Ruud Furnace, AC, auto thermostat, 20 years old

Hi,

I think I may have 2 issues/conditions.

1. Blower will not come on when TS set to Blower=On, or when TS commands cool.

2. Blower comes on by itself in summer.

A few years ago my blower limit switch was replaced and ever since then my blower just comes on by itself in summer, I assume this is no big deal and is caused by limit switch adjustment. Limit switch can turn on blower regardless of TS setting right?

Now my blower not coming on when cool command sent by TS, or when set to Blower=On. However blower still comes on by itself as described above.

If blower starts then capacitor is good right?

I am guessing Blower Relay is bad. I see a plate on left side, behind panel, that has transformer and I assume blower relay, sound correct?

I am very new at this, so forgive me is I have left out info or mis-named something. If my logic is off, please put me on the right track. BTW I can handle simple wiring and a VOM, and I have 2 units, upstairs and downstairs, I hate parts swapping, would rather test. I am wide open for experienced opinion.

Thanks very muchin advance. Help is greatly appreciated!!

Thanks, Danny