Boiler and safety
A boiler that has a loss of feed water and is permitted to boil dry can be extremely dangerous. If feed water is then sent into the empty boiler, the small cascade of incoming water instantly boils on contact with the superheated metal shell and leads to a violent explosion that cannot be controlled even by safety steam valves. Draining of the boiler can also happen if a leak occurs in the steam supply lines that is larger than the make-up water supply could replace. The Hartford Loop was invented in 1919 by the Hartford Steam Boiler and Insurance Company as a method to help prevent this condition from occurring, and thereby reduce their insurance claims
Źródło: https://en.wikipedia.org/wiki/Boiler#Safety
Boiler exlosion?
A boiler explosion is a catastrophic failure of a boiler. As seen today, boiler explosions are of two kinds. One kind is a failure of the pressure parts of the steam and water sides. There can be many different causes, such as failure of the safety valve, corrosion of critical parts of the boiler, or low water level. Corrosion along the edges of lap joints was a common cause of early boiler explosions.
The second kind is a fuel/air explosion in the furnace, which would more properly be termed a firebox explosion. Firebox explosions in solid-fuel-fired boilers are rare, but firebox explosions in gas or oil-fired boilers are still a potential hazard.
Źródło: https://en.wikipedia.org/wiki/Boiler_explosion
Checking the meter water
Hydraulic works carried out in a domestic boiler are mainly related to the installation of the boiler and the foundation and checking correct operation of the water meter. Counter water must be installed by an authorized plumber who will also make his sealing. In case of any doubt, will also check a meter on the water especially when he suddenly began to show much higher water consumption than before. Usually installed in the boiler room is also a boiler, water heater. After its installation, the current home plumber, could also make his first start and check thanks to proper operation. Household members will be happy with such a solution, especially if the first use of the gas boiler.