How can I delay fan turn-on

[wc9]

I'm getting one of the new Trane communicating systems installed. Issue is that I have hydro coils for heating and the system has no way to delay fan turn-on so I don't get cold air blowing out before the coils heat up. Traditional methods like an acquistat or separate relay won't work with the communicating unit that I have. Installer has talked to Trane support and apparently there is no solution. I can't believe Trane didn't account for this during system design. Has anyone encountered this issue before?

[stonefly]

there is a way to do what you ask but my guess is it would be a bad idea and probably void the warranty. it would cause a great deal more water press. at the begining of ea. cycle. as a rule higher efficiency systems are designed to "maintain" the temp. and are left on controlled by stat. program. older less efficient systems typically have more capacity and ability to "recover" the temperature. if operating normally the only time you should have cold draft is when the system has been off and the house is cold. do you turn it off at night? try a setback of 7-8 degrees (cooler at night) and see if it does'nt maintain that without the cold draft.

[wc9]

I should mention that my ductwork is in the attic so when it's 20 degress outside it's probably 40 or so in the attic. Thus, I would get chilly drafts anytime the fan is circulating air without the hot water coils being warmed up yet (which takes 2-3 minutes).

[beachtech]

can be programmed into the thermostat to delay the fon on time in heating :)