Timer running down too quickly

I have two timers running, they both trigger one another so when one reaches just below 0 it triggers the other to start until it reaches just below 0. The thing is the timers are running down extremely quick, although they are set at 30, they run down in a bout 5 seconds. Any ideas? I’ve tried setting the Time.timeScale = 1 but that changes nothing.

public static float timerOff = 30;
public static float timerOn = 0;
private bool isTiming = true;
// Use this for initialization
void Start ()
{
	Time.timeScale = 1.0f;
}

// Update is called once per frame
void Update ()
{
	if (isTiming == true)
	{
		timerOff = timerOff - 1 * Time.deltaTime;
		if(timerOff < 0)
		{
			isTiming = false;
			timerOn = 30;
		}
	}

	if (isTiming == false)
	{
		timerOn = timerOn - 1 * Time.deltaTime;
		if (timerOn < 0)
		{
			isTiming = true;
			timerOff = 30;
		}
	}

	print(timerOff + "off");
	print(timerOn + "on");
}

I suggest you to use

timerOff -= Time.deltaTime;

Instead

timerOff = timerOff - 1 * Time.deltaTime;