Winterising merry fisher 805

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gordhouse

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I know this topic has been covered in previous threads and in reading them i think i have decided to place a tubular heater in the engine bay on a thermostat set at about 5 degrees. However i am not sure what to do on the fresh water side.
Do i just run the hot and cold taps dry then leave them open.
Drain off the colorifier (what is it and where is it) does it have a drain off tap?
 
gordhouse said:
I know this topic has been covered in previous threads and in reading them i think i have decided to place a tubular heater in the engine bay on a thermostat set at about 5 degrees. However i am not sure what to do on the fresh water side.
Do i just run the hot and cold taps dry then leave them open.
Drain off the colorifier (what is it and where is it) does it have a drain off tap?
Click to expand...

Definitely drain the domestic water.

In the four years that i've had my 805 i have turned the taps on until the water stops running and left the galley and heads taps open. Never a problem, except the first Winter when we were a little late doing it and the galley tap froze a bit, with no damage, luckily.

The calorifier is your immersion heater, if you like. It heats the hot water via 240v or the engine. It is located under the port side floor. You access it by lifting the table out, removing the four threaded screws in the "teak" floor panel (one in each corner) and the two front most wood screws in the base for the table leg. The panel then lifts out, giving access to the batteries, split charge diode and at the very rear, the calorifier. The calorifier can be separately drained, there is a ball valve and a pipe leading to the bilge pump sump in the lazarette locker. The system is pressurised though and i don't think there is enough water left in the calorifier to do any harm, after you drain the tank etc.

As an aside, in case you didn't know, the potable tank, water pump, filter and accumulator are located beneath the floor in the galley cupboard (beneath the sink). They are also accessible from an inspection hatch in the lazarette locker, held in place by two screws. Also in there with them is the shower and bilge pump and their filters. A particularly stupid place for the bilge pump filter, i'd like to be able to clean mine quickly if i was pumping a leak out and fitted mine with a second filter in the lazarette.
 
My boat is a Sealine but similar as far as this topic is concerned.

I drain off the water by running the taps until spitting the last few drops. I dare say this leaves a little water in the pipes. Taking care not to run the pump dry for more than a few seconds. Not forgetting to shake out water from any shower heads.

I did lose a shower head one winter - must have left some water in it.

The calorifier should have a drain cock near the bottom. Some water will be left in the calorifier after using the pump. Must confess I have not used the drain cock and my calorifier has survived some severe icy weather.

Engine room and saloon tube heaters or other low wattage heat are a good idea.

Some people block up the engine bay vents to keep a bit of warmth in.

I also use moisture traps (mine are from Lakeland) which are very good at keeping damp at bay. A moisture trap in the saloon and one in the mid cabin in my 25ft sports cruiser do the job.
 
as an extra precaution I put some Camco Winterban into the fresh water tank and pump it so it comes through the taps.Its not an 805 though.
 
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Does anyone fill the raw water system with an antifreeze mix or will tube heaters suffice ? ( I have an 80w in engine bay and 135w in the boat, set at 5 deg turn on)

I want to use my 805 over the winter and didn't particularly want to repeatedly pour anti-freeze into the marina........
 
countvonc said:
Does anyone fill the raw water system with an antifreeze mix or will tube heaters suffice ? ( I have an 80w in engine bay and 135w in the boat, set at 5 deg turn on)

I want to use my 805 over the winter and didn't particularly want to repeatedly pour anti-freeze into the marina........
Click to expand...

Neither of those tube heaters will reliably protect the domestic water systems. The calorifier is in the space between the engine compartment and the hull on the port side, the water tank, pump, accumulator and filter is in the space between the engine compartment and the hull on the starboard side. The 135w heater might protect the taps, but that's all.

We use our boat all year round, but during the winter we drain the domestic water and take some water with us.
 
PaulGooch said:
Neither of those tube heaters will reliably protect the domestic water systems. The calorifier is in the space between the engine compartment and the hull on the port side, the water tank, pump, accumulator and filter is in the space between the engine compartment and the hull on the starboard side. The 135w heater might protect the taps, but that's all.

We use our boat all year round, but during the winter we drain the domestic water and take some water with us.
Click to expand...

I have run the domestic water tank dry and left the taps open, more worried about the engine !
 
countvonc said:
I have run the domestic water tank dry and left the taps open, more worried about the engine !
Click to expand...

Don't be. Your coolant should be 50% antifreeze, which will not freeze in the UK, until the next ice age. The salt water in the raw water cooling circuit isn't likely to freeze. Mine has never had any heaters in the engine compartment in it's life, so yours should be more than safe with the 80w heater.

All assuming you are in salt water, not fresh water, or moored in Alaska.
 
Moored in Brixham, luckily not Alaska.

So are you saying it would be adviseable to drain the calorifier?

From your reply to the OP above I figured I should be ok with emptying the fresh water tank and leaving the taps open and sticking the tube heaters on.
 
countvonc said:
Moored in Brixham, luckily not Alaska.

So are you saying it would be adviseable to drain the calorifier?

From your reply to the OP above I figured I should be ok with emptying the fresh water tank and leaving the taps open and sticking the tube heaters on.
Click to expand...

if you have done that, the calorifier will be more or less empty.
 
Mike k said:
as an extra precaution I put some Camco Winterban into the fresh water tank and pump it so it comes through the taps.Its not an 805 though.
Click to expand...

Used Winterban last year. Worked OK but took several fill/empty operations @ 250 liter (+ some desinfection fluid) to get a bad smell out of the system in spring.
Not cheap either.
 
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Spi D said:
Used Winterban last year. Worked OK but took several fill/empty operations @ 250 liter (+ some desinfection fluid) to get a bad smell out of the system in spring.
Not cheap either.
Click to expand...

I know what you mean SpiD there is an after tangy odour which went after a refill for me too but i only use the FW for washing things and carry drinking water on board so didnt mind .
 
Mike k said:
only use the FW for washing things and carry drinking water on board so didnt mind .
Click to expand...

Same here. The smell was so strong that running the water even shortly made people rush out. SWMBO didn't want cutlery etc. to get in contact with it..

Got OK eventually but not going to do it again this year. Just drain and leave taps open.
 
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