Thermostat Options for EWC-ST Series Control Panels

[Erik W.]

The White Rodgers 1F95-1271 or IF95-1277 Touch Screen Programmable Thermostats are able to be programmed for 7 day and Have separate o and b terminals

Erik

[DaveLCT]

Eric,

I have the EWC-ST-2D running a Trane TWE Hyrdo hot water air handler with a Burnham PV75WT oil fired boiler and a Bock hot water storage tank. My cooling is a conventional Trane A/C.

I have been considering adding a Nest thermostat to Zone 1. My research on the EWC website indicates that Zone 1 requires a dedicated “O” and “B” connection at the thermostat; and therefore this would not work as currently configured. My further research on the website suggests that one solution seems to be adding a MCS-DXB and running the O and B plus R1 from the Zone 1 TSAT Block to the MCS-DBX; leaving W Y R1 and G going to the Nest thermostat.

Is this correct, or is the solution an upgrade to the NCM-300 board?

David

[Erik W.]

David,

I would recommend just using the switch it is not necessary to upgrade the board. All the factory wires will be included in the switch you will need to wire the switch to the R1, O, B and G terminals. Your nest thermostat will then only need three wires R, Y and W if you are using battery power and a forth common wire would need to be added on the C terminal if you want to power your stats with 24 v

Erik

[DaveLCT]

Erik,

Thank you for your response and I am sorry about spelling your name wrong last time.

So if I want constant 24v power to the Nest, can I grab the common off the Zone 1 TSTAT “C” terminal block? Also, I understand that the Nest likes to control the air handler fan for a short period after the A/C compressor shuts off; this being the case, can I give the Nest the “G” wire or is it necessary to have the “G” wire go to the MCS-DXB?

Many thanks for your help.

David

[Erik W.]

David,

Yes you use the C terminal on the zone 1 thermostat terminal block to run the nest with 24 v power from the board. You can wire the G either to the switch or straight to the G terminal whichever is easier for you.

Erik

[emwilli]

I have an EWC-ST-2E controlling two zones, upstairs and downstairs, with separate thermostats. i would like to buy and install the Honeywell Prestige 2.0 thermostat. My question is, can this panel work with this thermostat and can this one thermostat be used to control both zones, instead of using two thermostats Thanks.

[Erik W.]

Unfortunately that thermostat is not compatible with our ST Panel.

Erik Wnoroski
EWC Controls

[emwilli]

Thanks Erik for the quick response. Is it possible to control two different zones with a single thermostat? I have a sinle heating and cooling unit with two motorized dampers for two zones.

Thanks

[Erik W.]

Unfortunately no each zone is controlled by a separate thermostat, if you were to control them by the same thermostat that would basically unzone your home.

Erik Wnoroski
EWC Controls

[hancox]

So, finally getting around to installing my thermostat replacements (of course, when it turns colder...)

My upstairs Robert Shaw thermo has:
White --> W
Red --> R
Black --> B

...seems like an exact match to the TH4110D1007, so hopefully cake.

The downstairs Honeywell has:
White --> 4
Red --> 5
Black --> 6

...in the same general pattern. Is this just as easy? (ie R to R, W to W, B to B on the TH4110D1007?)

I'm keeping the MCS-DXB as-is, as it gives me a nice reason to replace my filter 2x a year.

So, I ended up hooking my 2 TH4110D1007's this way. No issues at all during heating season. (MCS-DXB and thermo switches turned to heat).

Now, I just tried a cooling test (on only the downstairs for now). MCS-DXB set to cool. The AC did not turn on with the TH4110D1007's set to cool. They did turn on when set to heat, and below temp (which sort of makes sense, given the former setup with dial thermometers). Only worry is - once the thermostat went back to "heat on" mode, the AC didn't shut off. I admittedly didn't try it for too long, so I might have just been impatient. Any chance I did something wrong here?