Загрузка белья слишком большая.

Because it agrees with загрузка, which is a feminine singular noun.

• загрузка = feminine
• so the adjective must also be feminine singular:
  • большой → masculine
  • большая → feminine
  • большое → neuter

Even though бельё is neuter, большая is not describing бельё. It is describing загрузка.

Because загрузка often takes a dependent noun in the genitive: загрузка чего? = loading / load of what?

So:

• загрузка белья = load of laundry / loading of laundry

This is a very common Russian pattern:

• чашка чая = a cup of tea
• бутылка воды = a bottle of water
• загрузка белья = a load of laundry

So белья is the genitive singular form of бельё.

In Russian, the verb to be is usually omitted in the present tense.

So:

• Загрузка белья слишком большая. literally looks like
• Load of laundry too big.

But it means:

• The laundry load is too big.

This is completely normal Russian. In the past or future, a form of to be appears:

• Загрузка белья была слишком большая. = The load was too big.
• Загрузка белья будет слишком большая. = The load will be too big.

Because the adjective is attached to загрузка, not to бельё.

The structure is:

• [Загрузка белья] = the laundry load
• слишком большая = too big

So the main noun of the subject is загрузка, and that noun controls agreement.

A good way to see it:

• Загрузка = the load
• белья = of laundry

So the sentence is really:

• The load of laundry is too big.

Not:

• The laundry is too big.

Yes, it can be natural, especially in instructions, appliance messages, or more technical language.

It sounds like something you might see:

• in a washing machine manual
• on a display
• in a warning message

In everyday speech, people might also say things like:

• Слишком много белья. = There’s too much laundry.
• Загрузка слишком большая. = The load is too big.
• Ты слишком много белья положил(а). = You put in too much laundry.

So загрузка белья слишком большая is understandable and natural, but slightly more formal or technical than some everyday alternatives.

In this context, бельё means laundry.

This word can mean different things depending on context, such as:

• underwear
• bed linen
• laundry

Here, because of загрузка and the likely washing-machine context, it clearly means laundry.

So learners should remember that бельё is a context-dependent word.

Yes, absolutely. That is a very common alternative.

The difference is mainly in focus:

• Загрузка белья слишком большая.
  Focus: the load is too large.

• Слишком много белья.
  Focus: there is too much laundry.

Both can fit the same real-life situation. The first sounds a bit more specific to the idea of a machine load; the second is more general and conversational.

It is nominative feminine singular.

Why nominative? Because it is part of the predicate describing the subject:

• Загрузка белья = subject
• слишком большая = what is said about the subject

In simple present-tense sentences like this, Russian often uses the adjective in the nominative:

• Комната большая. = The room is big.
• Проблема серьёзная. = The problem is serious.
• Загрузка белья слишком большая. = The laundry load is too big.

Yes. Russian word order is flexible, although different orders can sound slightly different in emphasis.

Possible versions:

• Загрузка белья слишком большая.
  Neutral statement.

• Слишком большая загрузка белья.
  More like Too large a laundry load; sounds a bit more label-like or descriptive.

• Загрузка слишком большая.
  Natural if the context already makes it clear that we mean laundry.

Russian word order often changes emphasis rather than basic meaning.

Sometimes Russian uses short-form adjectives in predicates, but with большой, the full form is much more normal here.

So:

• Загрузка белья слишком большая. = natural
• Загрузка белья слишком велика. = also possible, a bit more formal/bookish
• Загрузка белья слишком больша. = not correct modern Russian

So for this sentence, большая is the standard choice.

A helpful stress guide is:

• загрУзка
• бельЯ
• слишкОм
• большАя

So roughly:

zag-RUZ-ka bel-YA slish-KOM bol-SHA-ya

The stress matters a lot in Russian, especially in words like белья and большая.

Very often, yes. Here слишком means too, in the sense of more than is acceptable or desirable.

So:

• слишком большая = too big
• слишком много = too much
• слишком быстро = too fast

It usually expresses excess, not just a high degree. So it is stronger than simply saying very.

Compare:

• очень большая = very big
• слишком большая = too big

Yes, very likely. Without more context, many learners would naturally understand it as something like:

• the washing machine load is too large
• you put in too much laundry

That is why загрузка белья makes sense here: it sounds like the kind of phrase used for machine capacity, instructions, or warnings.