Intermatic C8835/ Honeywell RA89A Relay Wiring Problem

blacklab11 · Post by **blacklab11** » Sun. Sep. 28, 2014 7:44 am

Greetings, I have a EFM520 Coal furnace. I am replacing a Honeywell R883 timer/relay unit on this unit with an Intermatic C8835 and a Honeywell RA89A relay. Can anyone help with the proper wiring of these new parts vs. the old Honeywell R883. I have low and high temp aquastats that are Honeywell. I have wired these new parts and can get the stoker motor to function but not in a call for heat situation to recover water temp. I have the inline power to the C8835 timer and power then to the RA89A relay and out the relay to the stoker motor and that works. WHAT WIRES DO I NEED TO CONNECT TO THE "TT" TERMINALS ON THE RA89A RELAY SO THAT THE FIRE IS MAINTAINED AND THE STOKER MOTOR STARTS ALSO IN A CALL FOR HEAT SITUATION??????? What might I be doing wrong??????? Thanks so very much.

ntp71 · Post by **ntp71** » Sun. Sep. 28, 2014 7:56 am

pm glenn harris ... he should know

McGiever · Post by **McGiever** » Sun. Sep. 28, 2014 7:59 am

So, the timer part works as expected...just that the boiler never recovers from a heat call?

TT should be signal from aquastat that boiler water temp is below setpoint. Open/Close signal...Just a Dry Contact...no power needs sent.
You may test this by touching a jumper wire across the TT points.

Post by **Rob R.** » Sun. Sep. 28, 2014 8:25 am

Is this a steam system? Normally that is what the R883 would be used for, and the thermostat would be connected to the TT terminals. If this is a hot water system, I would wire it differently. Explain how the entire system is wired/setup.

blacklab11 · Post by **blacklab11** » Sun. Sep. 28, 2014 10:23 am

My system is Hot Water. Presently my low temp aquastat is on the "TT" terminals. If I jump the "TT" terminals on the RA89A with the C8835 the stoker motor starts and will run until the timer setting expires. I connected the old Honeywell R883 again and everything works, however I need to change the old unit out as it is not reliable. When it is wired correctly the stoker runs every 1/2 hour to maintain the fire. When I hooked up the new C8835/ RA89A it will not run to maintain unless I manually jump the "TT" terminals. On my new setup should the thermostat wires be on the "TT" terminals or the aquastat. Again I can not put my finger on what I am doing wrong. It is probably so simple. Thanks Much for Helping

McGiever · Post by **McGiever** » Sun. Sep. 28, 2014 10:46 am

Leave t'stat at L8124 "TT" terminals.

You need to parallel feed the stoker/burner motor.
At the L8124 take 120volts from "B-B1" to stoker/burner...and at same time, get switched/cycled 120volt from C8835 timer to stoker/burner...2 different sorces...1 motor.
An easy way to parallel is to make a splice in a junction box nearer to both the timer and to the L8124 using wire nuts...then you only need to run the combined single 120volt any distance.

Obviously the old [all-in-one] RB-883 did this paralleling internally.

blacklab11 · Post by **blacklab11** » Sun. Sep. 28, 2014 10:50 am

Mc Giever, Thanks. I should have stated that I have seperate LOW (L444B) and HIGH (L4006A) temp aquastats. Can I use a L8124 on a coal unit???? Thanks Much

McGiever · Post by **McGiever** » Sun. Sep. 28, 2014 11:02 am

Sorry for mix up, was another poster w/ L8124.

Yes, can use L8124, or L7224 is even better. There are variations of these, so be sure which one you want/need.

blacklab11 · Post by **blacklab11** » Sun. Sep. 28, 2014 11:14 am

McGiever, Can the C8835/RA89A be used with my present aquastats??????

blacklab11 · Post by **blacklab11** » Sun. Sep. 28, 2014 11:19 am

MCGiever, If so what wires go on the new RA89A relay "TT" terminals to trip it to work????????

McGiever · Post by **McGiever** » Sun. Sep. 28, 2014 11:25 am

Yes, "TT" in RA89A...but is stoker motor already paralleled also?

Cause now 2 separate devices need to start 1 motor.

blacklab11 · Post by **blacklab11** » Sun. Sep. 28, 2014 11:33 am

This is probably where I am messed up. What does it mean PARALLELED??????

blacklab11 · Post by **blacklab11** » Sun. Sep. 28, 2014 11:36 am

The motor will start if I manually jump the RA89A relay "TT" terminals. So I must have something missing regarding what is needed to make this new setup trip. Perhaps the old R883 did this internally. Thanks

blacklab11 · Post by **blacklab11** » Sun. Sep. 28, 2014 11:38 am

McGiever, Thank You for your patience

McGiever · Post by **McGiever** » Sun. Sep. 28, 2014 12:36 pm

blacklab11 wrote:The motor will start if I manually jump the RA89A relay "TT" terminals. So I must have something missing regarding what is needed to make this new setup trip. Perhaps the old R883 did this internally. Thanks

Manually jumping the "TT" is a simulation of the thermostat calling for heat...when satisfied it's off until the next call comes. Period.

As for the timer, it needs to call for a cycled run-time independent of when the thermostat calls. You see this is 2 devices now, where before it was all in only one device.

At your L440B aquastat install a permanent (short) jumper from the same connection that now has the wire leading out to stoker motor is on... over to the unused connection opposite of it...now it is paralleled.

Report back your results, please.