1. Weight

The heavier the better. Ordinary one-piece toilets are about 25kg and the good ones are about 50kg. The heavy one-piece toilet with high density is usually superior in quality. As for simple method for testing the weight of it, you can take up the tank cap to weigh its weight in your hands.

2.     Water outlet

The one-piece toilet with one sewage hole is the best, but the number of many brands’ sewage hole is about 2-3 (according to different caliber), affecting the impulsive force to a large extent. The water outlet in the washroom can be divided into down drain and horizontal drain, so you shall measure the distance from the center of the lower water outlet to the wall after the tank, then buy the one-piece toilet of the correct model to match the distance, otherwise, the toilet cannot be installed. The water outlet of the toilet with horizontal drain shall be of the same height with the horizontal water outlet(or the slightly higher height would be better), which can guarantee the unblocked sewage discharge.

3.     Caliber

Sewage pipes with large caliber and glazing internal surface are less prone to stick dirty. In addition, the one-piece toilet of this kind can blow off the sewage quickly and powerfully, preventing the block in an efficient way. Testing method: put your hand in the outlet of the one-piece toilet, the one can hold your palm is the best.

4.     Tank

It is not easy to realize the leakage in the storage tank of the one-piece toilet unless there is obvious dripping sound. The simple checking method is to drop blue ink into the tank and to check if there is blue water leaking out from the toilet after mixing up. If yes, it indicates that the toilet is damaged. It is good to recall here that the tank’s height of the toilet, which is relatively high, usually has a strong impulsive force.

5.     Flushing

The flushing way really matters. And it can be classified into wash-down type, rotary siphon type, vortical siphon type and siphon-jet type. Furthermore, choosing different drainage way shall also be noted: wash-down type, siphon wash-down type and siphon vertical type, etc. The water injection amount of wash-down type and siphon wash-down type is about 6L. They are superior in sewage discharge but produce large sound when flushing; while the swirling type has a good mute effect but demands great water consumption.