Furnace playing games
Hello,
New here, and hoping for some help. Any/all will be appreciated.
I have a "new out of the box" (older system). Armstrong horizontal mount forced air w/Beckett oil burner. I'm pretty familiar with the system and have done the research to feel confident servicing it myself. Seems all techs around here are young and do not know anything about this furnace.
Problem…Everything works fine for a day, days, weeks, then all starts playing a mind game. Most the time will reach set temp, but then there's times where it seems to short cycle getting farther and farther away from set temp.. If I turn breaker off (cut power to unit), then turn back on, most of the time, it will cycle. Again, maybe reaching temp., maybe not. Temp set at 68, this morning wouldn't get above 60. Now set at 70, and holding strong (after doing nothing but turning breaker off and on). Recent issue, that seemed to have started this was, dead birds in exhaust flue. Cleaned everything, vacuumed, and fought the "short cycle" for long enough to check everything. Electrodes, CAD eye, limit switch, nozzle, filters, etc.. While reaching for a tool, brushed the reset switch, which wasn't poped, and suddenly all started working as should. Messed around with the switch some, and all was working well for a week+. Now Im back to, sometimes runs fine and holds temp., sometimes not. Does run and keep some heat when acting up, but will not reach temp.. For an unknown reason, seems to love holding 70, but not lower setting. Also, have a new thermostat that I installed while trying to troubleshoot issue. Flame looks nice, and all runs perfect as the burn goes, just have this issue with sometimes holds temp., sometimes not.
Im now thinking the issue may be in the ignition primary. One on unit is a R8184 G 1032, which appears to be "old school". I do have a new R7284U, which I believe will work. If this may be the issue, I can swap out, but just slightly on the novice side of the settings that can be made with this newer primary.
Would greatly appreciate any input. Thank you.
Comments
-
You are focused on the room temperature. The focus needs to be on the burner.
When the room won't reach temperature, do you go down and observe the furnace? Is it running or has the primary shut it down? If it is the primary, you'd need to press the reset button on the primary, at which point it would immediately start. You would then observe it for at least 10 minutes to see if it will continue to run or shut down again due to the primary.
The above is necessary before we can go further.
The R7284U is a much better unit than the R8184 (which is probably original).
0 -
Check you wiring. Check your neutrals. Check all the wire nuts. Sounds like a wiring issue to me.
Miss Hall's School service mechanic, greenhouse manager, teacher, dog walker and designated driver
0 -
I have not had to press the reset at all during any of these "act ups". It has not popped. I only mentioned that as I just slightly brushed it at one point and seemed to make all work fine. Almost as brushing is just wiggled it enough to make a needed contact…???
Yes, I can control power to furnace while in basement working on it. So, yes, there when it starts up and runs. All seems good with a clean burn.
I am focused on both, as I do want room temp., while trying to figure out why unit dosent run long enough (at times) to achieve this.
This is an old furnace, but taken out of box as new just 3 years ago. I needed to replace my old, and found someone with the same unit sitting in back of his warehouse. Simple plug and play as that went. R8184 is original.
0 -
sorry, furnace does shut down prior to reaching temp..
0 -
I agree with Grallert. You have a wiring problem and something is loose. Take off the R8184 and rewire it from scratch with all new connections. Or, install the 7284U since you have it doing nothing. The problem is not likely to be the R8184 itself but you never know.
If the 8184 did NOT shutdown on safety, you have eliminated all combustion issues that might have been present.
0 -
LRCCBJ - unit will cycle again on its own, but temp on thermostat is way below the temp calling for heat. Shuts down as what I would almost think as an "overheat" in normal situations. Kind of like a short cycle. Nothing pops as a reset would go.
Grallert - Yes, this is my next mission prior to changing primary. I've done a "quick" look, but not through.
Changing the primary seems simple enough, Im just hesitant on the settings that can be made during set-up. The delay times.
Thank you both!!
0 -
Electrical issues can always be "mind blowing" especially with automotive. Im just baffled as to why a hard time keeping at least 60 this morning (as with other times) while thermostat set at 68. This was from 4-5:30 AM. then set thermostat to 70, breaker turned off and on, and has held 70 since.
I appreciate you both taking some time to respond. HAHA…Ive been on the verge of thinking I was loosing my mind.
0 -
Seriously, if the furnace shuts down, it cannot bring the house up to 70°F. Nothing baffling about that.
The issue is simply why the furnace randomly shuts down. That's usually wiring, unless the 'stat is defective………….and you already ruled that out.
You want to talk about baffling……………changing a ceiling fixture in an old house…………..disconnect the line from the switch………….and shock myself with the opposite line. How's that possible? Well, when you switch the neutral…………that's what you get!!
1 -
The R8184G could have bad contacts. If it wasn't in safety, but just lightly tapping it by coincidence started the burner, I'd say that's likely the case.
The R7284U is an easy upgrade. Just make sure you program it for no pre or post purge if there's no oil delay valve.
And FYI, oil burner service is not DIY. "The flame looks good" doesn't cut it.
4 -
HVACNUT- I fully understand this is not DIY. My old oil guy was from a family ran business and an old timer who knew these older systems. Ran with basic tools and kept things running. They/he closed the doors years ago, and area took over by a more "commercial" type company with all younger (id guess in 20's) techs. I got tired of paying for multiple visits and problem not solved until 3 or more visits/bills. So doing research, both Beckett and Honeywell have alot of great info to read, and I did ALOT of reading. Yes, you need some basic concept to start, but there is alot of great information out there. My grandfather was also in HVCC, and did learn alot of "old school" from him. Today, and todays systems are ALOT different is some ways. All have basic things to check, besides flame. Draft, smoke, correct Ohms, and flue heat to check to be sure a furnace is running correctly and efficiently. All somewhat specialized tools to do so, with knowledge to use them. With my system, everything is well within the parameters to look for, just not mentioned. The only thing I didnt check was smoke.
I would NOT recommend anyone going at there system DIY without any knowledge. You Tube videos dont cut it. Some are good, but also have alot of not so good ones. Make you know enough to be dangerous.
In my case, system was running fine all day with thermo set at 70. kept house between 69 - 71 all day. At a point, I shut system down and went through wiring. Didnt see anything that fully stuck out as an obvious problem. Re-did all connections using dielectric grease. All is running again, at this time. We will see if it all stays good or not. If nogo after some time, I will opt to change primary. Every time I have done something, all will run fine for quite a few cycles, but eventually get to the point that wouldn't keep house heat up to temp set.
0 -
HVACNUT is on it. Replace the bad primary control.
0 -
All ran perfect all day, keeping house at 70. Of course issues arise when time to relax and sleep come.
I plan on making it through the night, and changing out primary 1st thing in daylight. My cellar access is out at back of house.
Im an "analog man", not keen on digital. "old school". Going with replacing the old R8184 with newer R7284 primary has left me with a few questions. I got wiring down pat, which has seemed to be an issue with few. I'm good there. Researching both furnace and burner, Im left with a couple…."I don't knows".
valve on delay - I believe 0
Ignition (lock out) time - 15 sec.?
Burner off delay - 0 ?
TT configured on - yes?
spark in on delay - no?
spark during run - yes, as following all I know for sure is the old primary is an intermittent system. I have seen yes, and no for this, but in my case going with yes.
Thanks in advance for any / all replies.
0 -
spark during run - yes, as following all I know for sure is the old primary is an intermittent system. I have seen yes, and no for this, but in my case going with yes.
You don't need to be wedded to the old control. It cannot smack you with any judgment during the divorce.😁
The 7284 can be run as interrupted. Why do you need the spark output after the burner fires? In fact, there are some arguments that the combustion is slightly improved without the spark sitting directly in front of the nozzle.
1 -
what really mess's with me is, it does run and heat. Will do so at demand from thermostat most of the time. As said, ran fine all day today. Now, I can almost guarantee, it will keep kicking on to keep house temp at 53 min., even though thermo set at 70. Haven't had ANY lock outs. I can seem to kick it on, from within the house, by turning breaker to it off and on. I really hope its all in the primary.
Worst part, and most mind baffling, is, every time I do something, system runs as should for a good amount of time. Acts up at worst times, usually night.
0 -
Would you please stop fretting about it……………..just move forward in a methodical way and eliminate it.
1 -
If valve on delay 0, burner off delay 0, as it should be without a delay oil valve, then "spark in on delay" correctly won't be an option. Spark during run, NO.
The hardest part for you is going to be getting all the wires in the junction box and tightening the screws without pinching the wires. Be careful here. They give you wire nuts and pigtails. Make good splices.
*Before you turn the power on, remove the cad cell eye from the burner. Close everything up and start it. Make sure the safety works and shuts off the burner within 15 seconds. Now pop the eye back in.
1
Categories
- All Categories
- 86.7K THE MAIN WALL
- 3.1K A-C, Heat Pumps & Refrigeration
- 55 Biomass
- 423 Carbon Monoxide Awareness
- 102 Chimneys & Flues
- 2K Domestic Hot Water
- 5.6K Gas Heating
- 102 Geothermal
- 158 Indoor-Air Quality
- 3.5K Oil Heating
- 68 Pipe Deterioration
- 935 Plumbing
- 6.2K Radiant Heating
- 384 Solar
- 15.3K Strictly Steam
- 3.4K Thermostats and Controls
- 54 Water Quality
- 43 Industry Classes
- 47 Job Opportunities
- 17 Recall Announcements