GOODMAN GMH95 VS. TRANE XV90

[ECIndHVAC]

Hehe,

You know, I've always heard that only real reason why Trane has a better reputation than Goodman is because it's a lot easier for just anyone off the street to purchase a Goodman. And so, a lot of hacks install Goodman, and make mistakes that cause the unit to look bad, and so on. But Trane, on the other hand...you have to be a certified, licensed, uberprofessional, etc, to buy this stuff.

Well, one of these "uberprofessional" crews was located in Hartford City (until they went out of business in utter disgrace). Because they had this "difficult" customer who just didn't want to shell out all the extra cash for a Trane, they were forced to buy a lowly Ducane off my uncle (a nearby Ducane wholeseller).

They hooked it up, and (oh no!) bad compressor, DOA right out of the box. Can you believe that? (damn those lousy ducanes!) So they change the compressor, and guess what? Another failure! POS ducanes with their garbage COPELAND compressors! So they change out the compressor again, after complaining to my uncle for hours about how poorly engineered those nasty ducanes are. Another failure! This makes three in a row! So my uncle goes out on the job. Can you guess what the problem was?

Yep! One leg of the three phase power was shot!

Anyway, the moral of my story is this: The old urban legend that Trane only has a better rep than Goodman because they are more picky about who they allow to be their installers is probably false. I think Trane sells to any idiots just like any other manufacturer. At the time, Hartford City didn't have any Trane dealers, so they just hired that brain-dead crew at a whim.

[larobj63]

The IAQ can control the humidifier itself, and if you have an outdoor sensor, it can adjust the humidity as needed with the out doors temps.

In humidifier(heating) mode, the blower speed does not change, just in the a/c mode to control the blower speed to get a better humidity removal in the summer.

This is what the IAQ can do for your furnace.

-2 stage of heat as needed.
-Control your humidifier
-Slow down blower in the summer for humidity removal.


Having the t-stat control stage of heat is better than using the timer on the board.

Comfort-R slowly ramps up the blower, it don't know what the humidity is in the summer, and after 8 minutes, the blower is running full speed. IAQ will keep the blower at 80% speed unitll the humidity is below set point.


I have it on my system, and been pleased with it.

Just to be clear - the Trane TCONT800 series dehumidifies by essentially going below the temp set-point, but the IAQ slows down the blower to control humidity?

What is the part number for the IAQ?

Edit - just looked - the dehumidification one is TH8321U1006, right? That will work well with XV95 and XL15i, correct?

[mayguy]

Just to be clear - the Trane TCONT800 series dehumidifies by essentially going below the temp set-point, but the IAQ slows down the blower to control humidity?

Correct.

What is the part number for the IAQ?

YTH9421

Edit - just looked - the dehumidification one is TH8321U1006, right? That will work well with XV95 and XL15i, correct?

That is the same as the as the TCONT800. Honeywell makes these t-stats for Trane.

[larobj63]

Correct.


YTH9421


That is the same as the as the TCONT800. Honeywell makes these t-stats for Trane.

Thank you very much for the info. Cheers.

[RoBoTeq]

The GMH is a 2 stage furnace that can't be controlled by a 2 stage thermostat, it is a standard blower.

The XV95 is a great 2 stage 60%/100% that should be on a nice 2 stage stat like a Vision Pro IAQ. It has a variable speed blower for extra energy efficiency and comfort. The IAQ will also control said variable speed blower for dehumidification too.

The GMV would be more competition to the Trane is it can be on a 2 stage stat, have VS blower and dehumidification capability.

Agreed. There is no comparison between a standard blower and a variable speed blower. I'm still not convinced that both types of two stage units have their rightful places in the market. Personally, I would take a hybrid two stage furnace with a variable speed blower over a stat operated two stage with a variable speed blower, but I don't know if anyone even makes such an animal.

[mayguy]

Personally, I would take a hybrid two stage furnace with a variable speed blower over a stat operated two stage with a variable speed blower, but I don't know if anyone even makes such an animal.

Why would you want a furnace controlling the stages than the t-stat doing it?

[RoBoTeq]

Why would you want a furnace controlling the stages than the t-stat doing it?

The stat only knows what is occuring at the point of where the stat is located. An algorythmic furnace board (not a timed staging board) determines whole house consumption over continuous periods of time and regulates the furnace accordingly to calculated consumption. Calculated consumption equates to heat loss which equates directly to outside temperature.

If a door near a two stage thermostat is left open for ten minutes while the groceries are being brought in, the thermostat will attempt to heat that area to the desired set temperature which will overheat all other areas of the home by switching to high fire. If the same thing occurs with a single stage stat connected to an algorythmic board on the furnace, the furnace will continue to operate in low fire rather then blast out the rest of the house. Then the ten minutes of "heat loss" time calculated will be absorbed into the hours of regular usage calculations and not make much difference in the future operations of the furnace.

[mayguy]

Good point there, but will this set up cycle the furnace on and off?

I have a two stage Honeywell IAQ on my Trane XV90, and when we are -10, my furnace ran pretty steady in 1st stage, and cycle 2nd once in awhile. And when we had -20, the furnace ran steady for a couple of days, all the rooms where with in 1˚ from one another.

[RoBoTeq]

Good point there, but will this set up cycle the furnace on and off?

I have a two stage Honeywell IAQ on my Trane XV90, and when we are -10, my furnace ran pretty steady in 1st stage, and cycle 2nd once in awhile. And when we had -20, the furnace ran steady for a couple of days, all the rooms where with in 1˚ from one another.

I don't understand. The furnace cycles on and off when satisfied or calling for heat just like a two stage system operated by the stat does.

I'm assuming that your system is designed for -20f. If so, it should be running 24/7 on high fire when it is -20 out. This would mean that it should be going into high fire more then once in a while at -10f. If it is not operating this way, it is oversized.

[larobj63]

I'm assuming that your system is designed for -20f. If so, it should be running 24/7 on high fire when it is -20 out. This would mean that it should be going into high fire more then once in a while at -10f. If it is not operating this way, it is oversized.

That's a big surprise why? You have to round up when selecting - they don't make a perfect furnace size for every house! I know you know this - I'm just pointing it out. All but a few installations are oversized somewhat...

[mayguy]

I don't understand. The furnace cycles on and off when satisfied or calling for heat just like a two stage system operated by the stat does.

Another word, is 2nd stage forced to stay on till the the temp has met set point, or does it cycle back to 1st stage like a true 2- stage stat would?

I'm assuming that your system is designed for -20f. If so, it should be running 24/7 on high fire when it is -20 out. This would mean that it should be going into high fire more then once in a while at -10f. If it is not operating this way, it is oversized.

I don't recall what my design temp was, but it's some what oversized since 60k is the smallest they make in the XV90.

When we d0 get the -25˚, it did cycle 2nd stage pretty often, but overall it ran non-stop.


Like larobj63 pointed out, we can't get the dead on BTU rating.. I think the load calc came back at 54k?

[RoBoTeq]

That's a big surprise why? You have to round up when selecting - they don't make a perfect furnace size for every house! I know you know this - I'm just pointing it out. All but a few installations are oversized somewhat...

I disagree that you have to round up. You have to round out, either up or down. I prefer rounding down. I'd rather have a more efficient system all the time with rare extreme times where I might have to keep the doors shut more often or close the drapes. Let's face it, if your temps are five degress off either way during the few extreme temperature days, it's certainly not going to kill anyone.

[RoBoTeq]

Another word, is 2nd stage forced to stay on till the the temp has met set point, or does it cycle back to 1st stage like a true 2- stage stat would?



I don't recall what my design temp was, but it's some what oversized since 60k is the smallest they make in the XV90.

When we d0 get the -25˚, it did cycle 2nd stage pretty often, but overall it ran non-stop.


Like larobj63 pointed out, we can't get the dead on BTU rating.. I think the load calc came back at 54k?

Algorythmic calculated two stage systems are true two stage systems. They do stay in low fire when only low fire is needed unless there has been a longer run cycle in which they may go into high fire once in a while. These are not simply timers for stages where they run for five minutes on low and then on high until satisfied, that is not what the new hybrid algorythmic controls do.

A 60K furnace in a home with a 54K load would be perfect and would run 24/7 on high fire during times when the calculated load were present.