I recommend calling a specialist once or twice a year.

He will disassemble the combustion chamber, clean it, perform maintenance on the burner, and check the pressure in the expansion tank and the boiler settings.

As a rule, formal maintenance is carried out by employees of the gas supply organization. They inspect the boiler and draw up a report that everything is in good working order. An annual inspection costs 1000-2000 ₽, and no routine maintenance is carried out.

I recommend concluding a contract with a third-party organization that has permission to service boilers. An annual contract costs about 15 thousand rubles. This amount includes maintenance and emergency visits. For comparison: if you contact such an organization for a one-time routine inspection, the visit will cost 8-10 thousand.

Boiler manufacturers do not recommend using antifreeze as a heat carrier.

It is poured in to protect the system from freezing, for example, if no one lives in the house in winter. When the temperature drops below zero, ordinary water will freeze and can damage the pipes.

In my experience, nothing terrible has happened to boilers because of antifreeze. I believe that by banning antifreeze, manufacturers are playing it safe, since they cannot be sure of its quality.
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