I have an electric furnace that is blowing cool air. It comes on and goes off according to the thermostat so that appears to be working but when it comes on the air coming out of the vents is quite cool and it won't heat the house past 16 Celsius. Is it possible that the element is partially unfunctional?

It is possible that

One of the heat sequencers or relays are defective.

One or more of the heaters is defective.

You can only tell by the use of a electric meter with the knowledge of exactly what you are doing. Also make sure that all circuit breakers for the unit are turned on.