gb142-24 thermostat options

cumminsman

Hello everyone,

gb142-24 in floor radiant heat all one zone in garage floor(32x40) 10 ft cealings not using dhw..

Have am10 outdoor reset controller, boiler is hooked up running fine in manual mode but looking on what i can use as a thermostat for my garage.. my ? is do i need to use a rc 35 controller or can i use a convential digital thermostat if so i could use some info on hooking it up... Not looking for anything fancy just looking to control the garage temp when in use and can turn down on days im away on the job... Thanks for any info or pointers.... Kyle

Zman

T-stat

I like this one. http://www.pexsupply.com/Wirsbo-Uponor-A3030101-Wirsbo-Radiant-Thermostat-WT-1-Heat-Only-Two-wire-2063000-p



It works with a 2 wire system and has some basic radiant controls built in.

You can also lock out the minimum and maximum setpoints.

Any 24 volt t-stat will do the job.

Carl

Ironman

X2

I second what Carl said and would add one other thing:

Get the outdoor reset curve tweaked to match your floor and heat loss and the thermostat will become almost unnecessary - just use it like a high limit.



I wouldn't be turning the heat on and off or setting the stat back and up. The radiant floor is high mass, which means it will take along time to heat up and a long time to cool down. Using setback is counter productive to the logic of the GB142 and the floor won't respond well to it.

cumminsman

connecting tstat

Thanks for the help your right that is my need to control high limit of heat is my only need for the tstat, i will probably go ahead and get that tstat is that my reason why i cant get it to run in automatic by just switching the unit on bc nothing is controlling the output temp desired?? Another ? is i started to adjust my limits today on the am10 but it is not letting me adjust the supply temp it is stuck at 32 but in the directions it shows it can be adjusted to set desired supply temp... Maybe i got something hooked up wrong... Also does the thermostat hook into the am10 or into the wa pins of the 24v supply board?? Sorry for all the questions just seems this is all i need to figure out to finish my unit and its becoming a pain....

Zman

WA

Yes the t-stat goes to the "WA" terminals. If you want it to run "always on" and set the outdoor reset and WWSD to control it, you can jumper WA. You can also jumper it while you are waiting for the t-stat

Carl

Ironman

"WA" terminals

If you connect to the WA terminals the boiler will heat to the setting of the limit on the dail - 194* if set to "auto". The AM10 and the reset curve are over-ridden by WA.



To use reset, the thermostat must connect to the AM10. Or, you can jumper the thermostat terminals on the AM10 to allow it to control the water temp by reset. WWSD and reset are both done in the AM10, not the boiler.

Zman

I stand...

Corrected!

Thanks Bob for the correct answer.

Carl

Ironman

Boost

Carl,

As I'm sure you know, there is no boost feature on the GB142 boiler: the German engineers think it's unnecessary and counter-productive to reset on a mod/con and I agree.



However, when you get a customer that insists on using setback (like the one in the long thread), you can use a two stage stat and connect the second stage to "WA" and accomplish "boost" that way.



I'm heading out to do this on a Lochinvar WHN that we installed this week. The customer uses the house on the weekends only and wants to keep it setback during the week. Understandable. The boost feature on the WHN can only be delayed for up to 50 minutes when enabled. I've got the reset curve tweaked so well that the boiler will modulate down and run for hours - unless boost is enabled. Then it kicks in at 50 minutes. I'm gonna disable it and install a Honeywell th8320 WiFi stat and connect the second stage to the unused heating zone on the boilers control and set that to go to 160 - 180*. That way they can have boost and the house will be up to temp for the weekend. And, the rest of the time, the reset curve will control the water temp.

cumminsman

Update on tstat and boiler settings

Hello everyone, made it back in from a few weeks of work and my tstat showed up planning on hooking it up tomorrow or sometime this week. Went with Honeywell focus pro 5000...I'm planning on hooking that into the outdoor reset as suggested but looking for some information on setting my high and lows/heating curve on reset, also is there a reason I can't adjust my supply temp on the am10/ will this become possible when tstat is hooked up. Thanks Kyle

Ironman

Reset curve

We need to know the heat loss of the structure, the design temp, how much and what size tubing is in the floor, etc. to properly determine the settings on the AM10.