As a for instance, in the installation instructions for the Infinity control, under hybrid heat, the example given shows a furnace lockout at >30*F and a HP lockout set for I have no idea what the furnace and the HP do in response to the settings on this page.

Per your suggestion, would both the HP and the gas furnace be operational at the same time in temps above 35*F if the furnace is set to none and the HP is set to lockout I sure would like to see where this is explained somewhere.

If the programmable fan option is set to on, where do you go to make changes to the fan speeds?

Regarding the fan control on the top right of the control, I have options of auto, low, med, and high. If I understand you correctly, any setting other than auto will continuously run the fan at that setting and will increase fan speed (if possible) should the control command it. I can't see that the programmable option has anything to do with this control.

No, both HP and furnace do not run at the same time.
If by chance your heat pump has a high demand that will use it's axillary function then it will turn off the HP and go to axillary heat which is your furnace, then your furnace will take over.

As a program fan speed
1 Flip down the door at the bottom of the control.
2 Press the SCHEDULE button to access the schedule screen.
3 Press the FAN button to access the Fan Speed programming
screen.
4 Press the LEFT or RIGHT button to select the days you wish to
program  ALLDAYS, WEEKDAYS, WEEKEND, or choose a
specific day (MON, TUES, WED, etc.).
5 Using the TIME (+\-) button, select your desired fan speed Â
LOW, MED, HIGH or AUTO.
6 Use the SCROLL button to highlight the next period, then
repeat steps 5 and 6 to select settings for DAY, EVENING and
SLEEP.
7 Press the FAN button to return to the standard scheduling
screen.
- OR -
8 Exit the scheduling mode by either closing the door or
pressing the SCHEDULE button.

Hybrid Heat Setup / Operation
Furnace Lockout  (in HYBRID HEAT SETUP menu) is the
outside temperature above which the furnace will not run except
for defrost (otherwise known as the aux heat lockout).
Heat Pump Lockout  (in HYBRID HEAT SETUP) is the
outside temperature below which the heat pump will not run
(otherwise known as the balance point).
These values can be set identical to each other. If they are not
identical, the system will stage up and down normally from heat
pump to furnace when the outside temperature is between these
settings. The User Interface will not allow the heat pump lockout
setting to be above the furnace lockout setting.
The factory default settings for both of these is NONE (no
lockouts). Even though a heat pump lockout temperature may be
set, the system will still use the furnace in defrost operation, and
may stage back down to heat pump when defrost is completed after
a 2 minute delay.
Hybrid Heat Defrost  (in HYBRID HEAT SETUP) When the
outdoor unit needs a defrost cycle, the furnace will run during
defrost regardless of lockout temperature, unless told not to in the
Hybrid Heat Setup screen. After defrost, the system may stage
down to heat pump after a 2 minute delay.

Thanks for the fan programming tips. I'll check that out when I have a spare moment.

I'm still struggling with the control logic regarding lockout of the furnace and HP. If, as you suggested, I set the furnace lockout to NO and leave the HP at Playing with the control and running the HP lockout temp up, I could see that the furnace lockout would automatically track the HP lockout (as you mentioned above) not allowing the HP lockout to be higher than the furnace lockout.

There are 3 scenarios I can think of for lockout settings, and I do not understand why one would be chosen over another:
1) furnace lockout - no (your suggested setting)
HP lockout at 35*F (using 35*F as an arbitrary value)

2) furnace lockout - >30*F (lockout greater than the HP lockout)
HP lockout 3) furnace lockout - >35*F (lockout equal to the HP lockout)
HP lockout - Perhaps the term staging up/down is what I don't understand. Keeping that in mind, how does the system operation differ between the examples above?

In a hybrid system like mine (with gas backup), does the HP have any other defrost capabilities (built in electric defrost?) than using the gas furnace for defrost?

Thanks for your tutoring!

You come home and you were out of town and set the temp to 50 degrees. The house is cold but outside is 36 degrees. Do you want aux heat to run to heat the house faster? That is usually why you don't lockout the furnace based on outside temp. Now you could wait the six hours the heat pump takes to heat the house or you can allow the furnace to run.

david_cary... another post from you that clears the mud from my eyes. You should rewrite the federal tax code. ;-)

Ok. Your explanation explains scenario #3... well, and also #2 for that matter... and scenario #1 as well.

Thank you.

One thing that still puzzles me is that I understand that the HP and the furnace won't run at the same time. If in the situation described above where the emergency heat comes on (gas furnace in my case), does the HP not run at all during the time the gas furnace is running when above the HP temp lockout?

If only the gas furnace is running above the 35*F HP lockout due to the demand to bring the interior temp up from 50*F to 70*F, at what point will the furnace shut down and the HP take over reverting back to normal programming where the HP maintains temp until the OAT drops below 35*F?

for a scenario #1 outside temp above 35F
The heat pump will run for 15 minutes, if it can not meet the demand in 15 minutes(default) it will then switch to the furnace.

Example #2 is efficency mode,
I would have this setting when the gas rate is high or I'm mad because I had my controller set for Example one and i had a big gas bill the prior month.
So example 2 is good for when the price for natural gas is high. Run the heat pump as much as you can before using gas.

3rd example is a compromise between 1 and 2.

So, when it come cold again, I would suggest setting your heatpump at a low lockout like #2 but raise it up if you want more instant heat when it's cold outside.

Remember you are a Tinker! and Bell would be proud! experiment with your own comfort level because the infinity controller does all the hard calculations for you, you just have to find your comfort level.

Thanks classicdave. Very helpful info.

The trick will be to remember it when the cold weather comes back!

classicdave,

I need to correct one of your very helpful posts. In the post where you include instructions on how to change the fan programming, you posted this:
"As a program fan speed
1 Flip down the door at the bottom of the control.
2 Press the SCHEDULE button to access the schedule screen.
3 Press the FAN button to access the Fan Speed programming
screen.
4 Press the LEFT or RIGHT button to select the days you wish to
program  ALLDAYS, WEEKDAYS, WEEKEND, or choose a
specific day (MON, TUES, WED, etc.).
5 Using the TIME (+\-) button, select your desired fan speed Â
LOW, MED, HIGH or AUTO.
6 Use the SCROLL button to highlight the next period, then
repeat steps 5 and 6 to select settings for DAY, EVENING and
SLEEP.
7 Press the FAN button to return to the standard scheduling
screen.
- OR -
8 Exit the scheduling mode by either closing the door or
pressing the SCHEDULE button."

In step 5, you said to change the fan setting use the Time button. However, the Time button merely changes the time. I found (at least on my version of the Infinity control) that you have to press the fan button to cycle through the available choices).

No biggee, but I thought it worth correcting.

Note: without the programming option being turned on in the advanced menu, the fan option will not come up on the schedule page.

Hello all. I cannot access the "fan" or "program" modes in the advanced setup dialog on my thermostat. What am I missing?

I may be able to help if you describe what you are trying to do.