Ask Siri to set timer with alarm [duplicate]
Solution 1:
Sorry, looks like Siri pulls whatever is set in the Clock app for its timers. The only solution is to manually change it in Clock each time.
Solution 2:
It's a bit messy but you could leave your timer to sleep iPod and and use the 'set alarm for 45 minutes' or wake me up in 35 minutes to use your alarms instead they should always play out loud.