Wiring summer switch

I have a G9T06010UPB13A high efficiency furnace. I would like to wire it for summer switch (I have an options on my thermostat). Problem is there is only 2 wires right now that go to my thermostat. Any idea how I can wire the furnace to use that setting? I can run new wire with ease between furnace and thermostat
Thanks for any help.

Not sure what you mean by a summer switch?! If you mean you want to force the fan on, if the furnace supports that, you'd need one more wire. While you are doing it, you might as well run a 5-wire cable, then, should you change anything, you'd likely have enough to support it...actually some can use a sixth wire, but most only use 5. Then, you'd be able to add a/c and support multiple stages, if it supports that, as well.

Thanks for the response. Yes, I meant I want to force the fan on, since my basement is much cooler than my upstairs. This would equalize temp through the house and in turn cool the top floor a bit since i don't have ac.
I did find another (red) wire that was hiding in my wall behind the thermostat. I can easily attach it to my thermostat. Unfortunately the other end is not attached to the furnace. I'm not sure where should I attach it to, to make the fan go. Any help would be appreciated.

Somewhere inside the furnace, possibly on the back of one of the covers, you might find the wiring diagram for the furnace. That will help.

I'll check tonight. I'm sure there is something there just not sure if it will be marked as (connect fan wire here) lol
I'm fairly handy when it comes to anything, but never messed with furnace before and I don’t want to destroy it by connecting it to the wrong place. (i'm clueless about furnaces) Any generic place it should be in? Like would it be on the motor, or maybe some switch or something. I’m sure they are all different but I’d think they would have similar location for wiring.
Thanks in advance

If it has only two wires then most likely the Blower is controlled using a Temperature operated switch in the heat exchanger.

You could use a relay in parallel with that blower switch, and control it with a air conditioner thermostat.

Assuming your thermostat has a fan/auto switch, and your furnace has a terminal to control it, generically, it is usually the G or green terminal. Hook that wire up to the G terminal on the thermostat and the other end to the G terminal on the furnace, and it should work. Before you do anything, though, verify by looking at the wiring diagram or call someone familiar with that specific furnace. If you have the owner's manual and/or installation guide, it should show this - figuring it out from the wiring diagram inside the cover can be done, but each company uses their own symbols, and it can be hard to read if you've not worked with them before. Basically, you're applying 28vac to the furnace so it can energize a relay (or other electronic control) to turn the fan on.

Attachment 16609Attachment 16610

I can't see "G" terminal in the furnace. Any idea by looking at the pics?

I have a w-r model 50a50-241 control for my furnace. Where would i attach a wire for low speed or high speed? Would it be on cool, heat, park , or park?
Thanks

Ok I found the G terminal.
I attached green cable to G terminal in the furnace, and the other end to G terminal on the thermostat
Here is the pic. Still nothing though. My thermostat says that it is working on cool, but the fan does not turn on in the furnace. I tried on and auto option.
Any insight?

What is the make and model of your thermostat ?

Does your T-stat have a fan switch...labeled ON-OFF-AUTO ??

I think that the red wire should be connected to R. Why the black was used instead of red seems incorrect.

The black may be in the wrong place on the thermostat. That would depend where it connects to the thermostat, and the type of thermostat.

The thermostat may need a Return connected to C. (another wire if it requires power)

May be time to get the voltmeter out, and look at the thermostat manual.

Sounds like it may have On/Auto Fan switch. If not No Go.

With nothing connected to Y, Then the thermostat should not have a Cool mode.

Is this unit connected to a Air Conditioner also ?

Thanks for all replies.

The model of thermostat is noma 303M
here is the pic for the wiring:
I had only 2 wires attached (as in 2 wire diagram) black into RH and white into W
I added green wire to G both in the furnace and in the thermostat.

I have no AC
I tried to run the fan on heat (it works with the heat but not without)
I tried to run on cool (auto and on option) Thermostat kicks in and it shows that it is cooling, but fan in the furnace does not kick in
Would I need another wire for Y to make it work?

Thanks

Seems that you could run it on heat and put the temp very low. (So heat is not called for)

Would that make the fan run ?

I don't think a connection to Y will help.

Just connect it for the number of wires you are using.

3 should work.

I tried that with auto setting, and that didn't work. It only moved the fan when i cranked the heat up (higher than room temp) I never tried with ON all the time (at least that i can remember as i was switching it back and forth). I'll give that a try, though it would be nice to have it to kick in in auto mode, but i'll take what i can get.
Will let you know tonight

thanks