Si el ventilador se avería, abrimos la ventana para sentir el aire fresco.

After si for a real or possible condition in the present/future, Spanish normally uses the present tense, not the future tense.

So:

• Si el ventilador se avería... = If the fan breaks down...

Not:

• Si el ventilador se averiará... ❌

A very common pattern is:

• Si + present, present
• Si + present, future
• Si + present, imperative

Examples:

• Si llueve, no salimos.
• Si llueve, nos quedaremos en casa.
• Si llueve, cierra la ventana.

In your sentence, abrimos is also present tense, giving a habitual or general meaning: If the fan breaks down, we open the window.

Here, averiarse is a very common pronominal verb meaning to break down, to stop working, or to develop a fault.

So:

• El ventilador se avería = The fan breaks down
• Se ha averiado = It has broken down

Without se, averiar is usually transitive:

• La tormenta averió el ventilador = The storm damaged the fan

So the difference is roughly:

• averiar algo = to damage/break something
• averiarse = to break down

The se does not mean himself/itself here in a literal reflexive sense. It is simply part of the verb averiarse.

Yes, abriremos is possible, but it changes the feel slightly.

• Si el ventilador se avería, abrimos la ventana.
  This sounds like a habitual action, a general rule, or something we normally do.

• Si el ventilador se avería, abriremos la ventana.
  This sounds more like a specific future plan: if that happens, then we will open the window.

Spanish often uses the present tense where English might use will, especially for routines, instructions, or general truths.

Yes, absolutely. Both word orders are natural:

• Si el ventilador se avería, abrimos la ventana
• Si se avería el ventilador, abrimos la ventana

The second version puts slightly more focus on the event se avería first. Spanish word order is often more flexible than English, especially when the meaning is still clear.

Because the subject of both actions is the same.

In the sentence:

• abrimos la ventana = we open the window
• para sentir el aire fresco = in order to feel the fresh air

The implied subject of sentir is the same we, so Spanish uses:

• para + infinitive

If the subject changes, Spanish usually uses:

• para que + subjunctive

Compare:

• Abrimos la ventana para sentir el aire fresco.
  = We open the window so that we can feel the fresh air.

• Abrimos la ventana para que entre aire fresco.
  = We open the window so that fresh air can come in.

Both can exist in Spanish, but el aire fresco sounds very natural here because it refers to a specific thing you experience: the fresh air.

• sentir el aire fresco = feel the fresh air

Using the article often makes Spanish sound more natural than a direct word-for-word translation from English.

Compare:

• Necesitamos aire fresco = We need fresh air
• Queremos sentir el aire fresco = We want to feel the fresh air

So the article is not random; it depends on how specific or concrete the noun feels in context.

They are similar, but not identical.

• aire fresco = cool/fresh air, usually pleasant
• aire frío = cold air, which can be neutral or unpleasant

In this sentence, aire fresco fits better because opening a window suggests you want a pleasant breeze or cooler air, not necessarily something cold.

So:

• sentir el aire fresco sounds natural and positive
• sentir el aire frío would suggest colder air specifically

Yes, notar is possible, but sentir is the more natural choice in this context.

• sentir el aire fresco = to feel the fresh air
• notar el aire fresco = to notice/feel the fresh air

Sentir often refers to physical sensation directly.
Notar can suggest becoming aware of something.

So:

• Abrimos la ventana para sentir el aire fresco = very natural
• Abrimos la ventana para notar el aire fresco = understandable, but less idiomatic here

Yes, it is standard to use a comma when the si clause comes first.

So:

• Si el ventilador se avería, abrimos la ventana.

If the main clause comes first, the comma is usually not used:

• Abrimos la ventana si el ventilador se avería.

This is similar to English punctuation with introductory clauses.

Spanish often uses definite articles more than English does.

So:

• abrimos la ventana = we open the window

Even when English might sometimes say open a window, Spanish often prefers the article when the object is understood from the situation.

Compare:

• Cierra la puerta
• Abre la ventana
• Apaga la luz

This is very normal Spanish usage.

Avería is pronounced roughly ah-beh-REE-ah.

The written accent shows that the stress falls on rí:

• a-ve-rí-a

Without the accent, Spanish stress rules would suggest a different pronunciation. The accent mark tells you the stressed syllable clearly.

Also note that í-a forms a hiatus here, so the vowels are pronounced separately:

• rí-a not as one merged sound.

Yes. By itself, abrimos can be either:

• present: we open
• preterite: we opened

The context tells you which one it is.

In this sentence, because of si el ventilador se avería, the meaning is clearly present/habitual:

• If the fan breaks down, we open the window

If it were past, the context would be different:

• Ayer abrimos la ventana. = Yesterday we opened the window.

Most naturally, it describes a general habit, routine, or standard response.

• Si el ventilador se avería, abrimos la ventana.
  = If the fan breaks down, we open the window.

It sounds like that is what we do in that situation.

If you wanted to make it sound more like one future situation, you might say:

• Si el ventilador se avería, abriremos la ventana.

So the present tense here gives a broader, more habitual meaning.