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tgcrosle 12-03-2009 09:00 PM

Strange Thermostat Issue, Hot=Cold PLEASE HELP
Hello, thanks in advance for any help offered.

I bought (several) a new digital thermostat, installed it, and have the strangest issue.

Firstly. I live in a condo building 5 yrs old with baseboard hot water heating.

After buying a honeywell digital thermostat for this type of heating and installing it the heater would turn off when it's below the 21C temperature setting and it would turn on only if I lowered the setting to below room temperature. Instead of, you know, turning on when it gets cold it simply remains cold. If I turn the setting to below 21 the heater clicks on, but then since the setting is now below room temperature, the heater will remain turned on forever. A normal thermostat would turn off when Room Temp> thermostat setting.

Essentially the thermostat was doing the EXACT OPPOSITE thing it's supposed to do. It would turn the heater on when it should be turning the heater off and vice versa.

Logically I returned the thermostat and got a different brand, still designed for hot water baseboard heaters. And the SAME THING happens. Retunred it and got the last thermostat they had that was compatible with baseboard hot water systems. SAME ISSUE.

I tried switching the wires connecting to the thermostats. Nothing. (there's two white wires coming out of my wall)

I've ensured all the settings are correct and ensured it's in the "heat" mode. Nothing.

After getting frustrated I bought a newer version of the same old analogue thermostat I had before (the coiled metal ones where you physically move the knob) and guess what... SAME FREAKING PROBLEM!!!

Now I know I am definitely not the problem (please tell me I am the problem rather than having some major issue here)

It's like the wiring is all mixed up no matter what thermostat I use. AND THEN I suspect the builders may have realized they messed up the wiring but instead of fixing the wiring they simply tampered with the original thermostat and reversed the metal coil so that it hot = cold.

Literally I compared my thermostat with the same analogue one I bought from the store and everything looks reversed. Mine doesn't actually have numbers on the plastic cover but instead of moving the knob to the right to turn up the heat like the store bought one, for some reason I have to move mine to the left.

Calling the builder was, as usual, useless. What's also weird is that if I remove the thermostat from the wall and don't do anything else. The heater turns on!? Is that normal??? Doesn't seem normal to me.

FOR THE LOVE OF GOD! HELP MEE!!! Or please tell me I am making some fantastic beginner's blunder.

Thank you,


tgcrosle 12-08-2009 09:51 PM

according to this my zone valve (Honeywell V8043d1080) in my heating system is a "normally open" type valve which apparently requires "A reverse acting thermostat is required to control a normally open valve." Why they set it up this way I don't know...

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