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   Furnace:
  
   The Rialta furnace is supplied by
  Suburban Manufacturing 
  Company of Dayton, Tennessee. The standard Rialta furnace model for the QD and HD is the Suburban NT-20SE which 
  interestingly enough is only rated at 19,000 BTUH.  All other models within the 
  product line have the two digits to indicate the actual BTUH. 
  On the FD, the furnace is model DD-17DSIW, ducted.  Both require 12V DC power to operate the controls and only burn Propane.  There 
  are no 110V AC power requirements for the furnace, fan, or thermostat controls. 
  
  
    
      | Model Number | BTUH Input | Height | Width | Depth | Voltage | Amp. Draw | Ship Wt. | Unit Wt. |  
      | NT-20SE | 19,000 | 9 3/8" | 9 3/8" | 21-27 3/4" | 10.5-13.5V DC | 2.8 | 27 lbs. | 22 lbs. |  
      | DD-17DSIW | 17,000 | 12" | 10 1/2" | 22-29" | 10.5-13.5V DC | 2.9 | 25 lbs. | 20 lbs. |  Problem Areas:
  Please note that the controls and fan on the furnace only run 
  on 12V DC. If you are "dry camped" and allow the furnace to run frequently all 
  night long, in very cold areas you will likely find your coach auxiliary batteries 
  almost dead by the morning. You'll notice the furnace fan slowing down and starting 
  to make unusual noises. Running the engine or generator will quickly recharge 
  them and no harm is done. The furnace uses an electric igniter to start the combustion 
  process and no "pilot light" is used. It also incorporates a "sail switch" which 
  means the gas is not turned on until the fans blow air into the combustion box 
  and exhausts any possibility of a previous gas build-up. If you listen closely 
  when you turn on the furnace you'll first hear the fan operate for a few seconds 
  and then the ignition of the gas begins. If the fan does not come on to expel 
  any accumulated gases in the combustion area, then the electric ignition is prevented 
  from occurring. Also note the two furnace vents that are required to be in 
  the exterior skin of the Rialta. One is a "fresh air intake" and the other is 
  the "exhaust vent". If you live in an area that frequently has "mud wasps" or 
  other such insects that have a habit of building a nest in little confined areas 
  such as in these tubes, then you should consider covering these vents with a suitable 
  metal screen material. Suburban does not recommend covering these vents but you 
  have to be the judge if the problem warrants such coverings. If your furnace is blowing nothing but cold air, then it probably 
  is in lock-out mode or the limit switch has opened and not reset, or the sail-switch 
  has detected that the fan failed to come on first. Lock-out occurs when a problem 
  exists during the trial for ignition. Your dealer or a Suburban service center 
  should be consulted to diagnose this condition. [ return to top ]     
   
   Furnace FAQs
  
    
      | Questions & Answers If you've got questions about your Suburban 
      RV furnace, check out this list of questions frequently asked by customers. 
        
          | 
 Question 1
 Can I repair my furnace myself?
 
 Answer:No. Never attempt repairs yourself. The unit must be serviced by a 
          qualified installer, service agency or gas supplier. Improper installation, 
          adjustment, alteration, service or maintenance can cause property damage, 
          personal injury or loss of life.
 |  
          | Question 2 If I have a product problem, how do I get service?
 
 Answer:First, if your RV has its original furnace and is still under the 
          RV manufacturer's warranty, follow the steps described in your RV owners 
          manual. Second, contact a conveniently located Suburban Recommended Service 
          Center. A list of such service centers is located in this section of the 
          web site. Describe to them the nature of your problem and make an appointment 
          to have the problem corrected. Third, you and the service center can contact 
          Suburban's Customer Service Department at P.O. Box 399, Dayton, Tenn., 
          37321, or call us at 423-775-2131 if more assistance is needed.
 
 |  
          | Question 3 Where can I get parts for my furnace?
 
 Answer:Genuine Suburban replacement parts are available from Suburban service 
          centers. If the service agency does not have the merchandise you need 
          in stock, they can order for you. If there is no Recommended Service Center 
          in your area, you may contact any local RV dealer or service agency for 
          assistance. Suburban sells through most RV wholesalers, so the local agency 
          should be able to order parts for you through their normal source.
 |  
          | Question 4My service company/dealer has generic parts for my furnace that cost 
          less. Are these parts OK?
 
 Answer:Use of generic replacement parts is not recommended or approved by 
          Suburban. Our first concern is your safety. Second is our concern over 
          product performance and customer satisfaction. When you install a non-Suburban 
          part, we can guarantee neither. Be aware that use of non-Suburban parts 
          will void the warranty and you will assume liability consequences. It 
          also violates the intent of the UL, CUL, AGA or CGA certifications.
 |  
          | Question 5 Can I use my furnace while driving?
 
 Answer:No. Suburban does not feel this is a safe practice. Some states have 
          laws forbidding the use of propane while driving. You should be sure all 
          gas appliances are off and their ignition systems are off while the vehicle 
          is in motion or being towed.
 |  
          | Question 6 Is it safe to install a bug screen over my furnace vent?
 
 Answer:No. Suburban does not approve - nor do we recommend - using the aftermarket 
          screens being sold to cover the outside vent cap. This restricts the exhaust 
          and intake air, resulting in improper burner operation and a potentially 
          unsafe condition.
 |  
          | Question 7My current furnace needs to be replaced. What BTUH size should I buy 
          to replace it?
 
 Answer:Check your furnace data plate for BTUH input. The replacement should 
          be the same BTUH size or a close equivalent. Do not oversize your furnace. 
          Too much heating capacity leads to rapid cycling and reduced comfort levels. 
          If you do choose a larger BTUH furnace, your installer must make sure 
          the installation requirements meet or exceed Suburban's installation requirements 
          for ducting, return air, clearances and gas pipe size.
 |  
          | Question 8 Is there any preventative maintenance required on furnaces?
 
 Answer:Yes. We recommend an annual inspection by a qualified service technician. 
          Also, you as the owner/user should inspect the furnace monthly during 
          the heating season for the presence of soot on the vent. Operating the 
          furnace in this condition could lead to serious property damage, personal 
          injury or loss of life. If soot is observed on the vent, immediately shut 
          down the furnace and contact a qualified service agency.
 |  
          | Question 9Can I close off a register so more heat goes to another part of the 
          vehicle?
 
 Answer:No, this is not recommended. Doing so will cause improper furnace 
          operation and possible overheating of the furnace.
 |  
          | Question 10 What causes the majority of furnace problems?
 
 Answer:Conditions that can affect the performance of your furnace can include:
 Low gas pressure caused by a number 
            of factors, including a malfunctioning regulator or low gas levels in 
            the tank. This can only be tested by a qualified service technician. Low voltage, which again can only 
            be checked by a certified service technician. Inadequate ducting. Have your 
            dealer make sure the furnace has at least the minimum number of ducts 
            and required duct area (min. sq. inches), excluding closeable outlets. 
            Check for proper duct connections at the furnace or collapsed ducts. 
            Make sure ducts are clean and clear of obstructions, and are as straight 
            and tight as possible. Restricted or insufficient air 
            return: the return air passage should meet the minimum open square inches 
            as specified for the particular model of furnace installed. It must 
            not be blocked or restricted. Keep the furnace compartment clean of 
            any materials that can block the air flow around the furnace. Unauthorized alterations and improper 
            reinstallations. Failure to adhere to the preventative 
            maintenance measures outlined in the users manual.  |  
          | Question 11 My furnace runs, but it's just blowing cold air. What's wrong?
 
 Answer:Your furnace is in lock-out or the limit switch has opened and not 
          reset. Lock-out occurs when a problem exists during the trial for ignition. 
          Your dealer or a Suburban service center should be consulted to diagnose 
          this condition.
 
             
  |  |  
  [ return to top ]     
   
   Thermostat:
  
   The 
  wall mounted thermostat is made either by 
  Robertshaw Controls Company or beginning in the 2003 model year also by
  Suburban Manufacturing. 
  Both types are typical of most inexpensive thermostats used in RVs. Its only function 
  is to determine the surrounding air temperature and signal the furnace to turn 
  on or off depending upon your desired temperature selection. In the Rialta, it 
  operates only on 12V DC and there are no 120V AC wires involved in its operation. There are two minor  problems with the Robertshaw thermostat. 
  First, the thermometer is not only very difficult to read but is known to be somewhat 
  inaccurate. There is a thermometer calibration procedure outlined in the "Installation 
  Instructions" sheet included with the new Rialta papers, but most people end up 
  moving the selector lever to wherever they "feel" is the most comfortable without 
  actually looking at the temperature read-out.  The second problem is that the on-off lever located on the 
  bottom moves very stiffly over its limited total travel of approximately 1/4". 
  You may think that the furnace is off when it really is not, or vice-versa. The 
  letters indicating on-off are very hard to read so sometimes you must physically 
  move the lever to make sure it is in the desired position.  The thermostat does NOT have to be installed perfectly level 
  and will operate in all positions when wired correctly. The only user service 
  possible concerns the contacts where the temperature control makes or breaks the 
  circuit. Robertshaw recommends the use of any unglazed paper sandwiched between 
  the contacts and moved back and forth to polish the contacts and remove any tarnish 
  buildup. Most "back-yard" mechanics will use a small piece of fine emery cloth 
  or even extra-fine sandpaper to clean the contacts. [ return to top ] |