Any thermostat experts?

[bowhuntr311]

Hey guys,

I ran into a "snag", Im guessing this is just simply a programming error or maybe I need a different stat?
The configuration shouldnt matter in this case but I'll run through it to save the questions.
In my shop I have 2 zones. A radiant floor and a 100K hanging water-to-air modine style heater. The fan on it is powered by the same circuit as the pump.....so really all we care about is 2 zone; controlled by a 2 zone Taco controller. My goal is for the radiant floor heat (zone 1) to be the primary source and when I turn up the heat more than X degrees then zone 2 kicks in.

I have a Honeywell T5 wifi thermostat. Heating options are boiler, conventional, heat pump w/aux heat. The boiler options have a stage 1,2 but no way to differentiate between which stage does what/when. Only has "cycles per hour." Stage 1 seems to be the primary but 2 kicks on when ever it seems to want.

Any suggestions?

 

[Specracer]

Have you confirmed that the power supply that is supplying the t-stats has enough current? We have seen this many times, there is enough power to light up the t-stats, they look like they are working, but they are flaky.

 

[shadycrew31]

Hey guys,

I ran into a "snag", Im guessing this is just simply a programming error or maybe I need a different stat?
The configuration shouldnt matter in this case but I'll run through it to save the questions.
In my shop I have 2 zones. A radiant floor and a 100K hanging water-to-air modine style heater. The fan on it is powered by the same circuit as the pump.....so really all we care about is 2 zone; controlled by a 2 zone Taco controller. My goal is for the radiant floor heat (zone 1) to be the primary source and when I turn up the heat more than X degrees then zone 2 kicks in.

I have a Honeywell T5 wifi thermostat. Heating options are boiler, conventional, heat pump w/aux heat. The boiler options have a stage 1,2 but no way to differentiate between which stage does what/when. Only has "cycles per hour." Stage 1 seems to be the primary but 2 kicks on when ever it seems to want.

Any suggestions?

What you have is a basic thermostat with internal programming that you most likely aren't going to be able to access. The programming could look something like, "if primary heat runs for 5 minutes with 1* increase in space temp then turn on secondary heat".

To the best of my knowledge you cannot access or change these parameters in this particular thermostat.

You can however do some trial and error and try to figure out the time delay.

Just out of curiosity what are the settings configured as in the system setup options? I would assume #205 is set to option 5 and #221 is set to 1?

 

[bowhuntr311]

What you have is a basic thermostat with internal programming that you most likely aren't going to be able to access. The programming could look something like, "if primary heat runs for 5 minutes with 1* increase in space temp then turn on secondary heat".

To the best of my knowledge you cannot access or change these parameters in this particular thermostat.

You can however do some trial and error and try to figure out the time delay.

Time delay is most likely the default. It seems like 5 min or so if it doesnt come up 1 degree then stage 2 kicks in for a very short time to bring it up that small amount.

Just out of curiosity what are the settings configured as in the system setup options? I would assume #205 is set to option 5 and #221 is set to 1?

#205 is set to option and #221 is set to 2. When I do a system status check. stage 1 and 2 are controlled correctly.

 

[acmikee]

are you planning on running the air handler as a 2nd stage or only part time. if only part time then I would install a second stat to open the HW valve on a call for heat and add a heat sensor attached on the coil to only cycle the fan when the coil is hot

 

[shadycrew31]

Time delay is most likely the default. It seems like 5 min or so if it doesnt come up 1 degree then stage 2 kicks in for a very short time to bring it up that small amount.



#205 is set to option and #221 is set to 2. When I do a system status check. stage 1 and 2 are controlled correctly.

#205 is set to what option? When you say stage 1 and 2 are controlled correctly are you referring to stage 2 as the hanging heater or is your radiant heater two stages?

 

[danski0224]

Hey guys,

I ran into a "snag", Im guessing this is just simply a programming error or maybe I need a different stat?
The configuration shouldnt matter in this case but I'll run through it to save the questions.
In my shop I have 2 zones. A radiant floor and a 100K hanging water-to-air modine style heater. The fan on it is powered by the same circuit as the pump.....so really all we care about is 2 zone; controlled by a 2 zone Taco controller. My goal is for the radiant floor heat (zone 1) to be the primary source and when I turn up the heat more than X degrees then zone 2 kicks in.

I have a Honeywell T5 wifi thermostat. Heating options are boiler, conventional, heat pump w/aux heat. The boiler options have a stage 1,2 but no way to differentiate between which stage does what/when. Only has "cycles per hour." Stage 1 seems to be the primary but 2 kicks on when ever it seems to want.

Any suggestions?

A 2 stage thermostat will typically kick on the second stage when there is more than a (approx) 2 degree difference between the indoor temperature (lower in this case) and the desired setpoint (higher in this case).

A 2 (or more) zone thermostat is not the same as a 2 stage thermostat. This would interface with a zoning panel, sending the signal from multiple thermostats to a single piece of heating/cooling equipment.

I suspect that the simplest solution would be 2 thermostats.

One thermostat would be the main one for the radiant floor heat.

The other would be for the hanging heater. When you bump up the desired setpoint on that thermostat, your hanging heater would turn on. One possible drawback is then the in floor heat would turn off as the air temperature rises, unless there is a sensor in the concrete.

Your Taco controller becomes the thermostat zoning panel.

I would not be surprised if your desired "stage 2 after x degrees of change" could be accomplished with building automation controls, but that would be pretty expensive to implement.

 

[shadycrew31]

A 2 stage thermostat will typically kick on the second stage when there is more than a (approx) 2 degree difference between the indoor temperature (lower in this case) and the desired setpoint (higher in this case).

A 2 (or more) zone thermostat is not the same as a 2 stage thermostat. This would interface with a zoning panel, sending the signal from multiple thermostats to a single piece of heating/cooling equipment.

I suspect that the simplest solution would be 2 thermostats.

One thermostat would be the main one for the radiant floor heat.

The other would be for the hanging heater. When you bump up the desired setpoint on that thermostat, your hanging heater would turn on. One possible drawback is then the in floor heat would turn off as the air temperature rises, unless there is a sensor in the concrete.

Your Taco controller becomes the thermostat zoning panel.

I would not be surprised if your desired "stage 2 after x degrees of change" could be accomplished with building automation controls, but that would be pretty expensive to implement.

Yeah a building automation controller would do the trick. I program and troubleshoot some of the oldest and newest commercial controllers on the market. Residential isn't my strong suit but i dabble as a hobby in my home.

It could be possible with two relays,a temp sensor, and a hub like smart things to achieve the result the OP us looking for. But just having two tstats would be infinitely easier.

 

[bowhuntr311]

Im sure the 2 T-stat setup would be the easiest. And I may go that route if I decide my current setup isnt desirable. I was just hoping someone had a simple answer I was missing.
Through Christmas I did some testing and realized it only takes just a few minutes to bring my air temp up a significant amount with the hanging heater. (16min I can raise it 20 degrees)

I'll have to do some testing to see what triggers stage 2. It seems like it could be a 2 degree change.

#205 is set to what option? --- Set to "Boiler"

 

[American Locomotive]

You might give "Heat pump w/ auxiliary heat" a try. I think the problem is the radiant heat has a very large hysteresis between when the call for heat is made, and the room temperature actually starts rising.

 

[shadycrew31]

You might give "Heat pump w/ auxiliary heat" a try. I think the problem is the radiant heat has a very large hysteresis between when the call for heat is made, and the room temperature actually starts rising.

Typically that will turn the heat pump off and only run the aux heat. Which I dont think would work in his application.

 

[bowhuntr311]

Typically that will turn the heat pump off and only run the aux heat. Which I dont think would work in his application.

I did try that, because the heat pump has some temp differential settings. Stage 1 never engages, stage 2 comes on as Aux heat.

I played with it a touch last night while I organizing. It appears a 1 degree increase will only engage stage 1 but 2 degrees will cause stage 2 to kick in after a 2-3 min.

Thanks for the help everyone.

 

[shadycrew31]

I did try that, because the heat pump has some temp differential settings. Stage 1 never engages, stage 2 comes on as Aux heat.

I played with it a touch last night while I organizing. It appears a 1 degree increase will only engage stage 1 but 2 degrees will cause stage 2 to kick in after a 2-3 min.

Thanks for the help everyone.

Glad you got it sorted! Tstats can be a pain in the *** when you cant see or control their logic.