W razie gdyby podkurzacz nie działał, nie otwieraj ula.

W razie gdyby is a more cautious, contingency-style way to say if.

• jeśli = plain if
• gdyby = if in a more hypothetical sense
• w razie = in case / in the event of

So W razie gdyby podkurzacz nie działał... means something like:

• In case the smoker doesn’t work
• If it should happen that the smoker doesn’t work

It sounds a bit more like an instruction, warning, or safety guideline than simple everyday jeśli.

After gdyby, Polish normally uses the -ł form of the verb, even when the meaning is not past.

So:

• działał by itself can mean he/it was working
• but gdyby działał means if it were working / if it should work

In other words, after gdyby, this past-looking form helps build a hypothetical condition. It does not mean the action happened in the past here.

Because the conditional marker by is already present inside gdyby.

So Polish says:

• gdyby działał = if it worked / if it were working

Not:

• gdyby działałby ❌

Using by twice here is ungrammatical. Once gdyby is there, the verb stays in the -ł form without another by.

This is about aspect.

• otwierać = imperfective
• otworzyć = perfective

In Polish, negative commands usually prefer the imperfective:

• nie rób = don’t do
• nie idź is actually from an imperfective/suppletive pair, but the general tendency remains
• nie otwieraj = don’t open

So nie otwieraj ula is the normal way to say don’t open the hive.

A positive one-time command would often use the perfective:

• otwórz ul = open the hive

But for prohibitions, Polish usually goes with the imperfective: nie otwieraj.

Because after a negated verb, Polish often uses the genitive instead of the accusative. This is called the genitive of negation.

Compare:

• affirmative: otwierać ul = to open the hive
• negative: nie otwierać ula = not to open the hive

So:

• ul = nominative/accusative singular
• ula = genitive singular

In this sentence, ula is the expected standard form after nie otwieraj.

Ula is genitive singular of ul.

The noun is:

• ul = beehive

Its singular forms include:

• nominative: ul
• genitive: ula
• accusative: ul

Because the verb is negated (nie otwieraj), Polish uses the genitive here, so you get ula.

Because it agrees with podkurzacz, which is a masculine singular noun.

In the gdyby + -ł structure, the verb form agrees in gender and number with the subject:

• podkurzacz → działał
• if the subject were feminine, you would get działała
• if it were neuter, działało
• if plural, działały or działali, depending on the group

So the masculine ending in działał tells you that podkurzacz is grammatically masculine.

W razie is a fixed expression meaning in case or in the event of.

You can use it with a noun:

• w razie pożaru = in case of fire
• w razie problemów = in case of problems

And you can also use it before a clause, as here:

• w razie gdyby... = in case it should happen that...

So in this sentence, w razie adds the idea of precaution: this is advice for a possible situation.

Because W razie gdyby podkurzacz nie działał is a subordinate clause, and the main command follows it:

• subordinate clause: W razie gdyby podkurzacz nie działał
• main clause: nie otwieraj ula

Polish separates these clauses with a comma.

Also, there is no comma between w razie and gdyby. They belong together here as part of one expression introducing the condition.

Yes. That is perfectly grammatical.

It would mean roughly:

• If the smoker didn’t work, don’t open the hive
• If the smoker should fail, don’t open the hive

Compared with w razie gdyby, plain gdyby is a little less explicitly about precaution. The original version sounds more like an instruction in a manual or safety guideline.

You could also say:

• Jeśli podkurzacz nie działa, nie otwieraj ula

That version is simpler and more straightforward, but slightly less formal and less contingency-focused than w razie gdyby.