Pre-1995 Suburban RV water heaters have an adjustable air-shutter valve control. These models use a Robertshaw or Unitrol control unit. Suburban RV water heaters with SIT control units made after 1995 cannot adjust the air flow, as it is preset at the factory. An authorized Suburban repair facility can change the air flow orifice on the newer SIT models if the RV is used primarily at elevations greater than 4,500 feet.
Instructions
1. Open the panel to the water heater. Verify the type of control unit on the Suburban RV water heater. Unitrol models have the name on the front of the control unit. This unit has a reset button and gas cock on the top of the control unit.
The SIT control unit does not have the name on the front. SIT units have a gas cock on the left top of the control unit. There is no reset switch on the top of the SIT control unit. These control units do not have an adjustable air-shutter valve.
2. Make sure there is ample propane gas in the tanks. Verify the hot water tank is filled prior to turning on the unit. Start the water heater.
3. Locate the air-shutter valve under the control unit. Loosen the shutter locking screw. Slide the valve so it is one-fourth of the way open. This should cause the flame to burn mostly blue with a yellow tip.
4. Adjust the air-shutter valve by sliding it open or closed if the flame is too yellow or too blue. There should be a small yellow tip on a blue flame.
5. Listen to the flame; there should be some sound but not a loud, roaring sound. A roaring flame has too much air. Slide the air-shutter closed until the roaring is reduced. Tighten the shutter locking screw to hold the air-shutter in place.
Tags: control unit, air-shutter valve, Suburban water, adjustable air-shutter, adjustable air-shutter valve, control unit Suburban, control units