Tstat Remote Indoor Sensor--wire lost---Options?

JUGHNE

Elementary school steam heat for 4 classrooms and 2 entry's sensor cable was cut and not replaceable.

This is a 2 pipe system with steel finned tube convectors.

Remodeling contractors removed an office wall. Found a pipe coming out of the floor going up about 5' to a wall box. There were tstat cables spliced into the box going up into the ceiling. They didn't know what it was so just cut it off at the floor.

Now need control for boilers for this section of building.
The length was nearly maxed out as it was for remote indoor sensor connected to HW tstat in boiler room.

Going up overhead would almost double the length and grief.

Any suggestions for control.
Perhaps wireless remote sensor(s)?

Or a boiler control using ODT and return pipe temp?

This has been a difficult building to control with only 1 tstat location.
The teachers move around the classrooms on an annual basis.
Ladies of various ages and expectations of comfort.

The room with the sensor is currently occupied by the "cold lady" who finally complained her room was too warm when it was 90 degrees in the morning. I thought that would never happen for her.

Looking for suggestions.......thank you.

ratio

What stat/sensor? There's a few 10k wireless sensors around. If it's just a thermistor, you should be able to extend it quite far, as long as the wire resistance is miniscule compared to the sensor resistance. Google thinks 18 gauge wire has a resistance on a little over 6 ohms per 1000', so if your run is 4000' you're looking at a hair over 51 ohms (there & back). Not a big deal with a 10k sensor, but might be visible with a 3k sensor, IDK.

I'd probably try it.

EBEBRATT-Ed

C7189R Honeywell. Don't know if that will do what you need.

MikeAmann

The "cold lady" was having a hot flash.

tim smith

Tekmar 279 and their wireless indoor sensor and wired outdoor sensor? I think they have a wireless indoor sensor. I know they have wireless outdoor. Or as someone else noted, Honeywell redlink vision pro thermostat Th8320R1003 & C7189R sensor, maybe a couple sensors for averaging. Your existing may not be redlink and wont accept redlink wireless sensor. I wish the 279 had remote control over wifi but they don't. Another thing you can add to redlink is an internet gateway then be able to adjust remotely. Simple phone app, app is free to use. Honeywell TCC comfort app.
Good luck
Tim

JUGHNE

Thanks to all for your postings.

If we do go with new indoor sensor system it will not be in "cold lady" room.

Open to any other ideas also.

mattmia2

Is there something out there that is poe and networked that can just sit on a network drop?

JUGHNE

According to HW Resideo, the existing TH8321R1001 tstat Vision PRO series with RedLINK is the 2.0

version of Redlink that is compatible with HW C7189Red 1004 wireless indoor sensor.

They also say the sensor can transmit to an area of 6500 sq ft with a direct line of sight to 2400'.

The tstat itself is in the boiler room, which is a 1/2 basement, but tstat is mounted up at about floor grade height.

The old tstat air sensor is 77' away with 4 to 5 8" thick masonry walls in the straight line plus maybe 3 non-masonry walls.

The preferred new sensor location is 96' away with 5 8" masonry walls plus the 3 non-masonry walls.

Has anyone had success with this for ranges with these wall configurations?

pecmsg

JUGHNE said:

Elementary school steam heat for 4 classrooms and 2 entry's sensor cable was cut and not replaceable. This is a 2 pipe system with steel finned tube convectors. Remodeling contractors removed an office wall. Found a pipe coming out of the floor going up about 5' to a wall box. There were tstat cables spliced into the box going up into the ceiling. They didn't know what it was so just cut it off at the floor. Now need control for boilers for this section of building. The length was nearly maxed out as it was for remote indoor sensor connected to HW tstat in boiler room. Going up overhead would almost double the length and grief. Any suggestions for control. Perhaps wireless remote sensor(s)? Or a boiler control using ODT and return pipe temp? This has been a difficult building to control with only 1 tstat location. The teachers move around the classrooms on an annual basis. Ladies of various ages and expectations of comfort. The room with the sensor is currently occupied by the "cold lady" who finally complained her room was too warm when it was 90 degrees in the morning. I thought that would never happen for her. Looking for suggestions.......thank you.

Hold the demolition crew responsible. 

JUGHNE

This only one of 3 things they messed up, not the demo crew but the electrician.

Looking at Redlink wireless indoor sensors as stated above.

Any experience with the signal traveling thru walls?

mattmia2

JUGHNE said:

The old tstat air sensor is 77' away with 4 to 5 8" thick masonry walls in the straight line plus maybe 3 non-masonry walls.

My ham side would say propagation through multiple concrete walls is usually poor but i don't have experience specifically with that product. Is the floor also concrete? Could you get a receive under the floor if not?

JUGHNE

School rooms are slab on grade. Boiler room 1/2 floor lower.

Tstat (receiver) actually about at level of the slab.

ratio

RedLINK pairs with a lower power than it operates at normally, so if you do get it to pair it should keep on working.

Something else to consider would be an EIM, as they can have a wired range extender (THM4000 IIRC), located in a spot with better connectivity. You might be able to reuse the stat, although I seem to recall there is an incompatibility with earlier parts. Also, the latest version of the wireless indoor sensor, the one with the motion detector, only works with the T series stats.

JUGHNE

The wireless remote temp sensor is on the way.

Will try it and report back.