by Gary <gary@[EMAIL PROTECTED]
>
Jul 14, 2008 at 12:42 AM
> Yeah... use a simple SPST fan relay to control a 3 pole contactor....or
is
> that too simple??
No that wouldn't work.
What I'm doing is designing a relay system for a three zone system
with a three speed blower motor that will call for a different speed
depending on how many zones are in use.
1 zone - low
2 - zones - med.
3 - zones - high
Here is my diagram.
http://www.oldnewtimer.com/zone_three_speed.jpg
I have to use t-stats where the fan gets energized whenever
there is a call for heat or cool. If anyone sees any discrepencies let me
know. I haven't tried it out yet but will in a couple weeks.
