Today we had a generator instead of the grid serving us

Yes I could, but since as yet power cuts have been minutes not really worth the effort, my wife has gone OTT with food, much in fridge or freezer, and it has been a worry although as yet is seems unfounded that we could loose it all in a power cut.
 
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A full freezer will stay safely frozen for much longer than you might expect - possible up to 48 hours if you don't open it:
https://www.food.gov.uk/safety-hygiene/food-safety-in-a-power-cut-advice-for-consumers
Indeed so, as I keep telling people. For a start, the temp of an unopened freezer, particularly a chest freezer, will stay low for a pretty long time. Perhaps more to the point, from the 'food safety' point of view (bacterial growth), in nearly all cases any temp appreciably below zero is adequate. The main reason for the low freezer temps we use is to prevent (chemical and physical) deterioration which may make some foods unpleasant to taste or appearance (but still usually 'safe').

As a result, I suspect that, despite some people's fears, hardly any power cuts of 'credible duration' are actually likely to result in significant 'loss of food'. The main risk of that happens arises when a freezer stops working, due to freezer failure or 'tripping' of its electricity supply whilst one is on holiday!

Kind Regards, John
 
Yes I could, but since as yet power cuts have been minutes not really worth the effort,...
Essentially the same here. We get lots of power cuts, I presume due to the operation of 'devices' in the distribution neywork (particularly when there is lightning around), but usually only for durations ranging from a small number of seconds up to a few minutes.

In the 35+ years that I ('pessimistically') have had a genny here, it has probably been used 'in anger' on 3 or 4 occasions, if that.
my wife has gone OTT with food, much in fridge or freezer, and it has been a worry although as yet is seems unfounded that we could loose it all in a power cut.
See what I 've just written about this. I think people probably get too concerned about this perceived 'risk'.

Kind Regards, John
 
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I had an upright freezer go bang while standing next to it. And I had a spare fridge/freezer in garage used for brewing. So went to garage and turned it on to freeze and waited ½ hour before starting to transfer food to allow it to cool. I think it was likely just at the end of a defrost cycle, but food in the top 9" of the freezer had already defrosted, stuff lower down still frozen solid.

So with a chest freezer yes likely 12 hours is not a problem, as they have no defrost cycles with domestic types, but an upright the time all depends when the last defrost cycle took place.

We tended to keep lolly ices in top of freezer, and even if defrosted for a very short time, they were then no good. All depends what the food is.
 
I had an upright freezer go bang while standing next to it. And I had a spare fridge/freezer in garage used for brewing. So went to garage and turned it on to freeze and waited ½ hour before starting to transfer food to allow it to cool. I think it was likely just at the end of a defrost cycle, but food in the top 9" of the freezer had already defrosted, stuff lower down still frozen solid.
Yes, 'defrost cycles' are a problem. They may in some senses be 'convenient', but inevitably result in temp in some parts of the freezer repaetedly rising to some extent. For that reason, if I could avoid it, I would never have a 'self-defrosting freezeer.
So with a chest freezer yes likely 12 hours is not a problem, as they have no defrost cycles with domestic types ...
That is very pessimistic. A reasonably full chest freezer which is not opened will be fine for a lot more than 12 hours without power. If it is opened, or if it does not contain much, then things become different.
, but an upright the time all depends when the last defrost cycle took place.
See above. I personally avoid them. I do have upright freezers, but not ones which 'auto-defrost'
We tended to keep lolly ices in top of freezer, ...
That is a little daft (even if convenient), since they are the one type of thing stored in freezers that are ruined by modest rises in temp! (amee problem with ice cubes :) )

Kind Regards, John
 
Yes, 'defrost cycles' are a problem. They may in some senses be 'convenient', but inevitably result in temp in some parts of the freezer repaetedly rising to some extent. For that reason, if I could avoid it, I would never have a 'self-defrosting freezeer.
If the freezer is working, then the fan moves the air around the freezer so there are no cooler or warmer spots with auto defrost as the fan is required as the cool bit is behind a divider, so it needs the fan. It also allows shelves to be removed for things like the Christmas turkey, so while working as designed they are a lot better than upright without auto defrost. They also tend to have features like showing the max temperature reached during a power cut, opening the door resets it. And inverter drive motors so less noise and smaller start up spikes.

However more expensive, and if one is unlucky enough for it to fail just after a defrost clearly a problem. But the one I talked about being used for brewing, had run for 20 years before being reused for important work. It was condemned due to insulation failure, thermal not electrical, but keeping brew to 19ºC this was not a problem. It was only scrapped because I was moving house, after 25 years, cheap non auto defrost don't tend to last that long.

Better cross fingers, I know 10 years guarantee, but finding the receipt now may be a problem, they must be getting near 10 years old. But the chest freezer was a stop gap, late mothers fridge/freezer was small so in a wheel chair she could reach the fridge, so when we moved in to look after her, the freezer was far too small, so got the chest freezer for the garage, both still working, the fridge/freezer only usually used for BBQ's but when daughter moved into out flat, she started to use it.

If one fails unlikely to be replaced, but if there is room, my wife fills it. And not only freezers.
 
Might be simplest to just add extra insulation to the garage freezer if in an area prone to power cuts..
 
My approach is similar, we have a small UPS that supports the systems the other half would hate losing - the internet - for a few hours, we have battery lamps and, because I don‘t expect long power cuts, we just wouldn’t open the freezer.

The fridge will stay cold for a few hours, if longer the chest freezer will get covered in duvets. Had a friend who lost power for 4 days one winter, when the power came back on his chest freezer content was still frozen solid.
 
If the freezer is working, then the fan moves the air around the freezer so there are no cooler or warmer spots with auto defrost as the fan is required as the cool bit is behind a divider, so it needs the fan.
Yes, I understand that.
It also allows shelves to be removed for things like the Christmas turkey,...
Yes, that is an advantage over standard upright freezers where the shelves are intimately connected to 'cooling pipes'.
so while working as designed they are a lot better than upright without auto defrost.
That's a matter of balancing pros and cons, about which opinions will undoubtedly vary.
They also tend to have features like showing the max temperature reached during a power cut,...
For reasons I've explained, that feature would not particularly interest me - and, in any event, there's surely no reason why a freezer without such a feature couldn't have such a feature?
And inverter drive motors so less noise and smaller start up spikes.
Again, that presumable is true whether or not it has auto-defrost?
.... if one is unlucky enough for it to fail just after a defrost clearly a problem.
That is one of the issues which concerns me a little, and hence one of the reasons I've avoided auto-defrost.
... If one fails unlikely to be replaced, but if there is room, my wife fills it. And not only freezers.
As I've implied, in some senses she is doing you a favour. As I've said, in the event of a loss of power, a freezer (of any type) will remain cooler for longer if it is crammed full of things than if there's only a little in it ;)

Kind Regards, John
 
It also allows shelves to be removed for things like the Christmas turkey, so while working as designed they are a lot better than upright without auto defrost. They also tend to have features like showing the max temperature reached during a power cut, opening the door resets it. And inverter drive motors so less noise and smaller start up spikes.

Good point, I will have to check on that though, in the new freezer..
 
Good point, I will have to check on that though, in the new freezer..
As I wrote to eric, I don't see why the 'max temp experienced' display or the inverter motor are, at least in theory, necessarily restricted to auto-defrost ones - so it's certainly worth looking/checking if those 'features' interest you.

The issue with the shelves is probably insuperable. With standard (not auto-defrost) upright freezers, the cooling pipes are essentially part of the shelves, which means that the shelves cannot be moved. With auto-defrost ones, the cooling pipes are external to the freezer's cavity, so that issue doesn't arise, so the shelves can be (and usually are) moveable.

Kind Regards, John
 
As I wrote to eric, I don't see why the 'max temp experienced' display or the inverter motor are, at least in theory, necessarily restricted to auto-defrost ones - so it's certainly worth looking/checking if those 'features' interest you.

I don't need to - the very handy gadget I bought some years ago, records the max, min, displays the current temperature, and alarms at a preset high, or low temperature. I only bought it, to warn when the door has been left open, as I once did.
 
Essentially the same here. We get lots of power cuts, I presume due to the operation of 'devices' in the distribution neywork (particularly when there is lightning around), but usually only for durations ranging from a small number of seconds up to a few minutes..

On the MV & upward network exist numerical protection relays. These are too expensive to justify use on anything below about 33kV. A protection relay can be considered, in simple terms, as a sophisticated programmable "fuse". As well as clever over current protection they can often be configured to do other ancillary functions such as "auto-reclose".

Auto-reclose is the ability to re-connect the line, after a short delay & 'see-what-happens'. If the fault is transient, like a tree branch touching the line, the line may stay closed & the event is over and done with. The protection engineer might even choose to apply a different, higher level of over-current setting for a few seconds in an attempt to "burn the fault clear". The relay may try this process several times before either succeeding or tripping out for a final time before locking out.

This 'auto-reclose' process is the explanation for the short interruptions that you see or why the power come sback on several times before finally going off & staying off.
 
.... Auto-reclose is the ability to re-connect the line, after a short delay & 'see-what-happens'. If the fault is transient, like a tree branch touching the line, the line may stay closed & the event is over and done with..... This 'auto-reclose' process is the explanation for the short interruptions that you see or why the power come sback on several times before finally going off & staying off.
That's the sort of thing I imagined when I referred to "devices in the distribution network", and it would seem that, at least around here the 'transient fault' is very often not a true 'fault' at all, but just the consequence of a flash of lightning.

As well as episodes of "the power come sback on several times before finally going off & staying off", we also quite often have episode s when "... the power comes back on several times before finally coming on and staying on".

Kind Regards, John
 

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