New furnace - two stage and variable speed.

[RJ]

I just had a two stage variable speed furnace installed. I didn't seem to notice any change from my old furnace so I investigated the manual. It looks as though there should be 6 or 7 wires from the thermostat to the furnace for the two stage thing to work. I have five (I think). How do I know that the thermostat is two stage? Also this furnace is advertised as having something call continuous fan and I am (according to the doc) supposed to be able to adjust the fan speed by turning the fan off then on from the thermostat. The speed never changes. I am wondering if that has anything to do with the wiring too. I know that the furnace can handle not having a two stage thermostat. But I would think that since I have it it should work right. Does this sound correct? Could someone please advise me as to what to do next? Are there any tests that I can perform to confirm what I think is happening? Should I just call for service and have it fixed? TIA. By the way the furnace is a carrier 58cva090 and the therm a honeywell vision pro 8000

[HeatMan]

The Vision Pro 8000 is a 3 stage heat, 2 stage cool thermostat. For best performance, you'd need 6 wires, but that includes a common for the tstat itself. You can get 2 stage operation out of a 5 wire system and the Vision Pro.

[No]

You do not need 2 stage thermostat for such furnace two work - they are smart enough themself to dicide if work in lower or higher capacity. Manuall has description on how furnace behaves with 2 stage thermostat and with 1 stage thermostat. For continuos fan - I had same problem. In my case just turning off and then right away on fan from thermostat did not work. I have to turn fan off, wait about 2 sec (not more than 3, but not less than 1 !!!!!) and then I saw that fan speed really changed.

Could you please tell me when your furnace is working - is there watter dripping out of your outside vent pipe? For some reason in my installation water is dripping and I am not sure if this is normal.

[HeatMan]

You are correct to say that the OP doesn't need a 2 stage tstat for proper operation of his 2 stage furnace, but even with a built in time delay, he's not getting the full value out of his furnace.

[HvacTech2]

Hi RJ, hope you are having a nice day

On 20-Oct-04 At About 20:31:16, RJ wrote to All Subject: New furnace - two stage and variable speed.

R> From: [e-mail] (RJ)

R> I just had a two stage variable speed furnace installed.

If you just had it put in you should be able to call the installer and have him answer your questions and/or correct any problems at no charge.

-=> HvacTech2

[RJ]

Thanks for all of the advice. So the guy finaly came out and had no clue. They won't rewire for the two stage because the two stage function is working and they couldn't figure out the fan situation. Ugh. I email'd Honeywell and the tech said that I could not change the fan speed at the thermostat which I think is a bunch of crap because the furnace manual says that just by shutting off then back you should be able to change the speeds. The problem with this thermos is that it has a touch screen. To go from ON to OFF (AUTO) requires a number of touches and I don't think that I am meeting the requirements of between one to three seconds between on and off. Talk about frustrating!! Any suggestions?

[m Ransley]

You dont say what furnace you have but I know of only one you can change the fan speed at the thermostat, Carrier Infinity with only their Stat. You talk about many different things I suggest you call the furnace manufacturer and get the true story.

[No]

Carrier Infitiny you can change continuous fan speed from any thermostat or by changing switches on furnace board. On any thermostat: when fan is in ON position, turn it off for about 1-3 seconds. I tested that, and it does work.Every switch off/on increases fan speed to next level, till it goes back to the first level.

On furnace board - it is really easy to find that switch, you will have to just unscrew 2 screws before you will reach switch. Documentation says what position switch represent what speed.

Regards,

[m Ransley]

That isnt what my instaler or Carrier said, they said I need the Carrier Tstat, and only one of Carriers many stats would work, but maybe it is a newer model.