Honeywell random fault lockout

NYCLandlord

Honeywell random fault lockoutThis summer, we converted to gas from oil with a Smith cast iron 5 section HE steam boiler using Powerflame controlled by a Honeywell RM7897A1002 burner control to provide heat and hot water for a 5 story 20 unit building.  Anyone in NYC will know that getting a deciated new gas line service can take 6-12 months.  We applied for the serivce and replace the boiler in May and still do not have a deciated gas service, instead, as an only alterntive, two gas lines from residential meters feed the gas steam boiler.  It was working great during the summer, but we are getting more and more random fault lock-outs from the burner control.

Nov 7: fault code 28 "pilot fault error"

Nov 19: fault code 127 "internal fault"

Dec 10: fault code 1 "purge card fault"

Dec 13 ; fault code 127 "internal fault"

All during the PRE-PURGE cycle.  After a reset, things seem to run normal.  A boiler technician friend seems to think that random faults are due to possible gas surges or drops(still inadequate pressure during high demand),  and to tell the boiler installer to adjust the gas valve on the boiler. 

While what he says make sense, would gas pressure issues cause these kinds of ramdom fault lock-outs?  I would expect to see some sort of fuel supply fault.  Any help would be appreciated.

SWEI

residential meters

Are paralleled on the low pressure side?  Are they 250 CFM?  19HE-5 fires up to 725 MBH - that's three of those meters, though the utility can run them at higher pressure and squeeze a bit more out of one.  Do you happen to know what the burner was setup for?

NYCLandlord

Honeywell burner control

I recall one meter was rated 250 and 80 on the other.  The label on the boiler had a max input of 722,000 btu/hr and a min input of 242,000 btu/hr.

The situation was either no heat at all, or run it at a lower flame.

The burner is new from manufacturer so I assume its probably set up for original specs.



Would this cause all sorts of fault errors?  Does the burner need adjusting to compensate for lower pressure, then back to facory specs once we get dedicated service?

SWEI

flow

330 CFH = 338,910 BTU/hr (assuming 1027 BTU/CF.)  More than this and the pressure will drop.  How much depends on the initial pressure the utility set the regulator for and the particulars of the meter.



You *might* be able to persuade the utility to turn the regulator up a bit if this is only feeding the one burner.  I wouldn't count on it, but it's probably worth asking.



You may be able to have the burner setup to fire at less than full rate, which (assuming the boiler was properly sized) would deliver less than optimal performance, but at least it's something.  What does the installer say?  Did they measure radiators before they decided what to install?

NYCLandlord

Lowering the pressure

I'm trying to figure out under what conditions would cause different faults. If its the lack of pressure, shouldn't it cause the same error consistantly? We also have two 75 gal high recovery water heaters on the same line used in the summer when the boiler's domestic hot water goes off-line. In an attempt to replicate a fault error, I turned them on then fired up the boiler. Everything ran normal. The decreased pressure did not affect the boilers operation.

JohnNY

Who installed this ?

Can't you get the installer to make this work?



There are no 80,000 BTU meters in NYC. The smallest ones I ever see are 250,000.



Pressures fluctuate with area and local demand.

NYCLandlord

not 80,000, 80

Two meters, one clearly marked 80 and the other marked 240 (or somewhere near 240).  I have a service apt with the installer, but I wanted to know if this could be the problem.  Not that I dont trust them, I just dont want to resolve this by trial and error.  I have understanding tenants when its 45 degrees outside, but they may not be so when its turns in the 20's.  Still waiting for Con Ed for establish a gas serice, I dont expect it until at least next year. 

I was hoping that someone here could confirm or have experienced that surging/dropping gas pressure could give off different fault codes in the PURGE stage.

JohnNY

I realize the meter doesn't say 80,000.

But if it's a class 240 meter, then it's a 240,000 BTU meter. Hence my 80,000 figure.



Good luck.

NYCLandlord

Smallest in the building

Oh, I see.  Sorry, forgot to do the conversion.

Of the 18 units, I think this is the smallest in the building, but definitely 80 CFH.  There was a sticker saying "last inspected 2006"



We were able to run the two hot water heaters (74 gal, 75,000btu each) just on this meter alone.  I guess water heaters dont care how much gas.... jsut as long as it gets gas. 

SWEI

do they have the capacity in their main?

On light commercial or large residential services out here they frequently drop the main to 5 PSI before the meter, then regulate down to 7" afterwards.  The meter capacity expands by a factor of 3 - 3.5x the nameplate as a result.

will smith_4

Lockouts

I would recommend having the flame safeguard bench tested to rule out programmer problems. Don't start trying to adjust gas pressure to the burner unless you have a combustion analyzer-assuming it was set up properly at start-up, if you change pressure you'll change how it's firing-if done improperly, you'll end up sooting up the burner-not good!

Common causes of pilot failures on Powerflame burners are incorrect pilot pressure, and too much air-usually caused by the dampers being open too much or air leakage around the burner. You can find the manual for your burner on their website.

I'd certainly recommend having your service co. get this resolved-not a do-it-yourself type of project...

tim smith

Re: lockouts on flame safeguard

Your varying errors concern me that you do not have a good ground to your flame safety. These electronics are very sensitive to proper grounding and stable voltage. Have someone check you voltage to burner while operating to see if you are getting fluctuation. Check neutral to ground for any voltage, should not be any. Verify solid ground from ground bar at panel to flame safety/burner.  Good luck.  T

RJ_4

gas press.

You need to maintain at least 6 inches w.c between the reg on the boiler and your parrallel regs.  while the burner is operating.  ( where the pilot piping is attached to the gas line )   7 inches would be better,  if you cant burner wont oper. properly.   have the Gas co. meet you at the job site

NYCLandlord

Dont think its gas, its probably electrical

I did some experiments over the weekend, and I tend to agree that it might be electrical, computer or a grounding issue. The boiler ran normal for two days while having the two hot water heaters on-line. If gas pressure for flux was an issue, it would most certainly trigger another fault.



Since I have the keyboard attachment that allows you to read the fault history, I think the pilot error was at the very beginning of the installation. It seems that in the last three months, I've had two internal fault, 1 purge card missing , and two "setup needed".



What makes me think that it could be the computer controller are the "setup needed" errors which requires a manual password to re-program. This only occurs at the very beginning of the initial installation configuration. This prepurge info is stored on units memory and unaffected by shut-down or restarting. So, I'm asking, what external factor would put the controller in the state where manual programming is required. I dont think there are any. I'm beginning to think it might be either a software or internal issue. Any ideas?