240V fridge freezer and heating

[Dibbo]

Hi Guys, looke at a boat today with view to live aboard, ticked many right boxes, but it seemed to have a 240 v fridge freezer. Now it has a 3KW Mastervolt inverter, 3KW Vetus generator and 4 leisure batteries . I presume the fridge runs off all the power available, but when we're out, how long are the batteries going to last with a medium sized F/Freezer running?. The 240v hook up will be fine whilst at mooring.

It has a bubble diesel stove running 2 rads. I presume via a small pump. Are these economical to run? would it be possible to replace with a solid fuel stove and a seperate heater........ Questions i should have asked the vendor but never thought at the time.

cheers,

Dibbo

Edited May 29, 2011 by Dibbo

[WotEver]

... when we're out, how long are the batteries going to last with a medium sized F/Freezer running?.

Not very long. You need to do a power audit. Just below half-way down here: http://www.tb-training.co.uk/MarineE05.html

 

Tony

[cereal tiller]

my 230v fridge freezer is a 3/4 size "A"rated type

it uses around 75 amp hours over a 24hr period.

 

you could replace your diesel stove for a solid fuel one,and keep the rads and pump system.

[blackrose]

Before removing something like a diesel stove (especially a good one such as a Bubble), I would always recommend living with it over a winter or two just to see how you like it. However, I take the opposite view on the mains fridge. 75 a/h per day seems like a lot to me just to keep a bit of food cold. It's easy enough to remove that so I'd just get rid of it and get an efficient 12v model such as a Shoreline which should use a lot less power.

Edited May 30, 2011 by blackrose

[Robin2]

Before removing something like a diesel stove (especially a good one such as a Bubble), I would always recommend living with it over a winter or two just to see how you like it. However, I take the opposite view on the mains fridge. 75 a/h per day seems like a lot to me just to keep a bit of food cold. It's easy enough to remove that so I'd just get rid of it and get an efficient 12v model such as a Shoreline which should use a lot less power.

 

I have a "Coolzone" under-counter 230v fridge freezer which I bought from Comet. As far as I can see this is identical to the Shoreline RF88 except that Shoreline have converted it to 12v. Mine is an A rated appliance supposed to consume 220kWhr per annum. That's 50Ah per day at 12v - which is pretty close to what I'm experiencing. I presume the performance of the Shoreline version is similar unless they have added extra insulation - which I doubt. Of course I also need to run my inverter which consumes about 14 Ah over 24 hrs.

 

If you spend much of the time on shore power with cheap electricity I can't see it would make sense to change to a very expensive 12v fridge. However if you are generating all your own electricity the 12v version may make sense - the main saving will be the energy wasted by the inverter which consumes power even when the fridge is not running.

 

ETA

 

I'm stopped near Midland Chandlers right now and they have 15% off today which got me thinking whether it would make sense to change my own fridge as I generate my own power. However even if I saved all of the inverter "waste" it would only amount to about 60kWhr per year which I can generate for about £120. So it would take about 3.5 years to get my money back - too long.

Edited May 30, 2011 by Robin2

[bottle]

I run a full size 240v fridge and a full size 240v freezer via inverter from 340 amp hour bank at 24v.

 

I do turn them off at night, (22.00 to 08:00) when the inverter is also turned off.

 

The batteries are charged for three hours a day, for one hour at a time, from inverter/charger, the charger is 50 amp 24 volt.

 

The charging regime may seem odd but it coincides with our heavy usage, the electric oven and hob etc.

 

Batteries are always kept at above 50% SOC but rarely get to 100% SOC.

[Dibbo]

Looking at things, and comments, I think the fridge/freezer should be changed ASAPA (afforded) the diesel heater will be a wait and see.

[nb Innisfree]

cerial tillers 75 ah sounds like quite a big F/Freezer, usually a freezer uses about the same as a fridge so for a normal sized one it should use about 50-60 ah, not a great deal in the great scheme of things, should be ok provided you have enough batteries and a decent alternator/charger.

[Roger Gunkel]

I agree that cerial tiller's fridge/freezer consumption is unusually high at 75ah per day. I have a Hotpoint 6ft 50/50 fridge freezer that I did a power check on last year. I ran it via a power meter for 2 weeks and it averaged out at 46ah per day, which I was highly delighted with

 

Roger