How to update sensor temperature value from Home Assistance?

Hi All,
I am struggling from few days to figure out how to migrate my DIY home controller (Arduino Mega 256) from OpenHub to Home Assistance. This arduino device is connected to Home assistance by USB Serial port with MySensor Gateway. I have switches, relays, temperature sensors and HAVC. Everythink works fine except my floorheat HAVC. I Have need to update V_TEMP on HAVC from Home Assistance (current temperature is provided from different device [RFLINK]).
I not see any Climate service which provide me possibility to set v_temp in havc device. The same thing I see in simple sensor V_TEMP.
Mysensor API provide possibility to update sensor V_TEMP so is it possible in Home Assistance?
In OpenHub I am able to do that without problem (update current value in OpenHub Item immediately send value to sensor)