Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Fridge/Freezer catches fire...why?

Status
Not open for further replies.
During the time that appliance was made the most common causes were relays short circuiting and interior bulb not turning off.
 

Tragedies can be triggered due to any events that have been flawed in the aspect of safety management and/or predictability. I'm not sure which path this thread will move on. Subjects such as these much often jump out the technical field and get into the administrative and even political arena, and the history of mankind shows an uncomfortable recurrence despite the lessons learned previously.

If you dont know the particular details, then please tell of any "fire-starter" electric circuits out there in consumer goods?

Hard to imagine in a heterogeneous environment like a residential building; it would be easier to want to know, not what would start the fire, but rather what would propagate the fire (or would not prevent it).
 

    V

    Points: 2
    Helpful Answer Positive Rating
Many products have underpowered and undercooled
motors (engineered by accountants) and depend on a
safety mechanism to keep from burning them out. A
refrigerator's start cycle has such an overcurrent
interrupter, on every one I've encountered. If that
fails closed, then start winding may burn if you try to
restart the compressor into a pressure head (like, you
open the door right after the compressor has cycled
off).

Have seen many reports of other compressor-
refrigeration products (like dehumidifiers) catching
fire.

Certification is done on virgin products, not ones with
random failed safety components.
 

In the the 80s we would install timers on AC condensers to prevent the compressor from trying to start against high head pressure. If the power blinked it would not allow the contractor to pull in till the pressures equalized. In today's programmable thermostats some have these off timer features built in. This doesn't prevent what dick freebird is talking about but definitely a worth while feature.
 

Hi,

Maybe a leakage in the refrigerator filled with highly flammable/exlosive refrigerant, combined with the spark in the relay...

I remember many years ago a house about 6 km away exploded. A leakage in the gas pipe (not related to the refrigerator) plus the spark of the refrigerator relay made a complete floor of the house to be blown away. It sounded like a huge supersonic bang of a plane.

Klaus
 

If you dont know the particular details, then please tell of any "fire-starter" electric circuits out there in consumer goods?

Looking objectively, a short circuit CANNOT start a fire unless there is something to pick it up locally. Nothing in the circuit is combustible (not even the working fluid) and the circuit always fails in the open circuit mode. The fuse or the circuit breaker might or might not have failed but that is far less important. The failed fridge/Freezer might have ignited some paper or clothes and INITIATED the fire.

Here in India I see most Fridge/Freezers use polystyrene foam as insulation; that is real DANGEROUS. That can set the fridge on fire. And even if you spot that within 30 seconds, it is tough to control. What kind of insulations are common over there?

Even if the insulation is enclosed (not openly visible) by other plastics, it is clearly not sufficient.

In India a large number of fires in buildings are caused by electrical short circuits- but that is only doing the simple job of lighting a match. Perhaps for every ten thousand short circuits, one building gets gutted. Most common points of short circuits are switches, relays, junction boxes, fuses and other connection points. Short circuit does not take place in the middle of the conduit. I had some problem with my air conditioner and I had to pull out the cable and discovered that the insulation has melted much over the area (but no fire and the fuses were getting blown: that was the early symptom).

In congested areas (in all big cities in India) the fridge is a designer piece and is used as a furniture and if the insulation catches fire, there is no going back. You should not waste time trying to put out the fire.

Of course I do not know the particular details but almost all electrical circuits kept in close proximity with books, clothes and similar stuff deserves greater respect. And actual circuit details or CE markings does not really matter when the device fails.
 

The process of refrigeration is not itself dangerous or a fire hazard. With the greatest respect to the victims at Grenfell Tower, and I was there a few days after the fire, there have been only 3 UK fires reported in the past year that were confirmed to come from faulty fridges. Given that 64,000 of that model alone were manufactured it puts the risk in perspective.

While not impossible that it was the cause of the fire, the most likely scenario is that it was incorrectly installed (maybe with inadequate ventilation) or was made incapable of cooling because of dust accumulation on the fans or compressor. Reports that that model was prone to blowing fuses randomly suggest it was over-protected rather than a danger.

My own 15 year old LG upright fridge/freezer needed attention last week. My good lady couldn't pull the bottom drawer out of the freezer because it was sitting in a pool of ice that locked it to the base. It was a simple fix, these 'frost free' systems work by periodically heating the cooling fins to melt accumulated ice then drain it to an evaporation chamber where is releases to the atmosphere, the drain hole was blocked by fur from the cat! Now, like most people, I don't keep the cat in the freezer so it shows how easy it is for drifting dust/fur/cobwebs to be blown by the fans to places it can cause a blockage. I'm not saying this was the cause of the Grenfell fire but the layers of dust that build up over the years can certainly cause problems and maybe overheating. There is nothing a manufacturer can do about that in a product that relies on the flow of room air to extract heat. Perhaps instructions to clean the air passages and fins could be put in instruction books but I fear that could cause far more problems when left to inexperienced consumers to tackle maintenance.

Brian.
 

A dangerous part of the refrigerant when it is exposed to a open flame is the phosgene gas that is produced. It adds to the already deadly cocktail of gases produced by the other products that are burning. Phosgene gas was used as a weapon during WWI and caused many injuries and deaths.
 

Tragically, the following fire caused multiple deaths…
https://en.wikipedia.org/wiki/Grenfell_Tower_fire

…it was started by a Hotpoint FF175BP Fridge/Freezer.....
https://www.hotpointservice.co.uk/fridgefreezer
What was the actual electrical circuit details, and howcome the product gained CE marking?

If you dont know the particular details, then please tell of any "fire-starter" electric circuits out there in consumer goods?

Why do we put fuses in our circuits?
 

Now, like most people, I don't keep the cat in the freezer.........

Brian.
:-D:-D

But now seriously; the short circuit is only the proverbial match in the gunpowder room. The short circuit may have happened, but what caused the fire to catch on and propagate? were there any local smoke alarms to provide an early warning?

In the area where I live, the building codes were updated 4 or 5 years ago to include smoke detectors on every room (except the bathrooms), in contrast to the previous code where only the kitchen required it.
Is this a cure-all? Well, only if you maintain the smoke detectors properly.

In the end, there is only so much that a designer can do to avoid people's stupidity and resourcefulness to jump the safety features.
 

i must admit i dont understand how the fire got from the fridge to the cladding on the outside of the building...specially when the kitchen did not have a window to the outside.
Also, the man whose flat it was had packed his bags and had them ready outside the flat when he then alerted his neighbours, ...and at that time , his neighbours described the fire as being "a small fire in the kitchen"......i guess there was no attempt made to put the fire out, and strangely, the windows must have been left open.
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top