Explanation for cold/warm switch in pid_loop

[elf02]

Can you please explain the warm/cold logic:

silvia-pi/silvia-pi.py

Lines 152 to 168 in 54de212

	if avgtemp < 100 :
	lastcold = i
	if avgtemp > 200 :
	lastwarm = i
	if iscold and (i-lastcold)*conf.sample_time > 60*15 :
	pid = PID.PID(conf.Pw,conf.Iw,conf.Dw)
	pid.SetPoint = state['settemp']
	pid.setSampleTime(conf.sample_time*5)
	iscold = False
	if iswarm and (i-lastwarm)*conf.sample_time > 60*15 :
	pid = PID.PID(conf.Pc,conf.Ic,conf.Dc)
	pid.SetPoint = state['settemp']
	pid.setSampleTime(conf.sample_time*5)
	iscold = True

iswarm will always be false. Should the pid values for the warm state be set only once when avgtemp >= 100?

Thank you :)