Thermostat Question.

[sandman512]

Current set up; Lennox XC21 with a variable speed handler, TWO zones. Upstairs zone has Filtrete 3M50 WiFi stat in my bedroom. Since I don't leave the A/C on all day upstairs, I'll turn it on when need it. It kicks on, cools to desired temp; all good. Now the issue, when it hits in the desired temp, the stat kicks off. When the A/C calls for A/C(1' swing I believe) the unit goes on and then shuts off about 1 minute later. FWIW, same set up downstairs, not the same issue. Any thoughts? Thanks!

[timebuilder]

Current set up; Lennox XC21 with a variable speed handler, TWO zones. Upstairs zone has Filtrete 3M50 WiFi stat in my bedroom. Since I don't leave the A/C on all day upstairs, I'll turn it on when need it. It kicks on, cools to desired temp; all good. Now the issue, when it hits in the desired temp, the stat kicks off. When the A/C calls for A/C(1' swing I believe) the unit goes on and then shuts off about 1 minute later. FWIW, same set up downstairs, not the same issue. Any thoughts? Thanks!


Does the stat get any supply air blowing on it?

[sandman512]

Time,

There is a vent above it, I attempted to minimize the air coming out of it. Thanks!

[motoguy128]

Thermostats should be mounted at a return even if it's not the most convenient location. A remote sensor can be used on some thermostats if you want the controller in a different location. I'd ask that the installer move the thermostat. IMO, that's a big screw-up on their part. Poor attention to detail. IT makes me wonder what other details they didn't bother with.

A thermostat is stagnant air like in a corner with no air movement will cause a system to over condition and run too long. Place near a supply, it will short cycle and under condition and operate less efficiently.

[sandman512]

First, thanks for the replies, I appreciate it. The stat was actually originally in the hallway where the intake(I think that is what it is called). There are no vents in the hallway. So, we sleep with doors closed, so basically the A/C would just keep going because there is no "cold" air in the hallway. So, I asked to have it moved to bedroom, easiest spot in corner. So, what would be the best remedy for this situation. Thanks!!!
PS: Looking at the situation, maybe a one way register throwing the A/C away from the corner?

[timebuilder]

Time,

There is a vent above it, I attempted to minimize the air coming out of it. Thanks!

You need to have your contractor relocate the stat, so it monitors the temp of the general return air flow for that area.

[beenthere]

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[timebuilder]

First, thanks for the replies, I appreciate it. The stat was actually originally in the hallway where the intake(I think that is what it is called). There are no vents in the hallway. So, we sleep with doors closed, so basically the A/C would just keep going because there is no "cold" air in the hallway. So, I asked to have it moved to bedroom, easiest spot in corner. So, what would be the best remedy for this situation. Thanks!!!
PS: Looking at the situation, maybe a one way register throwing the A/C away from the corner?

You need to have a return in conditioned spaces. If you have decided to cut off the area that has a return from the conditioned space, you will have problems.

Consult with your contractor. You have now identified the problem. Let him help you to find a solution.

[motoguy128]

IF this is an attic installation, it might be easy enough to add a return in each room. I had the same problem in my house. Added 3 return grills. Now it's nicely balanced whether the doors are opened or closed.

The 2nd problem is that your pressurizing the rooms, so some air will be forced outside and that hallway is then negative and sucking in air form outside.

[sandman512]

IF this is an attic installation, it might be easy enough to add a return in each room. I had the same problem in my house. Added 3 return grills. Now it's nicely balanced whether the doors are opened or closed.

The 2nd problem is that your pressurizing the rooms, so some air will be forced outside and that hallway is then negative and sucking in air form outside.

There is a return in each room, just not the hallway. I assume pressuring the rooms by closing the doors? Thanks!

[sandman512]

Thermostats should be mounted at a return even if it's not the most convenient location. A remote sensor can be used on some thermostats if you want the controller in a different location. I'd ask that the installer move the thermostat. IMO, that's a big screw-up on their part. Poor attention to detail. IT makes me wonder what other details they didn't bother with.

A thermostat is stagnant air like in a corner with no air movement will cause a system to over condition and run too long. Place near a supply, it will short cycle and under condition and operate less efficiently.

Moto,

Sorry for the delay, busy kids, camps etc.... When you say a stat should be at the retur, can you define return? Because as of right now, it is mounted in my bedroom near a vent(return?). Thank you!