Service manual
06/2010 
2.  On circuit board set T-set (blue test connector) to 2.0 volts (120F). 
3.  Set water flow  0.5 gpm (gas OFF) and verify the DSI function: 2.5 sec fire, 3.0 sec purge, 2.5 
sec fire, lockout. 
4.  Run AUTOCAL (SM500-15), if required. 
5.  Shutdown. Disconnect DSI flamesense feedback to board (see figure TS500-4) 
  Modulating valve voltage =  (0.0 vdc) 
  Manifold pressure =  (0.65 - 1.15 wci) 
  Verify gas stays at min. 
6.  Fail T-mid thermister. 
  Verify gas flow is shutoff. 
  System lockout (red LED double flashing). 
7.  Increase flow so that the burner is on maximum burn and T-out does not reach T-set. At this 
condition: 
   Modulating valve voltage = (> 10.0 vdc) 
    Manifold pressure   = (> 7.25 wci) 
8.  Setup steady flow conditions verify that the steady state variation is always within  2F. 
9.  Has the unit leaked water? 
 SM500-17 Winter  Protection 
 IMPORTANT  
 COLD WEATHER PROTECTION INFORMATION 
WARNING: 
Do not disconnect the electrical supply, 
turn off the propane supply or disconnect the cold pack 
power when temperatures are near or below freezing. 
The 
RV500 freeze protection system will not work if the 
electrical power source or propane is disconnected. 
Note: When driving in cold temperatures drain water 
from RV500 to avoid freezing. The freeze protection 
will not protect the unit from freezing while driving. 
WINTERIZING ______________ 










