Practical Boat Owner - January 2016

Great ideas and tips from PBO readers

Practical projectsEmail your projects and tips to [email protected] or write to us at the

address at the top of page 5. We pay at least £30 for each one published

Stu Davies maximises the effi ciency of his boat’s refrigerator on a trip to the Algarve by introducing a
low-cost computer fan to assist the cooling of the condenser

Keeping your cool
in balmy climes AROUNDCOST£4

Ochest refrigerator is fifriends’ wives on bigger boats are jealous of the one on mine! n my Bénéteau Océanis^381 Bénéteaus, a serious Sacha, as on most tted. My
gas, passing it through a condenser where the hot gas is cooled and turns into a liquid. This liquid is Fridges work by compressing
forced along copper pipes to the evaporator, which is the cold thing you see in the box. There is a restrictor in the pipe where it enters
the evaporator and a pipe going back to the compressor from the evaporator. The compressor sucks through that pipe against the
restrictor, which creates a low pressure in the evaporator where the liquid gas evaporates to cool the evaporator. Think about a gas
bottle when you use a lot of gas quickly; you can see a frost line on it where the LPG is evaporating. The same principle applies here.
Refrigerator effiThe compressor is under the sink in a cupboard with the waste bin. The condenser is also sited there, ciency
and relies on fan cooling to condense the hot compressed gases into a liquid that then goes to the evaporator in the fridge
compartment, where it evaporates to cool it. The refrigerator’s effidepends on the movement of air over the condenser: this is where ciency
the ‘warmth’ of the refrigerator is removed. If this condenser is dirty, or air cannot move over it effi ciently, then the performance of
the refrigerator is compromised. The compressor will run continually and the box won’t come down to temperature quickly.
down to the Algarve, the ambient This summer, as we took Sacha^

temperature was not too high on the way and the fridge worked well. However, once on the Algarve the ambient temperature went up,

and at one point it was 30°C in the saloon. The fridge was running continuously – not good for power consumption or the compressor.

The cupboard where the compressor is has a hole in the bottom, which has a blanking plate in it, and there’s another

hole halfway up for the hot air to exit. As a temporary measure while we had mains power, we opened the cupboard and

pointed a mains-driven fan at the compressor to help cool it down.that computers have nice, quiet, I knew from my previous work

12V cooling fans in them, so I decided to source one to pull air into the cupboard to help cool the compressor. I managed to fi nd an

80mm one that fithe hole in the bottom of the cupboard. These fans have arrow markings on them to indicate the tted nicely across

direction of airfl ow.

back of the condenser, cleaned the accumulated dust off the blades and condenser and also I took the existing fan off the

removed the existing stainless steel louvred plate off the exit hole to make it easier for hot air to exit the cupboard. I then spliced the wires

of the new fan into the existing fan wires, removed the blanking plate and screwed the new fan in place. When the cooling fan was running,

so was the extra cooling fan.performance was very noticeable: I was able to turn the fridge down I fi red it up, and the difference in

a notch and got it cycling at 5°C in the box with not too much running time!The fan cost r6 (£4.25) in the

local computer shop in Faro, and was easy to fifrom the bottom of the boat was cool because it was in contact with t. The air blowing in

the water-cooled hull and was deflthe waste bin. Cool air equals a cool condenser, which equals an ected up to the condenser by

effi cient fridge!

ONWARDS AND

UPWARDSLast spring, I bought Anne Marie – a 1977

Stratimer-built Endurance 35 ashore at Rye. On the outside she looks OK-ish, but on the inside things are

different. I reckon to have her back in the water in June 2017, and I thought I’d write in to demonstrate

a novel way of gaining access for the repairs as I really did not fancy climbing up and down

ladders for two years. Tenterden, Kent is Symonds Salvage, which specialises in Near to where I live in

house salvage and is a great place for a wander. I was looking for some quarry tiles the other day when I espied

an old wooden staircase: a reasonable price was negotiated, and within a week I had a very practical and

easy-to-use means of access onto my boat. It’s amazing what you finot looking. nd when you are

renovation in a blog, https://savingannemarie.wordpress.com/tag/anne-marie – so if I am writing about the

any readers want to follow my progress or indeed offer advice, all they have to do is follow the link.

Mike Stephens

An 80mm, 12V computer fan now helps to cool the condenser