T103 has 120Volt clock motor, so we can wire this timer
T103 timer is rated for 30 amps and 2horsepower and your blowers use 28 amps.
So we're getting close to max on the timer. Hopefully blowers won't all be started at one time since motors draw maximum amperage when they start.
However, you need 30 amp breaker and orange 10 gauge wire for that much amperage >> unless only one blower is turned ON at any given time.
Always match wire size, amperage of breaker and amperage of Load or it will trip the breaker.
If you put 30 amp breaker on size 10 wire it is good. But 30 amp breaker on smaller size 14 or 12 gauge wire is fire hazard.http://waterheatertimer.org/Color-codewire.html
Add a comment at any time, and I will respondLook at the basics
You have 2 cables.
One cable comes from breaker box.
Other cable goes to three 120V plugs (120V is same as 110V).
Each cable has black-wire, white-wire and bare-copper-ground-wire.How to wire the timer
Timer has 5 terminals: A 1 2 3 4
A) Cable from breaker box:
White wire from breaker connects to terminal A
Black-wire from breaker connects to terminal 1
B) Cable going to 3 plugs
Black wire to plugs connects to terminal 2
White wire to plugs connects to terminal A
Ground wires connect to green ground screw.
Terminals 3 and 4 are not used in this case.
Here is a wiring diagram that shows 120Volt from breaker box and 120Volt going to Loadhttp://waterheatertimer.org/How-to-wire-T104-Intermatic-timer.html#T103