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Control Valves. Liquid Level Control. Pressure Control. Temperature Control. Glycol Pump. Temperature Controllers. Indirect Thermostat. Negative feedback for linear output. 5 to 30 psi air or gas supply pressure. Stainless steel housing. Bi-metal sensing element
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Control Valves Liquid Level Control Pressure Control Temperature Control Glycol Pump
Indirect Thermostat Negative feedback for linear output 5 to 30 psi air or gas supply pressure Stainless steel housing Bi-metal sensing element for accurate control Single adjustment over Wide temperature range: T 12 -30 to 400oF HT 12 -30 to 700oF Output pressure proportionate to temperature at any setting T12
? Direct or Indirect ? Direct Mode Indirect Mode Rising Temperature Rising Temperature Rising Output Falling Output Direct Indirect
Indirect Thermostat Indirect
Thermostat with Separable Socket Maximum Working Pressure Without Separable Socket 500 psi With Separable Socket 4000 psi With Special Separable Socket 7000 psi
Direct Acting Thermostat Supply Output T 12DA Direct
T 12DA Thermostat Reversed for Indirect Throttle Mode Supply Output Indirect
High Temperature Thermostat Supply HT 12 Output Indirect
Direct Snap Thermostat T 12S Output Supply Direct
Indirect Snap Thermostat T 12DAS Output Supply Indirect
Indirect Throttle Thermostat T 12T Output Supply Indirect
Direct Throttle Thermostat Output T 12TDA Supply Direct
Direct Semi-Throttle Thermostat T 12DAT Output Supply Direct
Indirect High Temperature Shut-Down T 12M Output Supply Indirect
Direct Low Temperature Shut-Down T 12DAM Output Supply Direct
High Temperature Pilot Guard Supply HT 12PG Output Direct
Typical Installation High temperature shutdown thermostat Burner control thermostat Burner valve Main burner Safety shutdown valve Pilot Pilot Guard thermostat Instrument Gas
Typical Burner Control Installation Low liquid shutdown pilot High temperature shutdown thermostat Burner control thermostat Main burner Pilot Instrument Gas Pilot Guard thermostat Safety shutdown valve Burner valve
Trouble Shooting SYMPTOM CAUSE • Bent sensing element • (element should be centered • in base and should “ring”) • Incomplete immersion of probe • Dirty pilot plug seat • Hole in diaphragm • Weak pilot plug spring • Faulty ‘O’ ring • Erratic temperature changes • Continuous venting
Trouble Shooting • To check small seat: increase temperature setting • several degrees and see if venting stops. • To check large seat: decrease temperature setting • several degrees and see if venting stops. • Replace pilot plug and seats if unable to stop venting • by cleaning seats.