The thermos does not keep warm: why? Thermos does not keep warm Why does the second one cool down quickly in a thermos

A thermos is an indispensable device for any trip, allowing you to keep any liquid, be it tea, coffee or compote, hot and tasty. Despite the simplicity of its design and simplicity, it fails quite easily. Let's try to figure out what malfunctions exist, why they occur, and how to repair this device yourself at home.

Possible faults

Considering the simplicity of the design of the device in question, there may not be many possible malfunctions:

The thermos does not hold the temperature, that is, it cools down quickly;
it gets very hot outside;
broken button on the lid.

Some other problems may be caused solely by physical damage - chips, cracks, dents, that is, solely by physical factors.

Causes of problems

Now let’s try to understand in more detail the reasons for the problems described above.

If a stainless steel thermos stops holding heat, this usually happens after using the device for some time. The causes of poor thermal insulation can be:

damage to the plug;
poor quality or deformed silver plating;
there is no vacuum layer between the walls of the body and the cylinder.

If we talk about the first problem, it often happens that the plug was already defective from the very beginning. But it could also happen that the owner of the thermos screwed it too tightly, and after a while the connection simply cracked, and therefore the device stopped holding heat. It’s easy to check – just tilt a closed metal thermos. If there is such a defect, hot water will leak out.

If the thermos has a glass flask, then inside it there is a damaged or poor-quality silver coating. Usually we are talking about a manufacturing defect.

The problem may also be the lack of vacuum between the body and the walls of the cylinder. Almost any thermos that exists today, even any Chinese one, has a double bottom. A copper tube passes through it inside, the end of which is flattened. It is through this tube that the manufacturer pumps out air using a special vacuum pump.

It also happens that the thermos gets hot. This is bad, because then the phenomenon of thermal conductivity appears. The hot liquid inside transfers heat to the body, which releases it into space.

Manufacturers often use inert gas as insulation. It is especially often used in Chinese models, instead of creating a vacuum layer. It's easy to fix - just take it to a workshop, where the technician must use a special pump to restore the vacuum or add gas. If the problem is a cracked bulb, it should be replaced.

To prevent problems from occurring, the thermos, despite its simplicity, requires careful handling and careful operation.

How to disassemble a thermos?

But if you decide to do the repairs yourself at home, you should first disassemble the device being described. Most often on the market there are models with a lid in which the button is located. There are several instructions for disassembling such devices. The first one will be the simplest:

You should carefully unscrew the clamping ring counterclockwise so as not to break this plastic element;
remove the valve from the thermos;
we take out the valve mechanism for further disassembly;
now it turns out to be divided into 3 parts - we find a spring, a button and other auxiliary parts;
we disassemble the button itself by pushing out the valve stem so as not to damage the retaining ring;
We wash all the parts and check their integrity.

Now the button should be assembled in reverse order.

The second instruction will differ in that the lid is complicated by the presence of a second button:

the lid is pryed off with a thin metal blade or any other similar object;
the device has hidden latches that should be carefully bent so as not to break them;
after this, a view of all the details that are inside opens up.

Assembling such a cover will be carried out in the reverse order.

Let's move on to disassembling the thermos itself. First, let’s make sure that the thermos flask is intact; to do this, you need to take it out.

To carefully disassemble an iron thermos, you should take a sharp knife, insert it into a special seam and very carefully, by tapping with a hammer, separate the inner part from the body. This will complete the disassembly process.

How to repair?

If we talk about repairing a thermos, we wrote above what to do in case of a broken lid or damaged coating. Let's consider what to do if there is less vacuum in it, but you don’t want to take it to the service center. You can create a vacuum layer yourself.

If you have taken out a glass flask and made sure that its integrity is not compromised, then it should be insulated using isolon, and then wrapped with tape or strong twine. Now we place it back into the case, having previously replaced the special insulating rubber band. It should be said that This thermos will not keep warm for a long time, as before, but it will last for several hours.

If the flask inside the thermos is made of metal and there is no damage to it, then the problem may be in the rubber bands that act as a seal. They can be easily replaced by taking them from another device, buying them at a hardware store, or making them yourself from a piece of rubber.

If cracks are nevertheless found in the metal flask, then the space between the flask and the body can be filled with granular foam or polyurethane foam. You can also fill the space with Christmas tree tinsel. But in this case, all these methods will only be a temporary solution. In case of such damage, it would be wise to purchase a new thermos, since a repaired one will not last long.

If repairs are necessary if the housing is damaged on the outside, you can contact a car workshop, where they can repair it using liquefied gas. True, the cost of such repairs will be too high, which makes this procedure simply impractical.

Another option, if the appearance is not particularly important, then you can take out the flask and carefully tap the body from the inside with a hammer. It is not necessary to create a perfect appearance; you just need to make sure that the walls of the flask do not touch the body from the inside.

Repair will not be possible if the glass bulb has cracks or chips. Deformations of this type pose a threat to human safety. Therefore, it is better to simply throw away a thermos with such damage.

If you are faced with a lack of vacuum in a thermos, then to correct this problem you will need to do the following: make a hole inside the thermos, insert a tube into it and solder it. It will be needed to pump out air. Now you need to start pumping the container with air to see if the container is leaking air somewhere. We put the thermos in a bucket of water and gradually begin to apply pressure to it. A pressure of 2 kilograms will be enough to prevent the container itself from inflating.

When the defect is discovered, you should take a soldering iron and seal the place where the container is leaking. Now you need to pump out the air. To do this, we make a clamp and start the electric pump.

When the pressure is at the level of 1 kilogram, the tube should be pressed. Now we seal its tip to block the access of air. In addition to the vacuum, there must also be a mirror coating so that it reflects infrared rays from the walls. This will keep the thermos warm even longer. This will complete the repair.

Operating rules

Now we should say a little about how to use a thermos correctly. It seems that everything is simple, but many people, for some reason, manage to use even such a simple device incorrectly.

Before purchasing, you should inspect the product as carefully as possible for physical external damage. You need to see how tightly the lid fits, and whether the thermos makes any extraneous sounds. You can also sniff it to check for any unpleasant odors. If they are, then it is very possible that it is made from not the highest quality materials.

If the materials from which the thermos is made look suspicious, then it is better to refuse to purchase such a product. If you are often on the road, it is better to purchase a large-capacity thermos. This will not only allow you to take more warm drinks with you. Such models retain heat much better than their smaller counterparts.

If you purchased a model similar to a siphon, you should know that it has a significant drawback. It lies in the fact that heat is retained worse here due to certain features of the cork, due to which it is not completely sealed.

It is preferable to buy thermoses made of stainless steel. They retain heat better than plastic solutions. The flask will also be important. It would be good if the flask was made of thermal glass. This will allow the liquid to cool more slowly due to the silver coating.

It should also be noted that metal thermoses that have a glass flask should not be immediately tested by pouring boiling water. It is better to first pour a little hot water to warm the walls. The fact is that glass really does not like serious temperature changes.

In this article we want to analyze the reasons for the poor heat capacity of thermoses, as well as solutions that will allow you to avoid mistakes when purchasing thermoses and thermal mugs .

First, let's understand the structure of a thermos.

Of course, there are a huge number of companies that produce thermoses and thermal mugs. But, as a rule, any thermos consists of identical parts: an outer and inner flask, a vacuum layer between the flasks, a lid and a valve.

Outer flask

The outer flask of a thermos can have a wide variety of looks, but its purpose is one and very simple - to make the thermos look cool and delight you with its design every day :) The outer flask can consist of stainless steel, acrylic, plastic and even ceramics - depending on the company and the model of your thermos. The outer flask can have handles, carabiners, silicone potholders, etc.

Inner flask

The most important part of any thermos. Its purpose is to take on the entire temperature of the drink inside and keep it hot for the stated time. The high-quality inner flask of the best thermoses is made of stainless steel. It holds temperature excellently, does not change the taste of drinks and does not emit toxic substances even at high temperatures.

Vacuum layer

The distance between the outer and inner flasks is filled with vacuum - it does not conduct heat and that is why the thermos perfectly maintains the original temperature of drinks. Of course, some thermoses use not only double-wall technology with a vacuum between them, but also special mirror materials. However, according to statistics, such thermoses are less durable and break more often. Our thermoses have a vacuum layer and retain heat perfectly due to high-tech equipment. STARBUCKS™ thermoses do not contain mirror materials, which over time can crack inside and give an unpleasant “salt shaker” effect (noise inside from fragments).

Thermos lid

The only place where there is no layer of vacuum between the walls is the lid of the thermos. The lid can be made of different materials, but the most appropriate is organic plastic. It won't burn your lips like stainless steel would, and it won't break or crack after a week of use like ceramic lids.

Valve

Not all thermoses have a valve: a special “organ” that is located in the lid and makes drinking drinks easier. However, without a valve, using a thermos turns into a real nightmare: the thermos must be constantly unscrewed/tightened. It is much more convenient to use a thermos with a valve - just open the lid slightly and aromatic coffee will already tickle your nose :)

Why doesn't the thermos keep the temperature?

There are several reasons why a thermos does not keep the temperature. Whether it is cold or warm, the reasons for the poor heat capacity of a thermos are always the same. Below we have collected the top reasons why a thermos may disappoint you after purchase.

Defects in production

The most common reason for poor heat capacity of a thermos is a banal manufacturing defect. A cracked flask inside or lack of vacuum between the walls. Of course, the dry statistics of factories “1 defect in 1000 models is normal” does not interest the buyer, and we understand this like no one else: the buyer bought one thermos, not a thousand. And for him, all 100% of thermoses (that is, one) are defective. So we left the statistics for the accounting department, and we ourselves began to carefully check the goods at production, upon arrival in Moscow and before delivery to the client. It takes a little time, but all clients are happy :)

Retailer's carelessness

Another common reason why a thermos does not keep warm or cold is poor quality control in the store. A broken lid or ignorance of the product - the blame for such ignorance lies on the shoulders of the retailer. No one can say for sure whether this is intentional or not, and, often, this point originates from the previous one: after all, if there were no defects in production, there would be no defects in the store...

Incorrect operation

Equally rare are cases where thermoses are put in the microwave, pure alcohol is poured into them, washed in the dishwasher and handled carelessly. Any use of a thermos for other than its intended purpose causes damage to the internal flask and lid, which can cause poor heat capacity of your thermos, and, at the same time, is unlikely to be a warranty case (if it turns out that you, for example, tested your V-Shaped White for strength with armor-piercing bullets ).

Defective goods

Here, as they say, there is no need to say anything. In the era of the Internet, the network is replete with one-pagers, resellers of fakes from Aliexpress, as well as simply scammers who are ready to snatch their money as quickly as possible, leaving you without money and without quality goods. Always ask for a guarantee - this will save you from negative emotions and give you real pleasure from buying a thermos.

But what should I do if my thermos doesn’t hold the temperature at all?

If you bought a thermos or thermal mug from us, we assure you that nothing bad happened :) Just write or call us and we will do it for freeWe will exchange the thermos for a new one or replace the lid if you have cracked or lost it.

If you boughtthermoses and thermal mugs not in our store, you can write to support, hang around for hours waiting for an operator, and then ask for a refund...

Or you can just call StarbucksShop and we will replace your thermos with a completely new one with a 12% discount! Just like a trade-in at a car dealership - we'll exchange the old oneleaking thermosfor a completely new branded one, and even with a 12% discount :)

By the way, if we are talking about our thermoses, then there is nothing to be afraid of - we give a lifetime guarantee for each model and openly declare that if the thermos begins to leak or does not hold the temperature well, we will exchange it for free for a completely new one.

Conclusion

How to buy a thermos that will keep the temperature well

Choose well thermos store, where you are going to buy your travel companion, and also don’t be lazy to come to showroom and see the selected model in your hands.

Choose stores with real reviews, as well as stores that issue checks and provide you guarantees as a buyer. We also advise you to pay attention to the store’s presence on social networks and the number of subscribers in the group. It really makes a difference :)

Opt for a slightly more expensive stainless steel model rather than a cheaper plastic model. Miser pays twice...

Chat with a consultant and tell us what you prefer to drink - coffee or tea, whether you like hot, hot coffee or slightly warm: all this matters when buying a quality thermos.

Good luck with the right purchases;)
By the way, according to

Good afternoon, dear readers of my blog! I’m glad to share interesting information again, and today we’ll try to figure out together why the thermos doesn’t keep warm and what to do about it.

Several of my friends complained that they were disappointed with thermal cookware from well-known companies - they say that they have been using it for several months, and the heat hardly lasts anymore. Assuming that such a problem could await me in the future, I decided to take preventative measures. It turned out that the problem can be corrected, but it is better to prevent it. However, first things first.

What could have happened

There was little information on the Internet - only complaints and assumptions. But there are practically no proposals to solve the problem. Then I started interviewing friends who had such dishes. Everyone noted that at first the thermos did an excellent job of its direct responsibilities and only after a while it stopped retaining heat. At first I relied on my assumptions, which were partially justified.

In my opinion, the reasons for poor thermal insulation can be:

From everything I saw, I concluded: a thermos, even a completely metal one, is a thing that requires delicate use. Falls, impacts, and shocks can lead not only to damage to the glass flask, but also to the disappearance of vacuum and cracks in the valve plug.

How to solve a problem

Usually in such cases there is no question of what to do - of course, buy a new thermos. That's what I thought until recently.

But some of my friends approached the problem creatively and this is what they came up with.

One stubborn acquaintance of mine did a radical thing, permanently - as he suggests - solving the problem with the vacuum. He simply filled the space between the walls of the inner and outer cylinders with polyurethane foam. Time will tell how right he was about the durability of the thermos after such repairs. But I found this method interesting. I'll have to try it on inexpensive dishes. In any case, now my friend's thermos is not so prone to falling.

In the meantime, I haven’t experimented, but tried to find out in advance which thermos holds heat better - so as not to get into trouble when giving advice or buying similar dishes as a gift.

Varieties and brands

To fully answer the question of how long food and drinks should remain hot in a thermal vessel, you need to take into account several nuances.

Flask material. It is traditionally believed that thermal glass retains heat longer. This is 50% correct, since glass has less heat transfer + the silver coating plays a role.
The remaining 50% of the effectiveness of a thermos is based on vacuum. And if the model is made of stainless steel, then everything is 100%. So first of all you need to make sure that the vessel is completely sealed and the vacuum is not broken.
The size of the vessel also plays an important role - the larger the volume, the slower the heat will leave it. But this point is relevant provided that the thermos is filled to the top.
Models in the form of a siphon - with a pump - keep drinks hot for no longer than 6 hours. This is obvious, because their cork is not 100% sealed.

Having summed up all the facts, I came to the conclusion that thermoses from well-known brands hold the temperature best, and it doesn’t matter whether their flasks are glass or metal. The main thing is a high-quality vacuum. Firstly, a popular manufacturer will not risk its reputation and make a low-quality product. Secondly, when purchasing branded thermal cookware, you can always be sure that a defective model will be exchanged for you at any time, since some manufacturers provide a guarantee for their products for up to 100 years. For example, Stanley(USA). But this is only possible if you buy the product directly from official representatives of the company or the manufacturer itself.

I monitored the Russian market in search of the best brand and today it is:

"Amet" and " Biostal", made in Russia. These companies have been familiar to domestic manufacturers for decades. We can say that this is affordable, time-tested quality. The advantage of Russian brands is that they are not counterfeited, and you can always find the full address of the company on the box.
A famous brand for 110 years Thermos. The brand's concerns are located in England, Canada and the USA. But at the moment the manufacturer has moved its factories to China. Do not be afraid of the inscription “Made in China”, the main thing is that the manufacturer’s coordinates are indicated.
The German brand is completely trustworthy LaPLAYA– today in Russia they are produced by only one official distributor company, “Cold Technologies 2000”.

Thermoses, which of the listed companies retain heat best is difficult to say, but customer reviews are only positive.

Never buy a thermos at the market, from hand, or in subway passages - no one is responsible for the quality of the goods in such places. Let's educate ourselves together, see you soon!

If you want to stay informed, I'm in instagram, where I post new articles that appear on the site.

Thank you for your attention! Sincerely, Rostislav Kuzmin.

Your trusty travel assistant – the thermos – has recently started acting up. Coffee or tea cools down very quickly in it, in less than two hours. But before, the vessel has never let you down, stably holding heat all day long and even more. Remember, maybe it fell, or you were careless to put it on the table too abruptly? If your container has a flask made of glass, then such a rash movement will be quite enough to damage the product. Let's figure out why the thermos still doesn't keep warm?

Reasons for reducing the thermal insulation properties of the product:

Very often, the breakdown of a glass flask is caused by temperature fluctuations. This is when you immediately bring a thermos from a cold street and pour boiling water into it. Of course, such actions can burst any glass container, not to mention the delicate flask of a thermos.

What to do?

The further fate of the vessel is determined by the complexity of the breakdown. If the valve cover fails, try to repair it yourself using the instructions. You can buy this element from a thermos manufacturer and replace it. If the problem is in the vacuum, then you can contact the service center. The technician will pump out excess air, and the product will regain its heat-saving properties. If the flask is damaged, you will have to buy a new thermos.

Reliable thermos

You are lucky if your assistant is a STANLEY thermos. Products of this brand have a durable steel structure and reliable additional elements. If any of them fails, then you can send the vessel to the manufacturer for free repair. It is worth remembering that the warranty on Stanley thermoses lasts no less, but a hundred years! The technicians at the manufacturer’s service center will replace failed parts and repair all elements that need to be repaired. And in extreme cases, they will simply send you a new thermos.

5% Especially for readers of our blog, a 5% discount on the entire range of the store using the promotional code BLOG

STANLEY products are not subject to corrosion, have a double vacuum thermal insulation layer, and a sealed lid. Beverage containers will keep contents hot for up to 32 hours. If you have a STANLEY food thermos at your disposal, then you can count on a hot lunch even after 15:00. But be careful when buying this branded item, because there are many fakes on the market today.

This is not surprising, since any popular brand sooner or later begins to be counterfeited. If you are not sure of the quality of the product being offered, then ask the seller for a quality certificate. All original Stanley products have a special warranty card that confirms a hundred-year warranty. Buy such products only on official websites and from legal representatives of the company to protect yourself from counterfeit products.