Giantsean
Member
Hi All... hope you can pardon the strange questions here, but I'm really trying to figure out my next move. I have a hydrocoil forced air install which is just about to face it's first full winter. I have an AS branded Trane TAM7 with a Navien boiler. My installers are Rheem guys and happily took my money to put in the AS without really understanding how to set it up, but that's a whole other story.
Now I have it tweaked to my satisfaction, I am looking to upgrade from the cheap stats which they provided (as well as a zone controller which was made for heat pump.. I don't have a heat pump. Another whole other story). I noticed the TAM7 supports multistage heating via terminals W1-W3. Jumping them makes fan blow fast. NOT jumpering them makes fan blow so slowly that the house will never get warm. I know there are some thermostats (Nest comes to mind) that have separate W1-W3 terminals. I also know that in heat pump setups these are often configured for different things, like AUX/EM or various stages of electric supplemental heat within the A/H.
My question is, is it worth getting stats which support W2/W3 for a hydro air handler? W1 does almost nothing by itself. I have not tested W2 extensively but W3 does the job by sheer force. What I am not sure about is by what logic the thermostats will try stepping up to a higher heat level. Is it based on temp over time? Also, when a thermostat calls for more stages, does it only energize that particular stage or does it do so sequentially? For example during a 3rd stage call are all "W's" energized, or only W3?
Again, it seems to work ok but I'd love to take advantage of the full capabilities of the system. Thanks for any advice!
Now I have it tweaked to my satisfaction, I am looking to upgrade from the cheap stats which they provided (as well as a zone controller which was made for heat pump.. I don't have a heat pump. Another whole other story). I noticed the TAM7 supports multistage heating via terminals W1-W3. Jumping them makes fan blow fast. NOT jumpering them makes fan blow so slowly that the house will never get warm. I know there are some thermostats (Nest comes to mind) that have separate W1-W3 terminals. I also know that in heat pump setups these are often configured for different things, like AUX/EM or various stages of electric supplemental heat within the A/H.
My question is, is it worth getting stats which support W2/W3 for a hydro air handler? W1 does almost nothing by itself. I have not tested W2 extensively but W3 does the job by sheer force. What I am not sure about is by what logic the thermostats will try stepping up to a higher heat level. Is it based on temp over time? Also, when a thermostat calls for more stages, does it only energize that particular stage or does it do so sequentially? For example during a 3rd stage call are all "W's" energized, or only W3?
Again, it seems to work ok but I'd love to take advantage of the full capabilities of the system. Thanks for any advice!