What should I do if there is no place for the water heater and it has to be installed in the toilet

Air can flow without carbon monoxide and carbon dioxide.

You can use a long impact drill bit to make a hole in the wall, and then pull a special line from the main air switch control box to connect to the toilet electric water heater through the hole in the wall, as for the ground wire, you can find a steel bar to hit 50 cm in the ground, it is best not to connect to the lightning rod ground wire, please accept.

It is safer to install in the kitchen, and it is easy to be toxic to gas when installed in the bathroom.

Yes, it should be installed outdoors, only strong exhaust can be installed indoors, and it also needs to be ventilated. Rooms that cannot be sealed are prone to poisoning.

Water heaters are generally not installed in the bathroom, the water is hot fast, in fact, it is not too fast, but there are many potential safety hazards, the humidity of the bathroom itself is large, which has a certain impact on the igniter, and the doors and windows are closed when bathing, the air is not circulated, if the installation is not standardized, carbon monoxide will occur and stay indoors, and carbon monoxide will be produced when the air is not in contact with the fire when the combustion is not sufficient, and it is easy to be dangerous in the case of poor ventilation.