Posts Tagged ‘boiler controls’
I have been asked over the years “What is a boiler horsepower” and what is the design criterion of square feet of heating surface per boiler horsepower.
We have written many articles about flame safe guard controls on Control Trends but we have not really given an explanation on the basic principles of these controls.
Stromquist and Company does not sell fire tube boilers but we do sell a vast amount of controls for these boilers from manufactures such as Conbraco, Honeywell, Asco, McDonnell & Miller, Maxitrol, and numerous other control manufacturers. The understanding of these boilers is a major concern in our continuing efforts to keep our readers informed.
FIRE TUBE BOILERS:
In a fire tube steam boiler, heat and gases of combustion pass through the tube surrounded by water. Fire tube boilers steam boilers maybe either high or low pressure boilers. The three types of fire tube steam boilers are horizontal return tubular boiler, scotch marine boiler, and vertical fire tube boiler.
Proper boiler blowdown is an essential part of firetube boiler operating proceedures. It is necessary to control the amount of TDS (total dissolved solids) in the boiler water.The total TDS should not exceed 3500 parts per million in a scotch marine boiler. If the blowdown is not controlled, excessive dissolved solids will have a tendency to increase and concentrate to a point that will cause a foaming or a carry over condition which will contaminate the steam.
The following is a list of what causes a LWCO switch to malfunction taken from the McDonnell & Miller Service Guide.
Fault codes are used on the Honeywell RM7800 series of boiler burner flame safeguard controls. These codes help the service technician identify problems that occur with the relay or the components that are wired to the relay.
Honeywell Burner Boiler Flame Safeguard Training Classes
Free Training! Free Training! The Stromquist/Honeywell Flame Safeguard Training Blitz is on. I recently posted about the classes being held in Tampa and Orlando, and since then we have added 8 more classes in 8 different cities. Read More
Honeywell has announced they are introducing a series of integrated combustion panels to go along with the awsome Delphi release from last year. These new panels will incorporate Honeywell’s proven combustion technology into complete panels, making equipment upgrades a snap! All panels will be pre-wired, pre-tested, and a built in a certified UL panel shop. Made in the U.S.A.
The initial offering will include: Read More
The Honeywell T775 Series stand alone controllers have now been on the market for several years. This diverse controller offers the technician a multitude of installation options on one small package.
This controller that stands 8 inches wide by 4 inches wide can be mounted anywhere within 1000 feet of its sensor location and be purchased as a standard enclosure or a NEMA 4X enclosure.
The T775 has an EEPROM that saves all values entered. The date and time values are retained for 24 hours after power loss. After power loss of more than 24 hours values may need to be reentered.
IMPORTANT: If a high limit set point is entered into a T775 controller this value is IRREVERSIBLE !!
Voltage: 24/120/240 note: cannot be used for DC voltages
Set Point Range: -40 to 248 F
T775A and B models: relay outputs from 1 SPDT to 4 SPDT (no analog outputs). Sensor inputs 1 to 2. Floating outputs 0-to 2
T775M models: Modulating with analog outputs of 2-10Vdc or 0-10 Vdc or 4-20 mA or Electronic Series 90. Relay outputs from 0 to 4 SPDT. 2 sensor inputs
T775R models: RESET OPTION.. 0 to 2 analog outputs 0 to 4 SPDT relay outputs. 0-2 floating outputs.
Sensors: update display and controller every 1 second
Accessories:
C7031D2003 5 inch immersion sensor with well
C7030B1009 wall mount room sensor
C7100D1001 12 inch Duct Averaging Temperature Sensor
When the need for a standalone controller presents itself think Honeywell and let Stromquist and Company help you select the right controller for your needs. Give us a call… Atlanta 1-800-241-9471 or Orlando 1-800-638-7828
The latest accurate information and demos on products
