Winterising a Merry Fisher 805?

Steve 1

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i live in Cornwall so it normally doesan't get that cold during the winter Months! and we intend to use the 805 throughout the winter. I have got two tube heaters in the engine room would this be enough? any advise would be appreciated.

Thanks
Steve
 
i live in Cornwall so it normally doesan't get that cold during the winter Months! and we intend to use the 805 throughout the winter. I have got two tube heaters in the engine room would this be enough? any advise would be appreciated.

Thanks
Steve

Yes more than enough, as the sea temp is higher than the ambient air temp and the boat hull will remain warmer whilst afloat!
However the domestic water in taps/shower etc will need draining...Rob.
 
Thanks for that Rob, would i need to do anything with the Calorfier, (immersion) or would the tube heaters be enough. Steve
 
Thanks for that Rob, would i need to do anything with the Calorfier, (immersion) or would the tube heaters be enough. Steve

If its in the engine bay then I would suspect it be fine,however if you do drain the domestic system then I'm guessing that would also be drained?

Expect a few more replies here from member's who'll have the exact answer though.
 
This is just in my humble opinion...

1) I am not too keen on tube heaters in the engine room when you are in the water ... basically, heating the air in there will lead to more condensation (cold engine, hot air rising) ... as you probably will draw in cold air from intakes ... (you ought to block them if you want to avoid that)... condensation forming is not good for el connections etc. I'd be happier if the air and engine was same temperature (ie sea temp ... or close to...)
2) Calorifier ... yup drain that one as well as the other part of fresh water system(separate valve at bottom of unit)
3) Close off all air intakes in cabin, put a small oil filled radiator in fwd cabin and put on temperature controlled "timer" ... approx. 4 deg C ... but do not aim to heat boat
4) Put a de-humidifier on timer ... sort of 2 hrs / day at hottest part of the day ... let's say 14 - 16:00 ... or 15 - 17:00 (as air heats up, you it will hold more humidity)
5) Take home the soft furnishing you won't use
6) WD 40 or equivalent protective stuff for El connections etc.

Enjoy winter boating !!
 
You will defo need to drain the water system down and calorifier, it is located on the port side under the floor in the midships, there is a plastic drain bung on it that will drain the water off into the bilge, and leave all your taps open, also make sure that the shower sump drain pump has antifreeze mix pumped through it.
How long have you had there 805 and where did you buy her from ?
 
I have had the boat since April, i got her from Hartlepool. I was told that when i leave the boat for a week or so during the winter all i need to do is switch off the water pump and open the taps and leave the calorifier switched on. I have also got two tube heaters set a 5 deegres, i am also getting a Meaco DD8L dehumidifier. I dont want to completely winterise the boat because want to continue to use her. I don't know how expensive it is to run the calorifier all of the time, any advise would be appreciated. Steve
 
I don't think it is necessary, or safe, to leave the calorifier switched on all the time. Apart from the expense which could be significant over a few months. If you drain all the water as others have said, then the calorifier won't have any water to heat.

Or did you mean leaving the dehumidifier on all the time? If so, you should be aware that these only work in a warm(ish) atmosphere. So, you need some background heat. The tube heater would be fine.
 
If I empty the main water tank and turn on the tap in the hot position with the pump on would this not empty the calorifier?
 
If I empty the main water tank and turn on the tap in the hot position with the pump on would this not empty the calorifier?

Well it is a good idea to do that as it will clear most of the water from the system. BUT, to empty the calorifier you need to find the ball valve that controls the drain pipe near the bottom of the tank. This is normally shut, and is only there specifically to drain the tank. I would suggest:
1. Turn on the cold taps to let the pump get out as much water as possible.
2. Turn on the hot taps to do the same
3. Leave all taps open (switch off pump supply now)
4. Locate the ball valve lever on the calorifier and open it to allow the last of the water in the tank to drain into the bilge.
5. Pump out bilge

Please PM me if you need any more info on an 805 and I'll help if I can.
 
If I am using the boat in the winter and I don't fill the water tank so therefore the Calorifier is not filled. When you are running the engine it heats the hot water, so do I need to turn something off to prevent damaging to the Calorifier
Steve
 
If I am using the boat in the winter and I don't fill the water tank so therefore the Calorifier is not filled. When you are running the engine it heats the hot water, so do I need to turn something off to prevent damaging to the Calorifier
Steve
It won't cause any damage running the engine with the calorifier empty but if you are worried about it then just close off both the ball valves on the in/out circuit from the engine water to it. These are located under the floor that supports the saloon table. You should be able to get access through the inspection cover that just lifts off.
 
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