Thermostat

[Frank Angel]

When they get it right, it can all work beautifully; when they don't you get what we got in our Film Department -- top floor of a two story building with two 300 seat screening rooms, a large lobby two 25 station Apple editing suites, fourteen classrooms, a conference room, two filming stages and an equipment room....NONE of which EVER were the same temperature. We frequently need to move a class from an intolerably cold classroom to one that was at a decent temperature. It would be common to read temperature differences of a full 15° between rooms, some right next to each other. Professors would get rightfully angry when they'd have to teach in a classroom that was 80 and more. College Facility engineers would come by and get up into the hang ceilings & mess around for half a day and nothing would ever come of it. Some times whatever they did would mitigate the problem but it would simply move it to other rooms. One of the confess, that they really couldn't figure it out other than mechanical parts were 20 years old and didn't hold the positions they were set at. And of course the company no longer existed anyway so no replacement parts available. The rushing air sound from the vents was so intense that many times the Sound Mixer would use that room to record sound for a scene in a windy landscape it was so loud. Kids would get wool inulations sheets and gaffer it up over the vent when shooting a scene when they needed quiet. I just retired last July and one of the things I wish I had been able to do was to grab a 16 foot ladder and get my head up into that hang ceiling and see what contraptions they had in there to control the HVAC -- would have been ab interesting look-see..

[Ryan Gallagher]

On the load shedding topic, Austin has that program too for smart meters, but I learned that being in a condo with sub-metering and billing done by a 3rd party, that there is no way for the 3rd party to apply the discount!! So much for that, never opted in.

[Harold Hallikainen]

On smart meters and load shedding, it seems to me that the thermostat is a much better choice. The smart meter would need a big relay (or SSR) to do load shedding. And, it would shut down everything after the meter (a whole building). The thermostat load shedding would only shed the load it controls (typically cooling). And no big relay is required. And having it connect through the customer's existing WiFi makes communications free (no mesh network and gateway required as is required for the smart meters).

On the building with large temperature differences between rooms, I'm liking the hot/cold water circulation system of my college dorm room that I posted about earlier. Independent control in each room.

[Ryan Gallagher]

On smart meters and load shedding, it seems to me that the thermostat is a much better choice. The smart meter would need a big relay (or SSR) to do load shedding. And, it would shut down everything after the meter (a whole building). The thermostat load shedding would only shed the load it controls (typically cooling). And no big relay is required. And having it connect through the customer's existing WiFi makes communications free (no mesh network and gateway required as is required for the smart meters).

On the building with large temperature differences between rooms, I'm liking the hot/cold water circulation system of my college dorm room that I posted about earlier. Independent control in each room.

Apologies I think I miss-spoke. I was referring to my residential smart thermostat... although I'm sure smart meters are involved somewhere down the chain too. I'm too used to measuring things with meters, and not stats. ;-)

[Mark Gulbrandsen]

Must be magic. I've got a thermostat in the theater that has a digital readout on it and it's been working for 15+ years and I don't even know if it has a battery in it.

If there is a battery it's likely just to illuminate the readout. That's how mine is.

[Tony Bandiera Jr]

When they get it right, it can all work beautifully; when they don't you get what we got in our Film Department -- top floor of a two story building with two 300 seat screening rooms, a large lobby two 25 station Apple editing suites, fourteen classrooms, a conference room, two filming stages and an equipment room....NONE of which EVER were the same temperature. We frequently need to move a class from an intolerably cold classroom to one that was at a decent temperature. It would be common to read temperature differences of a full 15° between rooms, some right next to each other. Professors would get rightfully angry when they'd have to teach in a classroom that was 80 and more. College Facility engineers would come by and get up into the hang ceilings & mess around for half a day and nothing would ever come of it. Some times whatever they did would mitigate the problem but it would simply move it to other rooms. One of the confess, that they really couldn't figure it out other than mechanical parts were 20 years old and didn't hold the positions they were set at. And of course the company no longer existed anyway so no replacement parts available. The rushing air sound from the vents was so intense that many times the Sound Mixer would use that room to record sound for a scene in a windy landscape it was so loud. Kids would get wool inulations sheets and gaffer it up over the vent when shooting a scene when they needed quiet. I just retired last July and one of the things I wish I had been able to do was to grab a 16 foot ladder and get my head up into that hang ceiling and see what contraptions they had in there to control the HVAC -- would have been ab interesting look-see..

It's most likely one of the older pneumatic systems with the air powered t-stats. If you change the setting and the stat hisses, that's exactly what it is. Those old systems were always a nightmare and never could regulate the air temps that well.

And trust me, you don't ever want to look above the ceiling..like they say, it's like how sausages are made...you don't want to know.

[Tony Bandiera Jr]

If there is a battery it's likely just to illuminate the readout. That's how mine is.

Maybe. There are (were?) a lot of stats that had to have the battery to actually operate. But also there are a lot just as you describe.

[Mark Gulbrandsen]

Maybe. There are (were?) a lot of stats that had to have the battery to actually operate. But also there are a lot just as you describe.

Mine still works the batteries are dead. Am pretty sure they are supplied power from the actual furnace. Thermostats can have 4 wires, or 6 wires.

[Tony Bandiera Jr]

Mine still works the batteries are dead. Am pretty sure they are supplied power from the actual furnace. Thermostats can have 4 wires, or 6 wires.

Correct. I forgot to mention the power wires some stats provide (I think they are "R" and "C", "R" is almost always red, but the "C" wire color seems to change depending on the installer's mood.)