboy]

hi all

i have purchased a few thermostically controlled plugs i am going to be having one run an oil filled radiator in the engine bay over the winter

my question is what should i set the temperature at for the radiator to kick in, i was thinking 2 degrees obviously i dont want it to freeze but i also dont want to run up a massive electricity bill keeping the engine warmer than they need

what do you think it should be set at

cheers shawn

 

[rafiki_]

I set mine at +5c. This gives a bit of wriggle room if the temp is dropping quickly. I have 3 tube heaters, 120 watt each, 2 in the engine room, 1 in the cabin. I cover the engines with a sleeping bag. I get rid of all the domestic water and empty both holding tanks. No problems down to -19c a couple of years ago. You should be better off at Weymouth, as the sea water will be a higher temp than the stationary water where Rafiki lives.

 

[andy59]

Have set mine to 5 degrees to be on the safe side , no problems so far on 2 boats .

 

[lanerboy]

thats interesting i was too low then weymouth will be better than the river Raf but will air temp still be about the same???

will be putting the heater in between the engines and temp sensor plug over on the side of the engine bay

 

[Scubadoo]

I set my plug thermostat to +6c, like the others have said, that gives it time to switch on and heat the engine bay as the temp continues to drop.

This was asked last year, and others have set to +4c.

 

[PaulGooch]

Never had the engine freeze yet, 50/50 antifreeze doesn't freeze very well. The salt water in the raw water cooling circuit doesn't seem to freeze too well either. The fresh water system did freeze once, luckily not causing any damage, we meant to drain it, but the cold weather got it first.

We drain the domestic system and put a tube heater on a timer in the bow cabin, with the door open, to come on 8 PM to 8 AM to stop anything getting damp. With a bigger boat i'd fit more tube heaters in the cabins. We didn't do this the first year and the boat always felt really cold when we arrived in the Winter.

Genuinely curious, what is it that everyone seems to think will freeze in the engine room if the temp gets to 5 degrees ? Can understand it for those in fresh water or those on the hard, but not for boats in salt water ?

 

[oGaryo]

+3 degrees when I used to have my boat on a trailer so in the water, I'd imagine you can get away with less.. also, the air temp in the engine bay may drop below zero momentarily whilst the heaters kick in but it takes hours for the water / coolant in the engine waterways to feel the effect and by then, the air temp will have increased.

I'd use one or two mini oil filled rads rather than the tube heaters in an engine room the size of yours, they'll kick out more heat in less time and still be safe (no fan, sparks etc)

 

[PilotWolf]

thats interesting i was too low then weymouth will be better than the river Raf but will air temp still be about the same???

will be putting the heater in between the engines and temp sensor plug over on the side of the engine bay

I was going to say make sure the plug is close enough to the heater that it senses the temperature increase or there is a serious risk of over heating.

W.

 

[sailorman]

hi all

i have purchased a few thermostically controlled plugs i am going to be having one run an oil filled radiator in the engine bay over the winter

my question is what should i set the temperature at for the radiator to kick in, i was thinking 2 degrees obviously i dont want it to freeze but i also dont want to run up a massive electricity bill keeping the engine warmer than they need

what do you think it should be set at

cheers shawn

what do you have under the car engine that stands outside

 

[David of Essex]

One added advantage of having a small heater in engine bay, is with modern engines that have more electronics it help to keep these items dry.
David

 

[Thepipdoc]

I don't use heating of any sort when I'm not onboard.
The boat stays in the water and we use it every weekend and occasionally during the week. Out of curiosity, what are your electric bills like when you do have heating coming on when its gets cold?

 

[Deefor]

AFAIK, most mechanical type thermostats on any type of electric/oil radiator have a tolerance of perhaps +/- 2 degrees or more if the heater is a cheapy model. So setting a rad to 5 degrees could mean it cuts in and out from anything to 3 or 7 degrees .

 

[ontheplane]

How about 2 heaters, a really really low powered one (35W greenhouse perhaps) set to come on at 6 deg, then another one with a more powerful heater (small oil filled) set to come on at 2deg??

Just an idea...

 

[Ripster]

FWIW mine are set at +2 in the water (Salt Water). But for the short time the boat is out they go to +5 to give the heaters a chance to get going. As most will know temps inside the boat will fall lower and more quickly when not heated by the Sea.

 

[rafiki_]

what do you have under the car engine that stands outside

The car engine has a sealed system full of antifreeze. The heat exchanger is air to water, not water to water. I don't have taps or a calorifier in the car, nor any holding tanks. Do you?

 

[dkm]

You've done the right thing minimising the risk of any freezing. First of all spend £10 and get yourself a minimum/maximum thermometer from B&Q that will record the minimum temperature in your engine bay. Second, set the switch to 'on' at about 5 degrees. The most commonly available thermostatically controlled switch is notoriously inaccurate despite what it says on the packaging. 5 degress could be zero, and hence potentially damaging. This is where the min/max thermometer comes in, monitoring it will give you confidence that your switch is activating the heater(s) appropriately.
Assuming you will stay afloat through winter don't forget to drain down transom shower head and windscreen washers

 

[sailorman]

The car engine has a sealed system full of antifreeze. The heat exchanger is air to water, not water to water. I don't have taps or a calorifier in the car, nor any holding tanks. Do you?

Fair point

 

[matt13]

Last winter I bought the ET05 thermostatic plug and a max/min thermometer to monitor it. My boat is kept on a drystack so open to the elements. I had one tube heater in the engine bay and thermostat was set to come on at 4 degrees, the lowest recorded temp all winter in the engine bay was 1.4 degrees, so it did work, but probably does take a long time to heat up, this year I will set it to come on at 5 or 6 degrees just to be safe.

 

[lanerboy]

what do you have under the car engine that stands outside

nothing but i use my car daily but the boat i live 240 miles away and it will possibly left for weeks at a time over the winter

 

[rafiki_]

Last winter I bought the ET05 thermostatic plug and a max/min thermometer to monitor it. My boat is kept on a drystack so open to the elements. I had one tube heater in the engine bay and thermostat was set to come on at 4 degrees, the lowest recorded temp all winter in the engine bay was 1.4 degrees, so it did work, but probably does take a long time to heat up, this year I will set it to come on at 5 or 6 degrees just to be safe.

The ET05 stat plugs are great when they are working, but not the most reliable things in my experience. If I don't keep them charged up over the summer, their internal gubbins fails and they become decoration. The manufacturer is really good and has replaced all the failed ones to date. So it is worth checking that they are working ok before you rely on them in abstentia.