Help choosing primary control for Beckett AFG Burner

[JamesW1984]

I have a Longwood Wood/Oil Furnace. I just bought a brand new Beckett AFG oil burner w/ the clean cut fuel pump. I thought the unit would come w/ the primary control, but it didn't, so now I gotta buy one. I've been digging online and looking at different ones. I read that the clean-cut fuel pumps have to have the pre-purge feature. I've been looking at the Honeywell Primary Control Units: R7184A 1026 ($113), R7184B 1024 ($127), R7184U 1004 ($159), and the R7184P 1094 ($139).

Here is an address to a comparison on the honeywell site: http://customer.honeywell.com/Honey...s/Catalog/SearchResults.aspx?multiselect=true

Also can someone help me understand the difference between interrupted and intermittent? I'm nearly positive I want an interrupted unit, but I'd like to better understand the differences just out of curiosity.

I've gotten the burner set up and adjusted. Literally, all I need is the primary control, hook it up, tighten a few bolts and I should be ready to purge the air.

I asked this question in a different forum and a guy replied suggesting that the units I mentioned above all basically do the same thing, but are worlds apart in what they're used for; I don't understand that. If they all do the same thing, why are they used for different things? Can someone explain?

 

[Sleepy]

It has been 10 years since I was a full-time oil burner tech, so take this as opinion, please.
A clean-cut pump simply has a 110 volt solenoid valve built in that is in the nozzle line outlet. All oil burner pumps have an adjustable pressure regulator the maintains 100+ lbs pressure to the nozzle. This pressure is required for good atomization of the oil. If the pressure is below 100 lbs. the oil droplets in the spray will be larger resulting in less complete combustion. This regulator normal stops fuel flow when the pressure drops to around 80 lbs after the motor shuts down. This means a little bit of poor combustion at the end of each cycle. With the solenoid, the pressure goes to zero instantly. This is why they call it "clean cut-off". The solenoid is also handy for adding a post purge cycle. The burner motor and pump can run without oil flow to the nozzle. After a short time, good airflow is established, the solenoid is energized, and the burner lights. Prepurge may be advantageous, especially in an oil burner that is direct-vented, but is usually not necessary in a older unit connected to a chimney. Any primary control should work well in a Logwood.

Interrupted vs intermittant: Interrupted means that the igniter will be shut down after flame is sensed. Intermittant means that the ignitor is on as long as the burner is firing and only shuts off when the burner is off. Interrupted ignition will require an primary control with a dedicated wire for the ignitor. With intermittant, the ignitor is wired with the motor.

 

[BrownianHeatingTech]

Prepurge and post-purge are nice, but not strictly necessary. Prepurge with a cleancut pump will give cleaner light-off, for the same reasons that were already discussed - the oil doesn't flow until it is up to the proper pressure. Postpurge helps to clear the last bit of combustion gasses out of the boiler before they have a chance to condense and cause corrosion, or back-flow into the house and cause odor.

Interrupted ignition is a bonus in terms of saving energy, extending the life of the igniter, and reducing radio-frequency interference from the igniter.

Make sure that you have a CAD cell, as well - if the primary control was not included, the CAD cell might not have been, either.

Lastly, in order to fire up the burner safely, you need a "T" or "Z" gauge to set the electrode position and nozzle headspace, a pump pressure gauge, to adjust the pressure for proper atomization in your combustion chamber, and a combustion analyzer to adjust the airflow for clean, safe, and efficient combustion. If you don't have those things, hire a local oil service company to do a set-up of the burner. Ask what they will charge to do that, "and by the way, what do you expect to be charging for cleanings, next year?" so they expect to have you as a service customer and give you a decent price on the set-up.

Joe

 

[JamesW1984]

I've been trying to find the part number for the correct cad cell for my r7184 Honeywell primary control. I've actually spent about 4 hours or more searching the net and I can't find a part number. The only cad cell (flame detector) listed on the honeywell site is the c554a1463, which doesn't list the 7184 as a compatible unit; can there really be that much difference? I've found several online companies who sell the c554a1463 - only one lists it being compatible w/ the r7184. I need to get this thing so I can get my burner set up. It's now been pushed back ANOTHER week.

I'm thinking I might call honeywell tomorrow and see what they have to say, but if someone else knows, throw your advice my way.

Thanks

 

[BrownianHeatingTech]

I've been trying to find the part number for the correct cad cell for my r7184 Honeywell primary control. I've actually spent about 4 hours or more searching the net and I can't find a part number. The only cad cell (flame detector) listed on the honeywell site is the c554a1463, which doesn't list the 7184 as a compatible unit; can there really be that much difference? I've found several online companies who sell the c554a1463 - only one lists it being compatible w/ the r7184. I need to get this thing so I can get my burner set up. It's now been pushed back ANOTHER week.

I'm thinking I might call honeywell tomorrow and see what they have to say, but if someone else knows, throw your advice my way.

The 7184 primaries use a spade connector on the underside of the box, as opposed to the older screw-clamp connectors that the 8184 controls used, so the compatibility has to do with the connector on the CAD cell's wires not matching.

If you get the 7184U primary, it comes with some short wires with spade terminals attached, which you can attach to the control, and then wire-nut to your CAD cell and other components.

Or you can get some crimp-on spade connectors of the appropriate size, and connect it that way.

Joe

 

[heaterman]

???????????

Just where exactly did you get your burner from? I don't know of a single supplier I deal with that would sell an incomplete burner. The primary control is an integral piece and as such is always sold as part of the unit. Go back to where you got the burner from and ask them for the right primary control as it should have been included with any new burner. If they sold you the burner without it, you probably got ripped off. Something ain't right here.

BTW, Joe is absolutely correct on the procedure to correctly set up and install the burner. There is no such thing as being "factory set" when it comes to oil burners. They have to be dialed in by someone with the proper knowledge, equipment and toolls to do it right. I'll guarantee that failure to do so will result in a mess that is beyond belief. Think gobs of soot hanging inside your equipment, burner heads eroded by flame impingement, soot covered walls.............all that happy stuff.

Do it once, do it right.

 

[JamesW1984]

I bought the burner online...probably the reason it didn't come w/ a primary control. I assumed it was a one-package deal as well, but when I checked on the website after receiving the burner, it didn't say anything about a primary control....that's how they offer it so cheap.

I typed a reply to Joe before, but apparently didn't hit the reply button to send it...here it is:

I live in Marshfield, Missouri (right outside of Springfield). There's not a large following of oil burners here, thus specialists in the field are few and far between. I originally literally got out the phone book and just started calling heating people in the yellow pages and none of them knew anything about an oil burner except for one guy, who is actually in my city. I had him come out and look at it and we replaced the fuel pump on my old set up; actually he helped me get it from a supplier, and I installed it myself to save some labor costs. Either way, that wasn't my problem. I thought for around 2 months about just getting a new furnace setup, but I don't really have the money to do so. I contacted my heating guy again and he said that getting my current furnace working would probably be the smartest option. He was fine w/ me purchasing the new setup myself and installing it. I read online in different forums and websites that oil burners need to be calibrated w/ the special equipment, etc, so I called him back and asked him if he knew anyone who could do it. He said that the only people he knows who can do it are in Kansas City and St. Louis...both 3+ hours away. I asked him to call them and see if they could do the calibrations for me; he called him and they told him that it would be a very large service charge to come all the way down here to do it for me. I asked him if it would be worth it and he said probably not. He said that he could come and set the pressure for me, but he doesn't have the expensive tools to calibrate it. I know I'm no expert, but I have read quite a bit about this stuff and I've taken mine all apart.

I've got the head and the new nozzles I bought for my old burner(which was the same style). I bought a pressure gauge that I'll use to set the pressure. I'm sure it would run more efficiently if it was professionally calibrated, but is it really gonna blow up and bust my furnace open and throw soot all over my walls? It's in the garage anyway, so I'll pull the vehicles out, just in case.

I don't really see an option here....there's NO ONE around who can set this up for me professionally. I either shell out $4-5000 for a new furnace, freeze next winter AGAIN, or I try to set this thing up myself. I know experts know more than me, but I've learned to work on computers and cars with the help of online forums full of helpful people such as this one. Any advice is appreciated, but I don't see having a professional set this up as being an option anymore.

 

[heaterman]

Ahhhhhhh yeeeeeeess. The internet has brought new and profound meaning to the term "Caveat Emptor", or let the buyer beware in plain English.

I don't know where you are in relation to "Hot Rod" Rohr (handle is HR here) but he lives in Missouri. If he can't help you out I'm betting he knows someone who can. He posts a fair amount here and If you can get him to lend a hand you'll be in the care of one of the best heating guys in the nation let alone Missouri. His specialty is piping and all things solar and hydronic but I know he's run across more than a few oil burners.

You might post your dilemma over at www.heatinghelp.com and see if someone in your locale pops up there. A lot of the best in the industry hang out there.

AFA the 7184 goes, the one you need should be the R7184A1024 which has a 15 second pre-purge or valve on delay. It would be the one I'd recommend as the valve delay gets the air moving through the burner and establishes a little draft before light off. It can make for a little smoother ignition in some equipment. The cad cell kit you want is a C554A1793 which comes with 1/4" spade connectors and multiple mounting brackets to fit about any burner and the 7184 listed above.

I have 'em both in stock and can stick 'em in UPS Monday if you want. Cost is $121.45 for the 7184 and $19.95 for the C554 plus around $10 for shipping. E-mail me at [email protected] if I can help.

On another note, if you can return the burner you have, I can get you a complete AFG for about $585.00............Just a thought...................I'd be willing to put it on the test stand in the shop and dial it in for you. I'd have to know what the recommended firing rate is for your furnace. All you would need to do would be to install it and make sure your chimney draft is between .02 -.04" W.C. negative. Over the fire draft is something you could find out by calling the manufacturer of your furnace and that would of course have to be set on your equipment.

As with most things in life, it's what you don't know about something that will jump up and bite you in the butt. I've learned with heating equipment that there is almost ALWAYS more involved than meets the eye. It's not just parts and pipe. All these things are designed to work as a system, in their proper sequence and under a certain set of parameters or conditions. Hope this helps.

 

[JamesW1984]

Contacted "Hot Rod" and here was his reply:

"Hi James

I'm not well versed on oil burners either. I've not found anyone locally that has much experience. Oil burners are a rare breed around here. Sorry

maybe some of the commercial heating contractors in Springfield?

Bob"

The manufacturer of my furnace (Longwood - NOT LOGWOOD) is no longer in business. Honestly, I'm simply replacing one burner w/ another and using the same nozzles. If I get the pressure dialed in and have the electrodes set properly, I think I'll be fine. We'll see...my CAD Cell and Z Gauge should be here this weekend and I'll get started.

Thanks for the help

 

[BrownianHeatingTech]

Honestly, I'm simply replacing one burner w/ another and using the same nozzles. If I get the pressure dialed in and have the electrodes set properly, I think I'll be fine. We'll see...my CAD Cell and Z Gauge should be here this weekend and I'll get started.

Do you have the right combustion head on the burner?

Correct nozzle (flow rate, spray angle, and pattern)?

Joe

 

[JamesW1984]

Using the same F head as well, which is applicable to the AFG. I've compared it to pictures on the Beckett website and I'm pretty sure mine's the F0 head. My heating guy got new nozzles for me from a supply house for my old Beckett burner. The guy at the supply house matched them up to the older ones for the older burner. I'd assume it would be the same since my new burner is a Beckett, and the flow rate and everything should match up once the pressure is dialed in, right? I think the pressure was set to 140 psi from the factory. My nozzles are rated at .75 gal/hr at 100 psi, so that's roughly .83 gal/hr at 140 psi. The nozzle angle is 60 degrees, which the manual recommends 70 or 80 degrees, but I guess I'll do some trial and error there. If I need a wider angle, I can always get a new nozzle. I'll probably back the pressure down to 100 psi since I don't really need .83 gal/hr (116,000 btu).

 

[BrownianHeatingTech]

Using the same F head as well, which is applicable to the AFG. I've compared it to pictures on the Beckett website and I'm pretty sure mine's the F0 head.

The number should be stamped into the face of the head. May need to clean it to read it. Make sure, because the head is a biggie...

My heating guy got new nozzles for me from a supply house for my old Beckett burner. The guy at the supply house matched them up to the older ones for the older burner. I'd assume it would be the same since my new burner is a Beckett, and the flow rate and everything should match up once the pressure is dialed in, right? I think the pressure was set to 140 psi from the factory. My nozzles are rated at .75 gal/hr at 100 psi, so that's roughly .83 gal/hr at 140 psi. The nozzle angle is 60 degrees, which the manual recommends 70 or 80 degrees, but I guess I'll do some trial and error there. If I need a wider angle, I can always get a new nozzle. I'll probably back the pressure down to 100 psi since I don't really need .83 gal/hr (116,000 btu).

Make sure not to go below 100 psi. Pressure is very important for proper atomization. Going to a .65 nozzle and keeping the pressure up will give you a cleaner burn.

However, even once you get the head, nozzle, and electrodes set correctly, you'll still need to set the air band and shutter, and that requires a combustion analyzer.

Joe

 

[heaterman]

I would second what Joe says about leaving the pump pressure alone. You'll get a cleaner burn, all other things being equal, with the 140 PSI setting due to better fuel atomization. Various firing rates for nozzles of different sizes @ 140 PSI are as follows:
.65 = .77gph
.75 = .89gph
.85 = 1.01 gph

The other thing to consider is that if you furnace is designed for a certain firing rate, it may be damaged by dropping too far below it. The reason for this is the manufacturer (should have at least) experimented with various firing rates to achieve best efficiency as well as the required flue gas temp tp avoid condensation. If your flue gas temp is too low (usually below 350* with oil) you will get condensation in the heat exchanger as well as the chimney. Both are very bad for the service life of the equipment involved. I've seen chimneys literally disintegrate in a matter of a couple years due to low flue gas temps. Chimneys, last I checked were not cheap so do your homework and test the flue gas temp after you get fired up.

Also remember that actual BTU output for #2 fuel oil is 139,000 x the efficiency of the appliance which in you case is probably about 75% at best. That's the actual number you're looking at for heat available to your house.

 

[JamesW1984]

Ha ha ha, sounds about right. My Z gauge came in, but my CAD sensor didn't. It was supposed to be here yesterday, but I checked the UPS tracking system online and it said it was out for delivery, but then later on it said "Emercency Conditions beyond UPS' control." I thought they ran on Saturday, but it says scheduled delivery is for Monday. I guess I can still get it all wired up, bleed the lines, and get the electrodes set correctly w/ the Z gauge. All I'll have to do Monday is hopefully throw in the CAD sensor.

I don't know if I've mentioned this before, but the oil burner is just primarily to get the wood started burning. I don't plan to burn oil except for starting up the furnace. The oil should start the wood burning so I don't have to manually, which then will allow me to control the heat in the house w/ the thermostat. As long as I have wood in there, it should burn the wood. Now that I'm thinking about it more, I'm not 100% sure how the burner knows when to shut off after the wood starts burning. I know the back of the furnace has a sensor that kicks a fan off an on to help burn the wood; I always assumed that sensor is what let the burner know to turn off.

By the way, I've confirmed that my head is a F0. Thanks for telling about the stamp on the face of the head, Joe.

Thanks, guys.

Oh, heaterman, yeah, after figuring in the efficiency of the furnace, I probably should just stick w/ the .75 nozzle at 140 psi. That should net me about 92000 BTU's at 75% efficiency (not real sure what the real efficiency is).

 

[JamesW1984]

Alright guys, got the CAD sensor in today and got everything wired up. I set the electrodes and nozzle position w/ the Z gauge over the weekend, so that was already done. I bled the lines for about 12 min (set the primary control into bleed mode so it would stay on for 4 min and I did 3 times)...the lines seem to be pretty good. It'll run clear and then every once in a while it would shoot some suds through. I might try to bleed it some more later on if that seems to be a problem.

I did have the issue where the whole furnace filled w/ smoke and all of that, but it wasn't as bad as I figured it would be. After that got done, it's really not that bad, just out of adjustment still. I've moved the air shutter to every position from 0-10 while the burner was running. My furnace is such that you can keep the door open an inch or so without it tripping the safety, so I can see the flame in there to diagnose what issues are occurring. That being said, I can't seem to get it adjusted to keep oil from pooling up in the furnace. It doesn't have massive amounts, but definitely too much if it's dripping from the burner hole. It seems like maybe it's not dripping when I move the shutter to around the 10 position, but the flame goes out if I have it in the 10 position very long.

I know you need instruments to properly set this stuff up, but aren't there some rules of thumb that someone could go by? One other thing, my nozzle is a 60 degree .75 nozzle and the flame shoots out of the retention head a good 12-16 inches. I thought with the wider angles, you were supposed to get shorter flame?

I guess I'll play w/ it some more and try to get the excess oil problem figured out. If I drop my pressure, would that help? I haven't set the pressure yet (from the factory, it's supposed to be 140, which is what I was planning on leaving it at.) I need to make sure I'm done bleeding it and get my gauge on there. I'd rather not play w/ the pressure unless I need to...keep as many variables out of this situation as I can. However, I guess w/ the gauge, I could always set it back to where it was.

 

[heaterman]

Leave the pressure alone. It's fine where it is and doubt if it's the problem.

Does the flame seem to "float" off the burner head? In other words, is there a noticeable gap between the head and the flame?

If you have oil pooling in the combustion chamber somethings not right with the distance between the nozzle and the head. That dimension is probably the most critical adjustment after the air setting.

Your AFG has two air adjustments, one is the ring with the pointer on it, which I think you're referring to and the other is the roughly 1" wide band alongside the air ring. Start with the band closed all the way and the air ring somewhere between the 7 and 9 position. That should get you close IF your draft is where it should be. You want about -.02 WC " draft for oil ( and that's one of the major problems with a wood/oil combo as you need more than that for wood) If the draft is there, and the air setting is right you'll see a nice clean flame with pointed tips. If you're seeing "sparks" out past the flame and it's a brilliant yellow/white you have too much air. If the flame looks lazy, sooty or smoky and is a medium to dull orange, you don't have enough. You want a nice bright yellow/orange colored flame.

What are the physical dimensions of the interior of the combustion chamber? A 60* nozzle would be used in a firebox that is longer rather than wider.

I know it's frustrating but the rule of thumb with any heating equipment is to do it right. In your case that would involve a combustion test and burner setup by a tech familiar with oil equipment. Just be careful , you're playing with something that can create a ton of CO in a hurry along with really messing up your day in any number of other ways.

 

[JamesW1984]

I adjusted it some more tonight...spent about an hour and a half moving the air adjustments around and watching the flame. Before I did anything, I pulled the electrodes out and used the Z gauge to check them (they're good) and adjusted the nozzle to head a little bit...it seemed to be up about 1/8" too far, so I did that. Then, I started it up. It was still dripping oil out of the hole, so I don't really know what to do about that. Really, I moved the air ring (shutter?) around trying to get it where it wouldn't drip oil. I then started moving the air band (1" band) around. I could be wrong, but it seems to me that w/ the air band opened up all of the way, and the shutter on about 6, it fires pretty good. It seems to not drip as much, maybe even stop dripping at that point...it's hard to tell since I can only see through the door about 2 inches at an angle because of the safety feature (probably a good thing it's on there).

I'm gonna search the net a little bit and see if I can find some pictures of what exactly a good flame is supposed to look like. What I have looks good to me, but then again, I really don't know what a good one looks like. Mine looks to be about 4-5 inches in diameter, shoots out about 12-16 inches, and I'd say it's maybe 70% yellow, 20% orange, 10% white...I can't really explain it. It's not real bright orange, mostly yellow.

Oh...my LONGWOOD firebox is a 16" diameter cylinder and 54" long. The burner is placed in the front right corner. The door measures 12" wide by 11" high.

Is there anything else that could cause it to drip oil besides the nozzle-to-head length? I set that w/ the Z gauge and it hasn't fixed anything. I put the Z gauge on over the nozzle and pushed it down snugly and the inserted the electrode unit w/ nozzle into the air tube and pushed it all the way up to where the z gauge was touching the little inward fins on the head. I adjusted the echelon (spelling?) plate and pulled it back out, removed the Z gauge, and replaced it all.

Thanks so much for the help.

 

[marleyq78]

Do yourself a favor, if you want to play oil man buy your self a wet kit. i found this one on ebay

http://cgi.ebay.com/Bacharach-Fyrit...ryZ41987QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

- set the burner up first by getting a trace of smoke then bring it down to 0 smoke-
- then take co2 readings(10.5%-12%)
-draft (preferable around -.04" )
ps.- AFG w/ f-heads usually run best with a 70 or 80 degree nozzle. 60 degree has a tendency to carbon the endcone
Do you have the model # of the furnace I might be able to look up the correct nozzle.
If not post the demensions of the chamber I could look up to see what nozzle would possible work.


jr76

 

[JamesW1984]

I posted my chamber size in the previous post: The chamber is basically a 54" long cylinder that's 16" in diameter. I've thought about buying the testing equipment, but I'd rather not if I can help it. I'll watch ebay and see if I can find a good setup. Winter is almost over, so I really have until next winter to get this thing set up. I bet I can find some good used gear on ebay now that the winter season is almost over. I could give you the model number of my furnace, but they don't make 'em anymore and probably not many have heard of it. It's a LONGWOOD (not Logwood). They were made for about 20 years here in Missouri; they stopped making them about 10 years ago. The man who designed it died and his family sold parts for a while, but they quit selling parts in 2005.

 

[marleyq78]

Longwood Furnace Co. --lw101--f3 head-- .85/60B nozzle-- pump presure 100psi --approximate air setting- air band 7/air shutter 0

sounds like your problem is that you need an f3 head--
f0- is only good up to .75 gallons- yes i know thats the size of the nozzle your using, but your at the maximun firing rate of an f0 head-

my suggestion is to get f3 head and buy the wet kit--
your playing with an unattended fire inside your house--very dangerous-- just some advised

 

[JamesW1984]

I guess I'll stop being a hard head and get some equipment. I got until next winter to get this thing set up right. I'll assume the older equipment will work fine and I won't need the newer electronic stuff. I'll do some research on that. Thanks for all of the help guys.