I have a Ruud Silhouette furnace and air, what size filter do I need and the one there now is only about 1/4" thick, can I use a 1" thick filter?

SOURCE: How do you change the air filter on a Ruud silhouette II furnace?

If it is a down flow, it will usually be found in the return air plenum just above the blower. You need to remove the front panels and look inside above the blower. You may need to remove a second door to access the blower section. If it is an upflow, remove the bottom door and look alongside the blower where the return air comes in.

SOURCE: Ruud Silhouette II Gas Furnace, the furnace lights

Bad or dirty flame rod.
On a call for heat, the 24 volt thermostat sends a signal to the control module. The control module will indicate a call for heat with a light on the control either blinking or remain solid depending upon model. The inducer (exhaust) blower will purge all gasses from the furnace and pressurize a pressure switch. Once the pressure switch tells the module to continue, the electronic ignition will energize and send 120 volts to the igniter. The igniter will glow and you will be able to see it if viewed thru the small inspection port. Once the igniter gets hot enough, it sends a signal to the module opening up the gas valve (24 volts). Either a pilot will come on or the burner tube will ignite then spread the flame to all burners. Lastly a safety sensor will be looking for a certain temperature within a few seconds and the furnace will continue to operate and the room air blower will turn on in a minute or two.

What could go wrong? The unit will not run if there is no signal from the thermostat (bad thermostat or broken wire), the control module does not sense a signal from the thermostat (bad control), the inducer does not energize (bad motor), the pressure switch does not close (blocked vent piping, bad switch, plugged condensate hose), the igniter does not energize (bad control, bad igniter), the gas valve does not open or there is no gas (bad gas valve, broken wire, no gas), the pilot does not light (dirty pilot), the burner does not light (bad burner, plugged orifice, not enough combustion air), the flame does not spread to each burner (bad flame spreader, dirty flame spreader, more bad burners), the flame safety sensor does not detect flame (dirty or bad flame spreader, bad flame sensor, broken wire, bad control), or the room air blower does not energize (bad fan motor, bad control).

SOURCE: my ruud silhouette ii gas furnace is blowing

I have a Silloutte II and water is dripping from the furnase. New house to us but we are having hot and humid day and need to know the maitainance that is neede to rid the water from dripping. Is there a heating unit to evaprate the water ?? please advise me on options or things to check.

thanks Scott

SOURCE: my ruud silhouette II gas

are all the vents in the house full open?
is the flue vent pipes clean and un obstructed?

be sure none of your ductwork on the air return side is collapsing restricting airflow when the blower tries to run.

Is the draft inducer fan coming on?

could be a bad high limit switch.

SOURCE: My piolet light keeps going out on my Ruud

It may just need a thorough cleaning and servicing and/or the Thermocouple is going bad. I'm betting on both.