Gas-fired steam heat - any preferred thermostats, or are they all the same?

Jim_NY

Not yet in heating-season but saw thermostat had a blank clock/temperature display...the AAs had not just leaked, but flowed onto the PCB and had visibly corroded the conductive surface of the negative battery terminal.
It's a 10-12 yr old Honeywell TH4110D1007 (Pro 4000) thermostat with just two wires used (gas-fired steam).
Expect I'll clean the PCB off and kludge the terminal to conduct well enough. But if the thermostat doesn't work reliably, and need to replace, curious if people here actually have a preference.
Simple would be fine, as the main user who would adjust for comfort would be a senior. (Who not only thinks the old mercury mechanicals were better, but also insists that no-matter the thermostat, it was the absolute best in this building back when the steam-heat was coal-fired.)

jesmed1

Here's a previous discussion on the subject. It's almost 10 years old, but the principles are the same. The main discussion is about the optimum number of cycles per hour for steam, so you'll want to be able to set that on whatever Tstat you opt for.

https://heatinghelp.com/systems-help-center/best-thermostats-for-steam-systems/

Jamie Hall

Honeywell has a p[erfectly good like for like "upgrade" to what you have which would probably work just fine.

Jim_NY

Appreciate the comments.
> ... a previous discussion on the subject
Interesting read. The installer way-back had never mentioned cycling. Found the "installer setup" online and see that it can be viewed and adjusted. (FYI it says 5 is factory default, and suggests 1 for steam, 3 for hot water, and 6 for electric.)
> Honeywell has...like for like
Yes, see that the the replacement-model is the T4 Pro TH4110U2005 with a new universal wall-plate. (Some retailers seem to stock older style variants which would allow reuse of the current wall-plate.) It's curious that the reviews at HoneywellHome are all so consistently negative (for non-WiFi models) - but not so bad at retailer websites.

Mad Dog_2

The old Honeywell T 87 (With Mercury) stopped being made about 15 yrs ago? Shame shame.  That was the Gold Standard for Steam Heat.  Simple.  Since, they are rare to find, work with what you have.  The Newer T 87 is ok  Mad Dog 🐕 

Jim_NY

Wonder if the current T87 is vintage-analog on the outside and digital-electronic inside? Can't tell from the pics. (Like currently-sold flip-phones are running camouflaged smart-phone operating systems.) Used to see those everywhere, but the long-time resident only remembers rectangular thermostats here, over the years.

Anyway, finished cleaning and drying the PCB, and did successfully kludge the (-) terminal. Put in a couple of NOT-alka-leaky batteries, and seems to be functioning, other than a minor weakening of a couple of LED segments at the left of the display. And yes it's at all factory defaults including 5 CPH. Guess I should reduce that number to 3 or 2 or 1 ???

Jamie Hall

Yes. Steam heat will be much happier set to 1 -- and probably save some fuel.