51
Safety Control Operation
Temperature Limit Control (Water Boilers) – The temperature limit control interrupts burner operation when the supply
water temperature exceeds the set point. Maximum allowable water temperature in a water boiler is 250F. The L4006A
will reset itself when the water temperature drops below the set point less the differential (typically 15F). Manual reset
water limit controls, such as the Honeywell L4006E, must be manually reset. For this reason, they should be set well
above the operating limit control to avoid nuisance boiler shut-downs.
Pressure Limit Control (Steam Boilers) – The pressure limit control interrupts burner operation when the steam pressure
exceeds the set point. Maximum allowable steam pressure is 15psi, however the pressure limits should be set below this
to prevent the safety valve from opening unnecessarily. Manual reset pressure limit controls, such as the Honeywell
L404C, must be manually reset. For this reason, they should be set well above the operating pressure limit control to
avoid nuisance boiler shut-downs.
Low Water Cut-off (Steam and Water Boilers) – Low water cut-offs interrupt burner operation if the water level in the
boiler drops below a safe level. Steam boilers may be equipped with two low water cutoffs so that there is a back up low
water cut-off if the first one fails to shut down the boiler in a low water condition. In this case, the back up low water
cutoff must be installed below the “operating” low water cut-off and is usually a manual reset type.
49
Summary of Contents for 32 Series and
Page 2: ...2 ...
Page 4: ...4 Figure 1 Base Model General Configuration 2 II Specifications ...
Page 13: ...13 11 Figure 4 Multiple Base Assembly ...
Page 15: ...15 13 Figure 6 Assembly Of Sections Figure 5 Use Of Nipple Gauge ...
Page 20: ...20 18 Figure 14 Exploded View Of Jacket Assembly ...
Page 24: ...24 22 Figure 19 All Air From Outdoors Using Horizontal Ducts Into The Boiler Room ...
Page 34: ...34 Figure 26 Typical Near Boiler Piping When Using A Boiler Feed Pump 32 ...
Page 35: ...35 Figure 27a Recommended Steam Boiler Piping 1 or 2 Supply Connections Gravity Return 33 ...
Page 36: ...36 Figure 27b Recommended Steam Boiler Piping 3 Supply Connections Gravity Return 34 ...
Page 37: ...37 35 Figure 27c Recommended Steam Boiler Piping 4 5 or 6 Supply Connections Gravity Return ...
Page 42: ...42 40 Figure 30 Typical Water Boiler System Piping ...
Page 49: ...49 47 Figure 35 Series 32 Standard Boiler Wiring ...
Page 50: ...50 48 Figure 36 Series 32 CSD 1 Boiler Wiring ...
Page 65: ...65 63 Figure 42 Exploded View Base Parts ...
Page 67: ...67 65 Figure 43 Exploded View Gas Manifold Burners Pilot Assembly ...
