View Full Version : RM7895 BURNER CONTROL PROBLEMS
01-17-2010, 11:17 AM
I'VE GOT ONE ON ORDER FOR A MUA UNIT, THE PROBLEM WAS THAT IT WOULD NOT INITIATE HEAT OPERATION WITH A CONSTANT 115V TO TERM. 5 AND 7 , TERM. 7 IS A INTERLOCK FOR YOUR LIMITS, AIRFLOW ETC. , PRETTY STRAIGHT FORWARD, I NOTICED AFTER ABOUT 2MIN.S OF POWER TO CONTROLLER THAT THE GREEN LED POWER LIGHT WOULD SLOWLY DIM AWAY, ANYONE EVER SEE THAT?
Do you have a 7800 Display plugged in to see what is going on? You can enter into diagnostics and see if the burner control is seeing all the input signals. I seem to remember the greed LED going on/off in standby.
01-17-2010, 03:43 PM
green light stays on during stand by. Has this controller been in opperation for awhile?
01-17-2010, 03:52 PM
not too long maybe 7 yrs. , yeah that light should stay on as long as there's power to it
Check out page 8 under Safety Provisions, Internal Hardware Monitoring. Addtionally I believe you need power to terminals 5 and 6 to initiate an ignition cycle, terminal 6 is the operating / limits and terminal 7 is the Air proving switch (of course sometimes they're jumped together depending on the control arrangement).
01-18-2010, 07:15 PM
thanks for the info., yeah they were jumpered
01-18-2010, 07:25 PM
that article says it blinks every 4 sec.s, the power led would just go completely out though, replaced the controller today and unit is up and runnin, the rm7800 series have always been so reliable, shoot i think this is my second in 10 yrs. so i just have a hard time replacing one
I have to agree with you there, I've seen my share of 7800's and rarely have I lost one due to an internal issue. I have a couple on oversized boilers that reached 99,999 cycles 2 years ago and just keep on going. Glad you figured it out. I don't know if have one, but the display window is the handiest tool for troubleshooting problems when they do occur.
I find the Honeywell 7800 series the most reliable primaries. It would be a cool discussion to find out what everyone thought were the most problematic primaries.
I would say Fireye TFM-2.
01-18-2010, 08:52 PM
I had 3 of them last year that was bad on start up. other than that they are hard to beat.
01-19-2010, 07:50 PM
totally agree with you ascj
Powered by vBulletin® Version 4.2.0 Copyright © 2013 vBulletin Solutions, Inc. All rights reserved.