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Exquisite Heat. For Steam Boilers. Time based system. Thermostat Demand Analysis over time will determine the length of burner fire time of the boiler. This will remove the leads and lags associated with the over and under heating in steam boiler comfort. Fire timing.
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Exquisite Heat For Steam Boilers
Time based system • Thermostat Demand Analysis over time will determine the length of burner fire time of the boiler. • This will remove the leads and lags associated with the over and under heating in steam boiler comfort.
Fire timing • Programmable limits of maximum and minimum burner fire times. • Time limit minimums will avoid short cycle. • All firings are thermostat initiated, and controlled by system pressure limits. • Start up fire times are determined by how long it takes to meet system pressure controls.
Fire time adjustments • As the controller demand analysis (previously discussed) resets fire times, from hour to hour. Burner fire time will be increased or decreased in order to meet the ideal thermostat demand ratio. (60%). On mild days this may well allow comfort satisfaction at lower than system set pressure limit at the boiler.
Algorithm Start-up fire time = the time it takes to satisfy pressure limit from a cold start. (15-90 minutes) Boiler pressure controls and thermostat satisfaction can over ride the initial start up time.
Proper Boiler Firing • It is important to know that the boiler should be making steam within the 90 minutes. If the pressure is not made: • Check boiler burner rate is high enough to produce good steam. • Check pressure gauges and pressure control. • Check piping insulation, vents, traps, condensate return lines, flue gas analysis, and boiler water level.
Minimum burner fire time • The amount of time it takes to recover to steam delivery after a break. • 10-40 minutes • Minimum = Fire Time 10 min.
Alternative Break Time • In addition to a fixed break time, a proportional break is provided if convenient.
Break between fire times Fire Time * .3 If burner time is calculated to 40 minutes the break will be (40*.3 ) =12 minutes. If burner time is calculated to 12 minutes the break will be 10 minutes. (remember minimum)
Alternate break method • The break time can be a fixed time or proportional. • Each building has its own rhythm. • Factory settings can be adjusted if needed by the installer.
Break time • The goal is to have the thermostat satisfied into the break. • There are savings and comfort advantages as the thermostat is satisfied after the burner is off. • The thermostat overrides all calls for burner firing.
Start up Time • If the thermostat does not call for heat more than for one hour the controller adjusts fire time back to Start up time, which will be initiated by thermostat activation. Should the thermostat be satisfied at any time the boiler will be shut down. The controller will take this into consideration in the next calculation.
All variables are changeable • Maximum Burner Time 15-90 minutes • Break time ratio .2, .3, .4, .5, of Burn time • Minimum Break .3 max Burn time • Fixed break time for condensate. • Start up burn time: 20, 30, 45, 60, 90 min. • Min Burn time : .3 burn time or ten minutes. • Ideal demand ratio .5, .6, .7, .8 • Analysis time: 40, 60, 90 minutes
Algorithm • Thermostat activity analysis within the hour will determine the increase or decrease adjustment of the burner fire time in the following hour. • Actual demand ratio vs. Ideal demand ratio determines + or - to length of fire on time, adjustment from previous hour calculated fire time.
Fire Time change • Actual demand ratio = 70 • Ideal Demand ratio = .60 • (.70-.60)=.10 x 10= 1 time change factor • Time increment factor= 2 minutes • Previous hr. fire time 30 minutes • 1 time chg.. factor x 2 min = +2 min • Prev. fire time 30min + 2 min= 32 min • New Burner fire time 32 min (increase)
Steam Systems require annual maintenance inspection and service by a professional steam expert and periodic weekly owner system checks.
Weekly Checks • Boiler water level. 1/3-1/2 water in fill glass • Pressure monitoring .5-2.0 lbs • Blow down auto refill devices to remove rust • Watch it cycle for a full two firings to verify pressuretrol safety operation. Check for short cycling. • Check for continuous boiler firing. (longer than 40 minutes) This means you need to talk to your boiler service to explain. • Check that all radiation is getting steam.
System Service • Steam is delivered as soon as it is generated. Traveling at great speed it will satisfy BTU demand quickly. It is most important that all system components are in good working order as designed. It can not be overemphasized, that complete inspection service and repair maintenance be done, annually by a professional.
Boiler Firing • Boiler firing rate and oil nozzle size must be proper for the boiler to have efficient heat exchange from the fire to the waterside. If the nozzle is too small the boiler will take forever to heat. Steam pressure should be met in less than 30 minutes. If not have the boiler fire size checked by a professional boiler person. See manufacturers suggested gallons / hour. This information can be found at manufacturers website.
System Insulation • Many systems have had the asbestos insulation removed. Few replace the insulation due to the added expense. With fuel prices going up, insulation return on investment is becoming very attractive. The system was designed to work with insulated pipes. • Most steam systems can be reinsulated for 5 dollars per pipe foot. • You are wasting the heat in the pipes if you do not.
System Components • Proper boiler piping measurement check. • Testing cleaning and repair of: • air vents, traps, safety controls, chimney inspection, flue gas analysis, heat exchange cleaning, make up water supply rate, piping insulation, condensate return systems and boiler water, fuel supply and storage. • Proper venting of boiler room for fresh air and fire prevention.
Outdoor temperature • This is already compensated for by the Exquisite Heat indoor reset technology that adjusts the boiler for the precise replacement of heat at the thermostat. The thermostat takes all heat loss into consideration from inside the building where the people are.
References • We strongly urge all owners and managers of steam systems to begin their search for complete information about their steam heating equipment with a visit to Dan Holohans’ web site : • http://www.Heatinghelp.com • Dan has a great library from beginner to advanced for heating information.
Comfort • Steam heat now has the opportunity to be comfortable and efficient with the intelligent management offered by Exquisite Heat control. • www.Exqheat.com 914-588-4791 • John Cockerill US Patent: 6,402,043 • Rev 09-09