Switch/Group changed Rule not working as expected

Setup, Configuration and Use Beginners
11

I explored Timers a bit more, and searching the forums came upon Expiry Timers from a great post from @rlkoshak here Design Pattern: Expire Binding Based Timers

But my timer isnt expiring (sending the OFF command)

Any ideas why?

items

/* HW Countdown Timer , even set to 1 minute to interrupt the 60 minute counter. Didnt work */
Switch i_HVAC_HW_Timer_Switch { expire="1m,command=OFF" }
Number i_HVAC_HW_Counter "Hot water timer" <clock-on> (g_HVAC) 
/* Sitemap switch */
Switch	i_HVAC_HW_Switch "HW On/Off" <switch>	(g_HVAC, g_HVAC_Switch)	{channel = "zwave:4849599d:t_Zcontroller:node3:swtich_binary1"}

Rule

// Global var count can be updated from any rule
var count = 0 

rule
    // Start timer when HW switch set to ON
    "HVAC_HW_Start_Timer"
when
    Item i_HVAC_HW_Switch changed to ON
then
    // Start expiry timer
    logInfo("HVAC_HW.rules", "HOT WATER countdown timer STARTED by rule")    
    i_HVAC_HW_Timer_Switch.postUpdate(ON)
    count = 60
    while (count >= 0) {
        i_HVAC_HW_Counter.postUpdate(count)
        count = count - 1
        // Sleep for one minute
        Thread::sleep(60000)
    }
    logInfo("HVAC_HW.rules", "HOT WATER countdown updates finished")    
    i_HVAC_HW_Timer_Switch.sendCommand(OFF)
end


rule 
    // When timer has expired
    "HVAC_HW_Timer_Expired"
when
    Item i_HVAC_HW_Timer_Switch received command OFF
then
    // Set counter to zero - will occult the timer value on the sietmap
    logInfo("HVAC_HW.rules", "HOT WATER countdown timer EXPIRED")    
    count = 0
    //Expiry on switch doesnt send the "OFF" command so force it ??
    i_HVAC_HW_Switch.postUpdate(OFF)
end


rule 
    // Cancel timer if HW switch set to OFF by user
    "HVAC_HW_Cancel_Timer"
when
    Item i_HVAC_HW_Switch changed to OFF
then
    if (i_HVAC_HW_Timer_Switch.state == ON) {
        // Interrupt timer and force expiry
        logInfo("HVAC_HW.rules", "HOT WATER countdown timer INTERRUPTED by rule")    
        count=0
        i_HVAC_HW_Timer_Switch.sendCommand(OFF)
    }
end

On the GUI, when I select HW (i_HVAC_HW_Switch) to ON, the events fire and the timer is started and the countdown appears in the GUI, but the expiry on the Switch i_HVAC_HW_Timer_Switch { expire=“1m,command=OFF” } does not “fire” the OFF command so that the rule
HVAC_HW_Timer_Expired is executed.

Any ideas?