UT-3000 dampers, thermostats and other questions

[tnedator]

HI,

We will be installing four Amana ASCX18 Air Conditioners (not heat pumps) with ACVM96 modulating gas furnaces. They will be installed with UT-3000 control boards. Three of the units will have two zones, and one will have three zones. We will be using CTK03 thermostats in each of the nine zones.

I have some questions related to this setup.

1. In regards to the "reduces need for dampers." As I do not have heat pumps, which I saw mentioned in another thread as a reason that dampers could still be necessary, will it be necessary to install bypass dampers. Or, will the combination of modulating furnaces, UT3000 and CTK03 allow the elimination of bypass dampers?

2. Assuming the answer to number one is that dampers can be eliminated, if some of the zones have simple 24V thermostats, is it still possible to eliminate the bypass dampers, or will having some zones without a climate talk thermostat require putting bypass dampers in?

3. If I eliminate the CTK03 thermostat and go to home automation thermostats (like Lutron), which I believe will be seen as simple 24V thermostats to the UT3000, what do I lose in terms of functionality?

Thanks

[Erik W.]

1. If you set your dampers for leakage and create some open runs you can set up your system so it will not need a bypass damper.

2. If you use 24 volt stats the same thing applies as with communicating stats, you have to set your zone dampers for leakage and have some open runs to be able to eliminate the bypass damper.

3. If you purchase Lutron stats they will only be seen as 24 volt stats.The UT3000 allows the user to install Communicating Thermostats on all zones. Communicating thermostats can also be used in combination with 24v thermostats. You may also use regular Heat/Cool type thermostats or Heat Pump thermostats on all zones. This design simplifies the thermostat selection process and allows the installer to easily adapt the UT3000 to most any residential application. Regardless of the type of 24v thermostats used, the W2 Threshold feature or the OAS Set-Point will control the auxiliary system.
Once the W2 Threshold is crossed or the Outdoor Air Set-Point is reached, Auxiliary Heat will energize. Auxiliary demands from each thermostat are only used to determine the weight or percentage of demand from that zone, rather than immediately activating Auxiliary
operations.

Erik Wnoroski
EWC Controls, Inc.
385 State Route 33
Englishtown, NJ 07726
800-446-3110 ext 483

[tnedator]

Erik,

Thanks for the responses. Sorry, I think I confused things. I was trying to make it clear that I would NOT have heat pumps, but the way I worded it I think you understood that as me having heat pumps. So, I will have four 18 seer AC units with 96% modulating gas furnaces.

Regarding answer 1. Is there a down side to setting the dampers for leakage and open runs? Would doing bypass dampers be a more efficient route?

Regarding answer 3. First, as indicated above, no heat pumps. So, what I want to make sure is that I'm fully taking advantage of the modulating nature of the gas furnace to be as efficient as possible, and during AC operation, providing only the CFM needed for the particular zone.

I'm trying to understand what the benefit of the communicating thermostats are. I know they make the installation easier, but I'm more concerned with features after that. Will they allow the units to run more efficiently? Dehumidify better (lower fan speed when humidity is high)?

From what I've read in other posts, it seems like there are benefits to the communicating thermostats. So, if I use regular thermostats, will the AC unit still know to run the lowest fan setting possibly based on the temp and target? Or, is it simply a call for one or two stage cooling with a default fan speed?

Also, is there any thermostats other than the CTK03? Based on one thread in here, it sounds like that thermostat might have a problem playing nice with the UT-3000.

Thanks

[Erik W.]

Sir,

With the amount of questions you have pertaining to your system it is to much to cover in the forum and would be best handled over the phone. Please contact John Brown our chief engineer here at EWC Controls Inc. and he will assist you with all your questions. You can reach him at 800-446-3110 ext: 462

Erik Wnoroski
EWC Controls, Inc.
385 State Route 33
Englishtown, NJ 07726
800-446-3110 ext 483

[tnedator]

Will do, thanks. It's nice to have a company's support site that is this responsive.

[tnedator]

I talked to John a while back and he addressed all of my questions. I do have one follow up question, which I think I can get answered here without bugging John again.

After talking with John we are putting bypass dampers in, and I am using communicating thermostats on 9 of my 10 zones.

On my last zone (two zones on a 3 ton, two stage unit, modulating furnace with variable speed blower), my current plan is to use a Crestron 24v thermostat. The Crestron installer just told me that the Crestron won't work with a variable speed fan. However, I know the UT3000 docs say any 24v thermostat.

The equipment will be Amana Air conditioner with modulating furnace (I will not have a heat pump, just strait AC/Gas furnace).

Will the UTC/Amana still ramp up and down the variable speed fan as needed or will it always blow on high whenever the 24v thermostat makes a call?

Can you just briefly run through any issues or features I won't get if on that unit I have one communicating thermostat and one 24v thermostat?

Thanks

[tnedator]

I did just make an edit to my last post indicating that it is a variable speed modulating furnace in case that impacts your answer.

[Erik W.]

The Crestron thermostat is compatible with the variable speed modulating furnace because the UT 3000 is operating the blower not the thermostat. As for what features you will not get with the 24 volt thermostat it is you will not have access from that thermostat to the advanced comfort net menu, but you can access it from any of your other communicating thermostats. You will also not have proportional control from a 24 volt thermostat like you would get from a communicating thermostat.

Erik Wnoroski
EWC Controls, Inc.
385 State Route 33
Englishtown, NJ 07726
800-446-3110 ext 483

[tnedator]

The Crestron thermostat is compatible with the variable speed modulating furnace because the UT 3000 is operating the blower not the thermostat. As for what features you will not get with the 24 volt thermostat it is you will not have access from that thermostat to the advanced comfort net menu, but you can access it from any of your other communicating thermostats. You will also not have proportional control from a 24 volt thermostat like you would get from a communicating thermostat.

Erik Wnoroski
EWC Controls, Inc.
385 State Route 33
Englishtown, NJ 07726
800-446-3110 ext 483

Ok, so if I have this right, from what I've read on here and in the manual. We would need to hard code the zone weighting for the room with the Crestron remote (defaults to 50%, can be set in 25% increments) and it will be fixed at that, rather than taking into account current temp, target temp, etc. Correct?

One last question, based on what I read in another thread. We need to have the Crestron remote put the fan in "on" mode at times without a call to cooling/heating, to vent out equipment heat when it's running. Based on another thread in here, it seems that if the fan is set to auto on the communicating thermostat, that as it "learns" it will ignore the call for fan to "on" from the 24v stat. Is that correct? If so, then I think my only two options are to keep the fan on the communicating set to on all the time, and run the blower 24/7, or on this unit, use two 24v thermostats and not have a communicating stat. Do I have that right, and what is your suggestion based on this need?

[Erik W.]

I have discussed this issue with our Chief Engineer John Brown and we are having some difficultly deciphering what you are trying to achieve. Please contact Mr. Brown at 800-446-3110 extension 462 to discuss in further detail.

Erik Wnoroski
EWC Controls, Inc.
385 State Route 33
Englishtown, NJ 07726
800-446-3110 ext 483