urhstry
ArboristSite Operative
I just replaced my baystat thermostat with a digital unit and have a small wiring issue. If anyone can help I wood (arboristsite content) appreciate it. PM me.:help:
Any Trane HVAC mechanics out there?
- Thread starter urhstry
- Start date
Help Support Arborist Forum:
mtfallsmikey
Addicted to ArboristSite
The Trane stuff I maintain is commercial but.....did you compare your existing low voltage diagram vs. the new t-stat? Aftermarket t-stats are a PITA, especially when grafting to heat pumps. Is that what you have? Also, pay attention to how the DIP switches need to be set up.:monkey:
urhstry
ArboristSite Operative
Well, this aftermarket thermostat is the Trane replacement. No DIP switches to set. Only six wires to move around. Only one wire is screwing this up I think. Thanks.
AOD
Addicted to ArboristSite
Do you have two seperate power sources feeding this T-stat, such as a transformer from a heat pump and one for a furnace? IF this is the case these need to be kept seperate, most stats have an Rh terminal for heating power and an Rc terminal for cooling power. These are usually jumpered together in the typical case of one control txfmr feeding power to the entire HVAC system, but a heat pump may be different.
FWIW I hate air-air heat pumps! You couldnt pay me enough to have one anywhere outside of the Deep south.
FWIW I hate air-air heat pumps! You couldnt pay me enough to have one anywhere outside of the Deep south.
urhstry
ArboristSite Operative
This is only an A/C unit with a water/air exchanger in the mix. Hot water from teh boiler comes into the HX and the fan running on the A/C unit blows the air intothe registers. How's that for a technical explanation! 
Anyway, i think I may have found the problem. I only had six wires to move around but forgot about the copper traces running all over the baystat. Once I traced them and added jumpers, I think things evened out. Thanks for everyone's help.
Anyway, i think I may have found the problem. I only had six wires to move around but forgot about the copper traces running all over the baystat. Once I traced them and added jumpers, I think things evened out. Thanks for everyone's help.
mtfallsmikey
Addicted to ArboristSite
Sorry...i should have mentioned jumpers as well as DIP switches! Depending on the make of the 'stat, different wiring configurations/combos can be handled this way...AOD, are you old enough to remember how much of a PITA it was to work on heat pump control wiring back in the 70's-80's?
AOD
Addicted to ArboristSite
Born in 1981. I've worked on heat pumps installed in the late 80's when I lived in NoVA, since I moved to MI and got away from HVAC work I haven't messed with a heat pump in awhile.
We had mild winters here in the mid 90's and a developer decided to slap up some cheap azz condos right off of Lake MI and every one of them had air-air heat pumps with electric backup. I'd hate to live in one of them on a night when its windy and in the single digits, unless of course I had a wood stove!.
mtfallsmikey
Addicted to ArboristSite
Yah, my first one was an old York heat pump made around 1960...sold/serviced Comfortmaker, but worked on Rudd, Heil...worst was the old Westinghouse Hi-Re-Li. Every heat pump mfr. had a different control scheme; some powered the reversing valve in the cooling mode, some in heat....defrost timers with time wheels, etc. Things are a little more standardized now...don't miss working on a froze-up consenser myself!
mga
wandering
correct me if i'm wrong....but, don't the thermostats for those have settings for "normal" and "emergency"?
in conditions as you describe when it's too cold for the heat pump, they could manually swith to "emergency"...or, in other words...."electric" heat.
i'll bet those people hate them things. i've serviced similar units around here where they use only electric to heat and use the a/c units as a heat pump...until it gets too cold, then they switch to full electric.
mtfallsmikey
Addicted to ArboristSite
Yes they do..."emergency" position bypasses the condenser and runs the elevtric heat. Heat pumps can extract only so much heat from the outside air, that's where the second stage of the t-stat comes in...electric heat comes on to boost the outlet air temp, but most will only go to about 105-110 deg. output. heat pumps are ok if they are sized correctly, ductwork sized correctly...house constructed tightly, but I wouldn't have one in my house!
