Han sjekker luftstrømmen så vel som vibrasjonen.

In Norwegian, -en is a very common ending for the definite singular of many masculine and feminine/common-gender nouns.

So:

• luftstrøm = airflow
• luftstrømmen = the airflow

and

• vibrasjon = vibration
• vibrasjonen = the vibration

Unlike English, Norwegian usually adds definiteness to the end of the noun instead of using a separate word like the.

Because in Norwegian, the definite form is usually built into the noun itself.

Compare:

• en vibrasjon = a vibration

• vibrasjonen = the vibration

• en luftstrøm = an airflow
• luftstrømmen = the airflow

So the sentence does not need a separate word equivalent to English the here.

Så vel som means as well as.

In this sentence:

• Han sjekker luftstrømmen så vel som vibrasjonen.
• He checks the airflow as well as the vibration.

It links two things that are both included.

It is a bit more formal or polished than simply using og (and). It often suggests not only X, but also Y.

Yes, you often could.

For example:

• Han sjekker luftstrømmen og vibrasjonen.

This means He checks the airflow and the vibration.

The difference is mostly in style and nuance:

• og = plain and
• så vel som = as well as, slightly more formal, sometimes emphasizing that both are included

So both are possible, but så vel som gives a slightly different tone.

Yes. A very natural alternative is:

• Han sjekker både luftstrømmen og vibrasjonen.

This means He checks both the airflow and the vibration.

Compared with så vel som:

• både ... og strongly emphasizes both
• så vel som is a bit more formal and closer to as well as

All of these are grammatical, but they are not identical in tone.

Sjekker is the present tense of å sjekke (to check).

So:

• å sjekke = to check
• sjekker = checks / is checking

In Norwegian, the present tense is the same for all subjects:

• jeg sjekker = I check
• du sjekker = you check
• han sjekker = he checks
• vi sjekker = we check

Norwegian verbs do not change as much as English verbs do.

Because han is the person doing the action, so the verb should be in the active form:

• Han sjekker = He checks

A form like sjekkes is passive and would mean something like:

• Det sjekkes = It is being checked

So here, sjekker is correct because he is the one performing the checking.

Yes. Norwegian very often forms compound nouns by joining words together.

Here:

• luft = air
• strøm = stream / flow / current
• luftstrøm = airflow
• luftstrømmen = the airflow

This is very common in Norwegian, and English speakers often need some practice getting used to long compound words being written as one word.

Both orders could be possible depending on context, but the chosen order probably reflects what the speaker wants to mention first or emphasize slightly more.

This sentence presents two objects of sjekker:

1. luftstrømmen
2. vibrasjonen

Norwegian word order here is straightforward: verb first after the subject, then the things being checked.

So:

• Han = subject
• sjekker = verb
• luftstrømmen så vel som vibrasjonen = object phrase

There is nothing unusual about the order.

Normally, no comma is needed here.

So this is correct:

• Han sjekker luftstrømmen så vel som vibrasjonen.

A comma would usually not be used unless the sentence were structured differently for stylistic reasons. In a simple sentence like this, no comma is the normal choice.

In Bokmål, many nouns can behave as common gender, and the definite singular often ends in -en.

With vibrasjon, the usual definite form is:

• vibrasjonen

Even if a noun is conceptually feminine in some systems, Bokmål often allows or prefers the common-gender-style ending -en for many nouns, especially words like this one.

For learners, the important thing is simply to learn:

• en vibrasjon
• vibrasjonen

Yes, it is grammatical and natural.

That said, in everyday speech many speakers might more often say:

• Han sjekker luftstrømmen og vibrasjonen.
• Han sjekker både luftstrømmen og vibrasjonen.

The version with så vel som is still correct, but it can sound a little more formal or written.

Yes. Norwegian present tense often covers both ideas, and context tells you which one is meant.

So:

• Han sjekker luftstrømmen ...

can mean either:

• He checks the airflow ...
• He is checking the airflow ...

If the context is a general habit, English may use checks.
If the context is happening right now, English may use is checking. Norwegian often uses the same present-tense form for both.