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Phil Thien
06-08-2014, 10:08 PM
Hi.

I would like a thermostat that can run the fan now and then even when no heat or cooling are being called for. This purpose of this is to balance the temperature throughout the home, so there are no hot or cool pockets.

I know I can just leave the fan "on," but the ones with the circulation features apparently work as well and save some money because you run the blower less and the filters last longer, too.

Any recommendations?

I've looked at some of the wifi units but I really don't know if I want that. I'd just as soon have a thermostat with (if possible) a three-position fan switch: On, Auto, Circulate.

Brian W Smith
06-09-2014, 6:28 AM
Largely depends on how much "effort" you want to put in.So many times we "talk the talk"(and am not referring to you).........and then,the OP or customer just goes,"oh thats more trouble than we wanted".Or "money",or whatever.

Having said that,off the top of my head,you're looking at three ways to accomplish the task....all,with their own burdens of effort.

>Passive system...."look honey,it's like magic"

>Integrated electronics.....find a "controls" expert

>split system.....add-on unit that can stand alone.Simple timers that don't really need to "talk" to each other.

Charles Wiggins
06-09-2014, 8:35 AM
Greenhouse thermostats maybe? http://www.littlegreenhouse.com/accessory/controls.shtml

Phil Thien
06-09-2014, 8:50 AM
Largely depends on how much "effort" you want to put in.So many times we "talk the talk"(and am not referring to you).........and then,the OP or customer just goes,"oh thats more trouble than we wanted".Or "money",or whatever.

Having said that,off the top of my head,you're looking at three ways to accomplish the task....all,with their own burdens of effort.

>Passive system...."look honey,it's like magic"

>Integrated electronics.....find a "controls" expert

>split system.....add-on unit that can stand alone.Simple timers that don't really need to "talk" to each other.

I want to put this much effort in: Remove existing thermostat, install new thermostat, program new thermostat.

Pat Barry
06-09-2014, 9:51 AM
We had a new furnace and AC installed last fall. They put in a Honeywell 7 day programmable thermostat. I'm fairly certain you can program the fan to turn on and off as well as set temperature points for heat and cool. I'll verify when I get home.

Jim Becker
06-09-2014, 9:59 AM
The type of system you have is an important part of the equation...ideally, your HVAC system should have at least a two-speed fan, if not a fully variable fan. That's what makes what you want to do economical and effective. With that setup, when you leave your thermostat at "fan on" (which we do here and have for many years), the fan only runs slowly to circulate air for comfort and to help filter out some of the suspended "stuff".

Phil Thien
06-09-2014, 10:08 AM
We had a new furnace and AC installed last fall. They put in a Honeywell 7 day programmable thermostat. I'm fairly certain you can program the fan to turn on and off as well as set temperature points for heat and cool. I'll verify when I get home.

Thanks Pat. The Honeywell units I've found so far don't have the fan circulation feature until you hit the sorta expensive touchscreen versions. But I'm just reading manuals online and some of them may have been updated so it is hard to know for sure. I should probably call Honeywell.

Matt Meiser
06-09-2014, 10:34 AM
Ours has it but it is one of those expensive touchscreen Honeywell units--a Vision Pro 8000. Its a nice thermostat--real humidity control, outdoor temp, nice hold features where we can set it back for x days of vacation (or until 2:00 after a showing is complete.) No idea what it cost as it was a requirement for our heat pump system and the cost was rolled into that.

Lee Schierer
06-09-2014, 1:27 PM
Our heat pump has a variable speed fan. We can run the fan only on a very low speed and it keeps the house nicely balanced from sun side to shade side. We run the fan continuously when we are heating or cooling. When the unit actually heats or cools, the fan increases in speed for until the set temp is reached.

Tom Stenzel
06-09-2014, 3:52 PM
I can't "recommend" this as I don't have any experience with them, the Aprilaire 8463 might do what you want.

From their Minister of Propaganda:
Circulate fan mode (if the fan has been off for 20 minutes the fan will be activated for a 10 minute cycle. Use this mode for a balance of energy savings and air circulation/cleaning).

So it looks like it runs 10 minutes of every 30? I think that's they mean.

See
http://www.prothermostats.com/product.php?product=174866

PDF's are available from the site. No endorsement of prothermostats, never heard of them before I googled for your thermostat. Nor have I ever used an Aprilaire either.

-Tom

Phil Thien
06-09-2014, 4:02 PM
I found a Robertshaw unit that runs the fan ten minutes for every thirty. It should be compatible as it only requires four wires (single stage systems).

I think running the fan for twenty minutes of every hour should be satisfactory for balancing the temps in the various rooms of the house. Right now I run the fan 24/7, which is okay but it is probably costing about $30 - $35/month in electricity. So this should cut that to $10 to $12/month, saving up to $250/year. Not bad if it works as well as the reviews indicate.

Kev Williams
06-09-2014, 4:28 PM
I can't keep all the rooms the same temperature with the furnace or AC running, I doubt running the furnace blower by itself would ever even out the temps!

Phil Thien
06-09-2014, 5:32 PM
I can't keep all the rooms the same temperature with the furnace or AC running, I doubt running the furnace blower by itself would ever even out the temps!

The more the blower runs, the more it blends the air throughout your house, reducing temperature differences. On most moderately cold or moderately warm days, the furnace and AC don't have to run so much, and if the blower is only on when heat or cooling are called for, the blower doesn't have enough time to mix the air in different rooms to equalize the temps.

So running the blower by itself is PRECISELY the solution to making all your rooms the same temperature.

I've been doing so since moving into my house. The 2nd floor was quite warm compared to the first, as heat likes to climb right up the stairs and stay there. So I was advised to leave the blower on and that was indeed the fix. The reality is, though, that I don't think I need to leave the blower running 24/7. Twenty minutes out of every hour, I've heard, is sufficient. And it should allow me to save about $250/year.

I hate to think that I've lived in the house now for nearly 20 years, so if this new thermostat works, I could have saved nearly $5000 in electricity.

Pat Barry
06-09-2014, 8:46 PM
We had a new furnace and AC installed last fall. They put in a Honeywell 7 day programmable thermostat. I'm fairly certain you can program the fan to turn on and off as well as set temperature points for heat and cool. I'll verify when I get home.
Nope - sorry - only can set temperature vs time of day, not fan

Dick Phillip
06-09-2014, 9:03 PM
The Nest thermostat will do what you are looking for.

Phil Thien
06-09-2014, 10:20 PM
The Nest thermostat will do what you are looking for.

I looked into them but the reviews weren't overwhelmingly positive enough to warrant the price. Plus I do IT for a living and the last thing I want is to have to support a Nest for my family or my daughter's house.

The Robertshaw units I found were $45 shipped for a seven-day programmable with a circulate feature.