HVAC type question

[Richard]

A 3-way switch can have two different locations to control a single light.

Can you do same with your thermostat?

Here's my situation...

House has two units. Smaller unit for bedroom/upstairs. Larger unit for main floor and walk out basement (finished).

Right now, I have a propane/ventless fireplace on the main floor. We never turn it up past "idle" since it will keep this floor nicely comfy, OR, even take this floor up to maybe 80 degrees after a while.

My thermostat is on this floor, for this HVAC system. As this floor warms up, the furnace (heat pump) stays idle since my thermostat is set maybe 65/70 degrees. What happens is my basement gets colder and this floor gets warmer so what do I do?

I simply turn the fan on which helps mix the colder air downstairs with the warmer air up here. works like a charm.

I'm now working on finishing the main room in the basement. Wife wants to add another fireplace down there (also ventless)

What might happen now is, the basement might get warm BUT, the upstairs might be cooler and therefore kick the furnace on.

What I'd like is a way to turn just the blower on while I'm down in the basement (this is where the TV and HT system are going to go, so it's a no-brainer that I'll be spending more time down here when it's done)

So... given that I have (what I think is) a 4 or 5 wire, thermostat on my main floor, can I somehow wire in another one that will give me simple on/off control of my blower while I'm downstairs so I don't have to keep running upstairs?

I don't think I'd have the ability to easily run new wires to the upstairs unit, but I'd be MORE than willing to flip out the upstairs unit and add anything I need in the basement to help make this possible.

Thoughts?

Actually...now that I think about it, I probably DO have access to the area under the floor (in the basement) that the upstairs wall is sitting on. I'd just hate to miss that floor plate with a drill...the wife would kill me It would be much better to utilize existing wires if possible.

hmm.. RF??

 

[Richard]

I should clarify... I don't necessarily want a second thermostat to put downstairs, just some way to turn the blower on.

 

[eepete]

Google "thermostat color code". Look at the diagram for a thermostat. The green wire runs the fan. You can duplicate your fan auto/on with a switch downstairs. You will be connecting the green to the red (24V AC) with a switch. Note how the fan, when on, is independent from all other things. The Red wire out of the heat pump should already have a fuse before it, typically a 5 amp fuse. So use the right gauge wire for that, I'd use an 18 gauge.

You can get at these wires by breaking into the thermostat wire, or (cleaner) just run two wires back to the heat pump and connect them there.

Pete

 

[Richard]

Ok, this is slick!

I've not looked at any of the wires so most of what you say is foreign to me.

Fortunately, my air handler is about three feet from where I'm thinking I want to put a switch so it will be VERY easy to get to!!

Would I be able to put a simple light switch there (like a 120volt normal wall switch) or should I use something different since the needs / voltage are different.

Mind you, I don't MIND using the larger switch since I already have a handful of those. Probably be easer than finding something smaller.

Would I need a 3 way switch?

I probably won't get to poking my head around until this weekend but this is the answer I was hoping to get!!

 

[SPIKER]

you should be able to tie in a 2nd thermostat down stairs directly at the heat pump control, which I assume is downstairs? BUT all you would need to do is tie in the "Blower ON" when temp is turned on. (if you dont want the blower running turn basement thermostat to 50) if you want it running turn it to 70 or 75. (some degrees above above basement temp.)

You will need to tie in the two wires that feed the blower on, and this can be done at the 1st floor thermostat or the main control junction point, (this maybe out side on a heat pump or your instillation.) where ever the main heat source is at.mark

 

[hr3]

Rich.. Does your heat pump have a fan switch on it now,, if so where is it.. It's very easy to do what you want with a 3 way switch,, In on position the switch will turn the fan on,, and in the other position it will put it back in auto..

 

[Richard]

you should be able to tie in a 2nd thermostat down stairs directly at the heat pump control, which I assume is downstairs? BUT all you would need to do is tie in the "Blower ON" when temp is turned on. (if you dont want the blower running turn basement thermostat to 50) if you want it running turn it to 70 or 75. (some degrees above above basement temp.)

You will need to tie in the two wires that feed the blower on, and this can be done at the 1st floor thermostat or the main control junction point, (this maybe out side on a heat pump or your instillation.) where ever the main heat source is at.mark

Ok... let me rephrase the picture a bit just to see if I'm getting this.

(I've been pulling wires so my electrician brother in law won't have to, so I've been in the "be careful about your wires" mode)

If I use an octopus as an example...an octopus with only two tentacles...would that be a bipus? lol

anyways... one of the tentacles is made of say, 5 wires (or how ever many go to the thermostat). These currently go up the wall to my upstairs thermostat and everything is currently controlled from there.

I can attach ANOTHER thermostat in my basement... take 5 more wires (or however many might go to the thermostat) and wire these to the same lugs the upstairs thermostat is tied to?

I then presume that I have the chance of these thermostats 'competing' with each other, until I figure out how I want them adjusted. I realize they will NOT give me "upstairs and downstairs" (independent) heating & cooling but rather, two locations from which to control things, within the constraints of them sharing the same air handler?

I'll admit that I already sort of like the idea of the thermostat in the basement being able to turn the blower on (presuming the upstairs thermostat is currently not tripping it on)

This would allow the idea of SOME form of controlling how hot it gets downstairs. I could put the thermostat on say, 75 and if it got over 75 it would automatically turn the blower on to mix the air with the air upstairs.

am I getting that?

Do I have to use special thermostat wire?

I currently have about 600 feet of Cat 6 wire (4 twisted pair) at my disposal. Other than the wire count, I'd speculate I could perhaps use that?

I figured this could be done, I didn't know it might be as easy as I'm starting to believe.

 

[Richard]

Rich.. Does your heat pump have a fan switch on it now,, if so where is it.. It's very easy to do what you want with a 3 way switch,, In on position the switch will turn the fan on,, and in the other position it will put it back in auto..

The only switch I currently have is the "fan on" switch located on the upstairs thermostat

I'm hoping on having the access to turn the blower on while downstairs. Truth be told... sometimes when I have our current fireplace on and turn the blower "on" (verses auto), I will sometimes forget about it and leave it on for a couple days before flipping back to Auto.

 

[tallyho8]

Would I be able to put a simple light switch there (like a 120volt normal wall switch) or should I use something different since the needs / voltage are different.
Mind you, I don't MIND using the larger switch since I already have a handful of those. Probably be easer than finding something smaller.

Yes Richard, you can just use a regular 49 cent light switch and run wires from the 2 terminals on it to your red and green wires on your thermostat to be able to turn your blower on and off from downstairs as you wish. (very simple)

You will have to turn this switch off in order for your thermostat upstairs to be able to turn the blower off.

 

[eepete]

The red and green wire at the thermostat are the same as the red and green in the heat pump where the thermostat wire connects, so you can connect at either place, which ever is easier. You can use a standard light switch. If you put it in a dual box with something that has AC in it, be sure to put the orange divider between the two sections.

Don't use the CAT6. That's 24 gauge wire and it has a 1 amp max current, and your heat pump is (probably) fused at 5 amps. Use 18 gauge or a piece of thermostat wire- then you can use the correct colors.

When you have your downstairs new fan switch on, the fan is always on no matter what the thermostat upstairs wants. So yes, you can leave it on too long by mistake too as tallyho8 has mentioned.

This might be what SPIKER was referring to: With your added description of what you want, there is another way you can go. You can place a new simple thermostat downstairs. Use the white wire connection point on that new thermostat and connect it to the fan (green wire on your heat pump). Then you set the temperature on that downstairs thermostat and when that room is cooler than the set point the fan runs. Note you must also connect the red wire to the red connection on that new downstairs thermostat. When your downstairs room is warm enough, the fan turns off. If you turn the new downstairs thermostat off, it's out of the picture and can't run the fan.
I did this for my Dad years ago when he had a wood stove going in part of the house, and wanted to spread the heat around to another room. Works great.

I would not parallel two thermostats. I can explain why if someone wants to, but I'd stick with the "something that works is better than something cooler that's flakey" rule of life.
They make dampers and zone controllers for true two rooms at independent settings on one heat pump situations. If the simple fan hack doesn't work, then talk to an HVAC guy about putting that in.

Pete