# MEMORANDUM
To: Carl Ad- and 

### Kathi 

### Epping, DOE
Prom: 

### Greg Rosenquist, 

### LBNL Subject: Gas 

### Range Ignition Control Systems
Date: 

### April 30,1998 

### This memo discusses operational 

### and safety issues pertaining to gas 

### range ignition control systems. 

### The information presented 

### in this memo came 

### from phone convexsations with two different stafF members (Joe Erdelsky 

### and Morgan Reynolds) at Siebe Appliance Controls 

### during 

### the first

### week of 

### April. SiebeAppliance Controls was 

### recentlypurchasedby 

### Robershaw. Theresidential controls division of Robertshaw was 

### moved under 

### Siebe Appliance Controls. Robertshaw dso recently purchased 

### Baton's appliance controls divisions. These former Eaton divisions were also rnoved under Siebe 

### Applihce Controls, With these recent acquisitions, Robertshaw now supplies gas 

### ignition control systems to approximately70 

### to 80%

### of 

### the gas 

### range market. 

### Ignition Safety 

### hue for Gas 

### Ovens


### The safety concerns for standing pilot and electronic 

### ignition gas 

### oven control system are virtually identical. 

### nus, replacing a 

### standingpilot ignition system with 

### melectronically-based system does not create any 

### additional safety concerns. The following provides a detailed description of both standing pilot and electronic ignition gas 

### oven control system. Sranding 

### Pilot Ignition 

### Standingpilot control systemsforgas ovens 

### utilize what aretermed

### dualpilot control valves. 

### '1n the 

### standby mode, thepilot's rate ofconsumptionis approximately 

### 150BW, 

### In the

### heuter mode, 

### the pilot's rate of consumption is between 150 

### to 

### 800 BNhr. When, the user selects a 

### high oven temperature setting (>200°F),

### the pilot's rate 

### is suddentlyboosted fiom its standby 

### mode of 150 

### Btulht 

### to its highat 

### heater mode 

### rate of 800

### BWhr. At 

### pilot rates exceeding 

### 300 to 600 

### Btu/hr, a 

### safety valve opens withinthe 

### main gas 

### valve allowing

### gas flow tothemuin 

### burner. Once gas 

### flows to 

### the 

### mainburner, the 

### pilot 

### (in itsheater

### mode) ignitesthe

### mainburner. 

### A sensing

### bulb, equivalent to a 

### thermopile, senses whether 

### thepilot's consumptionis at a 

### high rate 

### (300 to 

### 600Btu/ht). If the 

### pilot is forsomemasoliextinguished, the 

### sensingbulb and

### its accompanyingcontrol

### mechanism will not allow gas to flow to the 

### main bmr 

### j&houizh gas 

## will continue to flow to the 

### pilot.


### If the oven themostant is 

### set ro a low oven ~mperalwe setting 

### (<200"F), 

## the pilot 

### will modulate (from 

### 150to 800

## BW) along with the

### main burner to meet 

### the desired 

### oven temperatme, Asjust mentioned, the 

### oven safety 

### valve begins 

### to open at rates between 300

### to 

### toBtumt, 

### The actual

### rate which the 

### safety valve opens depends on 

### the control strategy that 

### the 

### oven manufacturer wants 

### to employ.**900~** 

## MEMORANDUM

To: Carl Adams and 

### Ka.thi Epping. DOE


### From: Greg Rosenquist. 

### LBNL Subject: Gas Range Ignition Control Systems


### Date: April 30, 1998
This memo discusses operational and safety issues pertaining to gas range ignition control systems. The infonnation presented in this memo came from phone conversations with two different staff members (Joe Erdelsky and Morgan Reynolds) at Siebe Appliance Controls during the first week ofApril. Siebe Appliance Controls was recently purchasedbyRobershaw. Theresidential controls division of Robertshaw was moved under Siebe Appliance Controls. Robertshaw also recently purchased Eaton's appliance controls divisions. These former Eaton divisions were also moved under Siebe 

### Appliance Controls. With these recent acquisitions. Robertshaw now supplies gas ignition control systems to approximately 70 to 80% of the gas range market. 

### Ignition Safety Issues for Gas Ovens
The safety concerns for standing pilot and electronic ignition gas ovencontrol systems are 'Virtually identical. Thus, replacing a standing pilot ignition system with an electronically-based system does not create any additional safety concerns. The following provides a detailed description of bOth standing pilot and electronic ignition gas oven control systems. Standing Pilot Ign;rion Standingpilot: control systems for gas ovens utilize what are termed

### du.al pilotcontrol valves. 'In the strJ.n.dby mode, the pilot's rate ofconsumption is approximately 150 BtuIhr. 

### In the 

### heater mode, the pilot's rate of consumption is between 150 to 800 BtuJhr. When the user selects a high oven temperature setting (>200"F). the pilot's rate is suddently boosted from its 

### stan4by mode of 150 Btulhr to its highest 

### heate,. mode rate of 800 BtuIhr. At pilot rates exceeding 300 to 600 BtuIhr, a safety valve opens within the main gas valve allowing gas flow to the 

### "uz:in. bu.me,.. Once gas flows to the mainburner, the pilot (in its 

### heatermode) ignites the mainburner. A sensingbulb, equivalent to a thermopile, senses whether 

### the pilot's consumption is at a high rate (300 to 600 BtuIhr). Ifthe pilot is for SOIlle reasonextinguished, 

### the sensingbulb andits accompanying control mechanism will not allow gas to flow to the main burner although gas will continue to flow to the pilot.


### Hthe oven thermostant is set to a low oven temperature setting (<200oF). 

### the pilot 

### will modulate (from 150 to 800 BtuIbt) along with the main burner to meet the desired oven temperature. Asjust mentioned, the oven safety valve begins to open at rates between 300to 600 Btu/hr. The actual rate which the safety valve opens depends on the control strategy that the oven manufacturer wants to employ.

lNal ([V3 9669 98t OlS XVd SS:Ol ([3M 66/6l/S0

### Iffor somemason the pilot light gets extinguished,gas will

### continueto flow to the pilot. 

### Depending on the thermostat setting, 

### the rate of release 

### will be 

### any where: from 

### 150to 800 

### Btulhr. If 

### the 

### user sets the thermostat to a 

### high 

### temperature setring resulting in gas 

### flow to 

### the piloc equivdent to its higbest heater mode setting (800 

### Btulhr), there is nothing 

### in 

### the control 

### systemto stop the 

### flow of 

### unburned gas to 

### the pilot. Presumably the user will

### checkthe 

### oven's operation 

### oncethey 

### realize the oven is not gettinghot. But in case they do not check 

### the oven, 

### an 800

### Btu/hr flow ofunignited gas 

### does 

### not violate existing safety standards. According to 

### ANSI Standard Z21.1, 

### an 800 

### BNht 

### unignited gas 

### flow uri&in an oven 

### does not pose 

### a safety 

### hazard.
Electronic Spark-to-PilotIgnition 

### Spark-to-pilot

### ignition syst~ms operate very 

### similarto standing

### pilot systems, Rather 

### than

### utilizing a standingpilot, a 

### sparkignitor

### is 

### used to 

### light the pilor 

### (and in turn 

### light the main burner) when

### the 

### oventhemostatis activated. Once the

### pilot 

### is lit,the 

### spark-to-pilot 

### ignitionsystemfollows the sme operational 

### procedure 

### as described 

### above for standing pilot systems. If 

### the spatk ignition system was 

### not able 

### to light 

### the pilot, 

### like the 

### standing pilot system, the maximumrelease of unignited gas 

### would 

### be at 

### arate of 

### 800

### BtiJhr. As 

### stated above, 

### this continual release of gas would

### not violate

### ANSIZ2 1.1 

### safety standards. But

### the

### continualreleaseof 

### gas

### would be 

### unlikely as 

### the audible "clicking" sound of the 

### spark ignitor trying to light 

### the 

### pilot would alert the 

### user that somethingwas 

### wrong with the ignition system. The control system

### utilizes areignition chuit

### which sends 

### a 

### signal to the spark ignitor to 

### try and 

### ignite 

### the pilot 

### as long 

### as the pilot 

### is not lit. Presumably 

### the 

### user would set 

### the thermostat

### in the

### offposition to stop 

### the "ckcbg" sound 

### and prevent the flow of gas 

### to 

### the pilot. 

### Spark Electronic 

### Ignition 

### Control Systems for 

### Gas Rangtxi Spark electronic ignition control systems 

### for gas 

### rmges utilize a 

### control module to light the burners 

### at the 

### coolnap and the ovcri, 

### The control module for this systern 

### utilizes what 

### is temd

### a 2+I 

### control 

### module. The first value, 

### 2, represents the 

### number of 

### manual 

### spark i@tors 

### at the 

### cooktop. 

### The ignitow are 

### kmed manual 

### because the

### user must manually reset the themostat knob 

### in 

### order to refight

### the cooktop burners if 

### they become extinguished. 

### The second value in the 2+1 

### control 

### module, 2,

### reprasenu the 

### number of 

### reignition 

### circuits 

### in the 

### gas 

### range. 

## In this case, the 

### reignition circuit is for the oven 

### and it follows 

### the same 

### operational procedure 

### asjust 

### described above. The 

### cooktap does 

### not 

### require areignition system as 

### tbeuser has 

### visual recognition of when the 

### burners are 

### ignited. 

### Typical 

### Non-Standfng Pilot 

### Ignition Systems

### for Gas Ranges Spark electronic 

### ignition control systems 

### (forboth the cooktop and 

### oven) are 

### typically not 

### used in gas 

### ranges. 

### Rather, the 

### typical non-standing pilot 

### ignition system consists of 

### an electric glo-bar ignitiondevicefor

### theoven and a

### separate electronicspark-tocbmerignition systemforthe cooktop. For the cooktop, 

### the 

### spark ignition control 

### system wit1 typically be one that uses 

### a 2+0 

### control

9669 98P OTO XVd 99:OT 

### a3114 66/ZT/OO LoOIEJ 

### Iffor somereason the pilot light gets extinguished, gas will continue 

### to flow to thepilot. Depending on the thennostal setting, the rate ofrelease will be any where from 150 to 800 Btulhr. Ifthe user sets the thermostat to a high temperature setting resulting in gas flow to the pilot equivalent to its highest 

### heater mode setting (800 Btulhr), there is nothing 

### in the control system to stop the flow of unburned gas to the pilot. Presumably the user will cheekthe oven's operation oncethey realize the oven 

### is not getting hot. But in case they do not check the oven, 

### an 800 BtuIhr flow ofunignited 

### gas does not violate existing safety standards. According to ANSI Standard Z21.1, an 800 BtuIhr unignited gas flow within an oven does not pose a safety hazard.
Electronic Spark-to-Pilot Ignition Spark-to-pilot ignition systems operate very similar to standing pilot systems. Rather thanutilizing a standing pilot. a spark ignitoris used to light the pilot (and in tum light the main burner) whenthe oventhennostatis activated. Once the pilotis lit, the spark-to-pilotignition system follows the same operational procedure as described above for standing pilot systems. If the spark ignition system was not able to light the pilot, like the standing pilot system. the maximum release ofunignited gas would be at a rate of 800 BtuIhr. As stated above. this continual release ofgas wouldnot violate ANSIZ21.1 safety standards. Butthe continualrelease ofgas would be unlikely as the audible "clicking" sound ofthe spark ignitor trying to light the pilot would alert the user that somethingwas wrong with the ignition system. The control system utilizes a reignitioll circuit which sends a signal to the spark ignitor to try and ignite the pilot as long as the pilot is not lit. Presumablythe user would set the thennostat 

### in the offposition to stop the "clicking" sound and prevent the flow of gas to the pilot. 

### Spark Electronic Ignition 

### Control Systems 

### for Gas Ranges Spark electronic ignition control systems for gas ranges utilize a**~** control module to light the burners at the cooktop and the oven. The control module for this system utilizes, what is termed a 2+1 control module. The first value. 2, represents the number of manual spark ignitors at the cooktop. The ignitors are termed manual because the usermust manuallyreset the thermostat knob in order to relight the cooktop burners 

### ifthey become extinguished. The second value in the 2+1 control 

### mod1l1e.l. represents the number ofreignition circuits in the gas range. In this case, the reignition circuit is for the oven and it follows the same operational procedure as just described above. The cooktop does not require a reignition system as the user has visual recognition ofwhen the bUrners are ignited. 

### Typical Non-Standing Pilot Ignition Systems for Gas Ranges Spark electronic ignition control systems (for both the cooktop and oven) are typically not used in gas ranges. Rather. the typical non-standing pilot ignition system consists of an electric glo-bar ignition deviceforthe oven and a separateelectronic spark-to--bwnerignition systemforthe cooktop. For the cooktop, the spark ignition control system wUl typically be one that uses a 2+0 control



### 2

1Na1 ([V3 9669 9st 0IS XVd 9S:0I ([3M 661ZI/S0

### module. 

### The first value, 2, represents the 

### number ofmanual 

### sparkignitors 

### ~hile the 

### second value, 0, 

### represents 

### the number of 

### reignition circuits. Reigntion circuits are not 

### ded as 

### the user 

### bas visual recopition 

### of when the 

### burners are 

### ignited. 

### High-end (i.e,, 

### more expensive) gas 

### range cwktopswill use

### ignition systems

### utilizing a 01-4

### control

### moduk. Asjust 

### described,the 

### first

### value, 0, 

### representsthe 

### number ofmanual 

### sparkignitors 

### while the 

### second value, 4, 

### represents the 

### number of 

### spark ignitors 

### with leigaition ckuits. 

### Thus, if any 

### of the gas 

### cooktop 

### burners become extinguished,the 

### control module 

### will send 

### a reigntion signal to the 

### ignitor to 

### relight the 

### cooktop burner.**800~** 

### module. The first value, 2, represents the number ofmanual spark ignitors :while the second value, 

### 0, represents the number of reignition circuits. Reigntion circuits are not needed as the user has visual recognition of when the burners are ignited. High-end (i.e•• more expensive) gas range cooktops willuse ignition systemsutilizing a 0+4 controlmodu.le. Asjustdescribed, the first value. 0, represents the number ofmanual spark ignitors while the second value. 4, represents the number of spark ignitors with reignition circuits. Thus. 

### if 

### any of the gas cooktop burners become extinguished, the control module 

### will send a reigntion signal to the ignitor to relight the cooktop burner.

3

'1Na'I 

### ova: 9669 98t olS XVd 9S:0I OHM**66!ZI!~O**