How to Connect a Water Heater via a Bathtub Faucet
I don't recommend connecting the boiler this way; the diverter isn't designed for this type of use; it's only temporary and unreliable. But if you really want to, you can do it at your own risk.
What did we save here? A pair of diverters cost us 500 rubles.
A pair of taps, a pair of tees, and 3/4" to 1/2" adapters would have cost 1,500-2,000 rubles, and the connection labor would have been half as expensive. The bonus of this connection is that it can be disassembled with just an adjustable wrench, but for the initial assembly, you'll need a screwdriver and a 3mm drill bit. In this particular situation, the apartment is sublet, and after the owner hands it over, the tenant takes the boiler for themselves.