I have had this system https://www.monnit.com/ in for 4 years & it works great. I think the cost is reasonable. I use the cellular interface but if you have a PC running you can do it cheaper with just buying the sensors. It will text/ email or both as many people as you want. I run temp sensors for floor heat, IBA heat, tank high/low water, power out, low air pressure and more. They have all kinds of sensors you can adapt to anything in our business. After the initial cost of the sensors & cellular interface I pay $10.00 a month for monitoring. PC monitoring is free. Worth it for my peace of mind & saved my butt more than a few times, along with cameras to verify(maybe the leak isn't a flood and can wait) to make sure you don't waste a trip to the wash. Check it out easy to set up.
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