HVAC units contain various expensive materials and precious metals that are prone to theft. Protect your home’s air conditioning unit from tampering with various air conditioner theft alarm systems and products. Items include a dual tone outdoor or indoor siren with an option for a Volt DC Relay to add another siren. Tampering switches detect excessive vibration or movement of the condensing unit to notify owners. Condensing Unit alarm systems sound a loud siren and trigger a central alarm, phone dialer, or other device while monitoring up to four units with one panel.