Owing to the fact that the vertical one-pipe-series-loop heating system for existing house in China is not closed loop system,the metered heating can be realized only by heat cost allocator.

It is point out that the determination of heat rates, collection of heat tariff and mode of heat metering for metered heating system are related each other.

A study on the structure, main devices and working principle of a variable differential calorimeter used for metered heating is made.

Discussion on several problems during implementing warm heating meterage;

It must meet the requirements of new heat users for self-regulating indoor temperature,and ensure that existing heat users not affected by flow rate change of new heat users when an individual metered heating system is connected to an existing heat-supply network.

The hardware structure and principal program flow of the monitor for individual metered heating are discussed,and an introduction to its functions is given.

By calculating the effect of indoor temperature variation on heat source load under conditions of different radiator, supply and return water temperature , reference data on determining the heat source load after individual metered heating for residences are given.

This paper suggests that heating metering and charging should be practised first in enterprises,and supported by technical and economic evibences.