Thermostat for 100 yr old house, heat only - trying to avoid pipes freezing, chilly arrivals & get flood alerts this winter!

Just came home with an ST hub, one water sensor and one multi sensor. We haven’t picked a thermostat yet but are leaning towards a 2gig z wave based on what I’ve read on here. We don’t really need the programable or learning capabilities of a smart thermostat just something that can give us warnings and adjust from a distance. Here are our stats & what we’re trying to accomplish:

-1888 house, 1700 sq ft

-hot water radiators in almost ever room - no AC (got a Frigidaire smart AC unit and it’s been great - not ST compatible as far as I know, oh well)

-no Neutral wire on the current thermostat but we replace the battery on a strict schedule. We have a R and W wire as do most older homes.

our goals:

-We’re not here quite as much during the winter and we don’t want to come home to frozen (or burst) pipes or a popsicle of a cat after a few days away (don’t worry he has a “smart” feeder he loves & he lives at his city pied a terre dmost of the winter - he might be a little spoiled). Last year during some extremely cold days the pipes froze with the heat around 70 and we’d like to be able to give the heat an extra boost if it’s going to be very cold. We’d also like a heads up if something is wrong - system is down, power/internet is out etc and we need to make a beeline home.

-We leave the heat around 68 when we’re not around and we’d like to be able to turn up the heat before we get home

-We want a warning if the basement is flooding after a heavy rain (hence the water sensor)

We figured one of each sensor would be enough to start experimenting with but we have yet to choose a thermostat. Any advice would be very welcome as far as thermostats, water or temperature sensors. Thanks! Setting up what we bought tonight!

One thing I have done is place a couple of thermal sensors in the cooler parts of the house. You can use one of these to bump up the thermostat if they get below a threshold. Mine just send me an alert if the greenhouse or pantry get too cold.
As mentioned elsewhere on the boards, using AT directly to control the heat is a bad idea, however using them to set the thermostat higher would be OK.
I use the 2gig thermostat (interfaced with a millivolt system) and am happy with it, price and performance. Be sure what type of system you have, the 2gig is either 24vac or millivolt. some older systems are 110/220vac and you will need a relay system to make it right.

Glenn, I’m very jealous of your greenhouse. One of my fantasies for this
system is definitely an eventual greenhouse!

I think we’re on the same page as far as ST controlling the heat. We were
planning on using ST as more of an alert system to know if the heat needed
to be changed rather than automating it. Do you link the ST & 2gig at all?
Do you just use ST in order to get alerts from your 2gig sort of using it
like another sensor? or do you just use them separately? I’m wondering if
that’s a better option as far as confusing too many systems and risking mid
winter shutdowns when we’re away & ST problems resulting from short term
power outages.

As far as power I was planning on just using batteries and changing them on
a schedule as we’re just not ready to do a major electrical overhaul here
and there are many questions as to what has been done (and if it’s been
done right) in the past. The less connected to our wonky power the better.
Do you see any reason that we would have to connect this to power? I’m
getting mixed responses from people I’ve talked to about this but we’ve
never had issues with our battery operated thermostat before. In fact we
sort of enjoy marking the passing of the seasons with our tradition of 4th
of July and xmas checking and replacing of the batteries!

The ct100 does all of the stove control by itself. ST connects to it to change the setpoint and turn it off when the doors are open.