Ta klimatyzacja jest za mocna, a ten wentylator zbyt głośny do spania.

Because Polish adjectives and demonstratives must agree with the noun’s gender, number, and case.

• klimatyzacja is a feminine noun, so you use ta = this
• wentylator is a masculine noun, so you use ten = this

So:

• ta klimatyzacja = this air conditioning
• ten wentylator = this fan

For the same reason: adjective agreement.

The adjective has to match the noun:

• klimatyzacja is feminine → mocna
• wentylator is masculine → głośny

Compare:

• mocny wentylator = a strong fan
• mocna klimatyzacja = strong air conditioning

And:

• głośny wentylator = a loud fan
• głośna klimatyzacja = loud air conditioning

Za before an adjective usually means too in the sense of excessively.

So:

• za mocna = too strong
• za głośny = too loud
• za zimno = too cold

In this sentence, Ta klimatyzacja jest za mocna means the air conditioning is stronger than is comfortable or appropriate.

Both za and zbyt can mean too, but they are used a little differently.

• za + adjective/adverb is very common in everyday speech

  • za mocna = too strong
  • za głośny = too loud

• zbyt + adjective/adverb also means too, but often sounds a bit more formal, careful, or stylistically neutral

  • zbyt głośny = too loud

So the sentence mixes them:

• za mocna
• zbyt głośny

That is grammatically fine. A speaker could also say:

• Ta klimatyzacja jest za mocna, a ten wentylator za głośny do spania.
• Ta klimatyzacja jest zbyt mocna, a ten wentylator zbyt głośny do spania.

All are natural.

It could, but Polish often omits repeated words when the meaning is clear.

Full version:

• Ta klimatyzacja jest za mocna, a ten wentylator jest zbyt głośny do spania.

More natural, less repetitive version:

• Ta klimatyzacja jest za mocna, a ten wentylator zbyt głośny do spania.

English does this too sometimes:

• The AC is too strong, and the fan too loud for sleeping.

So the omitted jest is understood.

Do + verbal noun often expresses for doing something.

• spanie = sleeping
• do spania = for sleeping / to sleep with

So:

• zbyt głośny do spania = too loud for sleeping

This structure is very common:

• dobre do jedzenia = good to eat
• łatwe do zrobienia = easy to do
• za zimno do pływania = too cold for swimming

After do, Polish normally uses a noun form, not the infinitive.

• spać = to sleep
• spanie = sleeping, sleep (as a verbal noun)
• do spania = for sleeping

So Polish says:

• do spania = for sleeping not
• do spać ❌

This is a very common pattern in Polish grammar.

It usually means the air conditioning in a general or practical sense. Depending on context, it could refer to:

• the AC system
• the air coming from it
• the setting/effect of the AC

In this sentence, Ta klimatyzacja jest za mocna most naturally means something like:

• This air conditioning is too strong
• The AC is too strong

English often uses the AC in the same broad way.

Yes, mocny basically means strong, but in Polish it is often used more broadly than English strong.

With klimatyzacja, mocna can mean:

• too powerful
• too intense
• blowing too hard
• cooling too aggressively

So za mocna klimatyzacja is a natural Polish way to say the AC feels too strong or intense.

No, do spania is the natural expression here.

• zbyt głośny do spania = too loud for sleeping

Using dla here would sound unnatural. In Polish, do is commonly used with this kind of purpose/suitability meaning:

• za twarde do siedzenia = too hard to sit on
• za ciemno do czytania = too dark for reading
• zbyt głośno do pracy = too noisy for working

Yes, Polish word order is flexible, though some versions sound more natural than others.

Original:

• Ta klimatyzacja jest za mocna, a ten wentylator zbyt głośny do spania.

Also possible:

• Ta klimatyzacja jest zbyt mocna, a ten wentylator za głośny do spania.
• Ten wentylator jest zbyt głośny do spania, a ta klimatyzacja za mocna.

The original order is natural and clear. Polish often keeps the most important descriptive part near the end of each clause.

A rough English-friendly pronunciation would be:

• Ta klimatyzacja jest za MOC-na, a ten wentylator zbyt GWO-shny do SPA-nya.

A few helpful sound notes:

• kl in klimatyzacja is like English kl
• ty in klimatyzacja is a normal Polish t
  • i/y-like vowel, not like English tie
• ł in głośny sounds like English w, so głośny starts roughly like gwo-
• ś is a soft sh sound
• spania ends roughly spa-nya

Possibly, but za mocna is more natural here.

Both mocny and silny can relate to strength, but they are not always interchangeable.

• mocny often fits things like coffee, wind, smell, air conditioning, effect, sound
• silny is often used more for physical strength, force, intensity, or strong effects in a slightly different sense

For AC, za mocna is the phrase a learner is more likely to hear.