The video is about a person trying to fix a heating system in their house that has stopped working. The system uses a Combi heater, which heats water for showers and also for baseboard heaters. The person discovers that the problem lies in the electric valves that control the flow of hot water to different zones in the house. The valves are controlled by thermostats, but the person suspects that the thermostats might be in a power-saving mode.
After investigating, the person finds that two of the five electric valves are not working properly. They take apart one of the valves and discover that the motor is not turning properly due to friction, and the other motor has a disconnected wire.
The person decides to test the motors and discovers that they are low-speed, low-torque motors that use gears to increase torque. They also find that the motors are rated for 24 volts but are actually receiving 29-30 volts, which might be causing them to fail.
The person decides to replace the motors with new ones and finds a knockoff version for $37. After replacing the motors, they test the system and find that it is working properly. They also discover that the transformer that converts 120 volts to 24 volts AC is not regulated, which means that the voltage can drop under maximum load.
Overall, the video is a DIY tutorial on how to troubleshoot and fix a heating system, with a focus on electrical engineering and plumbing.
Here are the key facts extracted from the text:
1. The author has a Combi heater that heats water for showers and baseboard heaters.
2. The Combi heater is a tankless device that takes a small footprint to do its work.
3. The author's baseboard heaters are like radiators that hot water runs through to create heat.
4. The hot water from the Combi heater goes to a magic device that splits into five zones in the house.
5. The hot water returns to the other side of the heater, creating a closed loop.
6. The author's thermostats are Nest smart thermostats that can be controlled with an app.
7. The thermostats control electric valves that are controlled by signals coming from the thermostats.
8. The valves are controlled by AC voltages, specifically 29 volts AC.
9. The author's motor is a low-speed, low-torque motor that uses gears to increase torque.
10. The motor is rated for 24 volts AC, but the author measured 29-30 volts AC across it.
11. The motor has a coil resistance of around 22 ohms and an inductance of almost 80 milliHenry at 100 Hz.
12. The motor has a total impedance of around 37 ohms at 60 Hz.
13. The motor is rated for 650 milliamps of continuous current, resulting in 15.5 watts of apparent power.
14. The author replaced the old motors with new ones that seem to be perfect replicas.
15. The new motors are rated for 24 volts AC and have the same specifications as the old ones.
16. The author installed the new motors and they seem to be working fine.
17. The author found an unregulated power supply that converts 120 volts to 24 volts AC.
18. The power supply measures almost 31 volts AC, which drops to 26 volts under maximum load.