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BillyHvac, Journeyman HVAC Tech
Category: HVAC
Satisfied Customers: 22510
Experience:  Endorsed for unlimited heating, cooling, oil burners, boilers, refrigeration, hydronics
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I have a Rheem electric forced air heating system in my home.

Customer Question

I have a Rheem electric forced air heating system in my home. Today althopugh the thermostat is set at 62,it won't turn off. It just runs and runs and the house is much warmer than it shouldm be - clise to 80. First I shut off the main breaker for the whole hearter. I took off the panels and found 4 separate breakers. I turned on the main one at the Electric panel for the house and turned off the breakers inside the Rheem unit one by one until the motor for the blower turned off. I gave it a rest and every time I turn that breaker on the blower motor starts up even though the thermostat has been turned down to 50.
Submitted: 6 years ago.
Category: HVAC
Expert:  BillyHvac replied 6 years ago.




the sequencer (relay) has gotten stuck in the closed position.


This is not a repairable item and must be replaced.


Part -


Rheem Ruud Weatherking Factory OEM Protech Parts 42-23116-08 ...

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Customer: replied 6 years ago.
Billy, Where can I get a sequencer (relay) for my Rheem electric forced air house heater?
Expert:  BillyHvac replied 6 years ago.

They are very common...but I would need the model number to be specific.


Either number from air handler or the part itself.


If you can get one or the other I can assist you further.



Customer: replied 6 years ago.

Billy, the model number of the Rheem furnace is


I couldn't find a part that looked like that one.


The only thing similar to that was part number 42-19423-02 fan relay.

Where is the sequencer (relay) located?

Expert:  BillyHvac replied 6 years ago.

Could it be RBEA instead?



Customer: replied 6 years ago.


I checked the label again and it reads:


SERIAL NO W FO375 1752 (I can't tell if the "O" is the letter or the number "zero")

TOTAL KW 40/30

HTR. AMPS 160/138.7


and then more specifications on the label.

Paul King

Expert:  BillyHvac replied 6 years ago.


yours is configured a bit different.


looks like this


Customer: replied 6 years ago.

Billy, thank you for finding the specific item and including a photo in your last reply.

When I clicked on "View Full Image" it came up in a separate window on my screen with an internet address at the top that indicated it was a webpage from

I assume that carries it. What is the part number in case I can get it from a local furnace repair person or supply house? Is it SL160 ? Also where is this item in the furnace? I can't find any relay or part that looks like this or the other one you sent to me yesterday that is still part of this thread. The web address of the picture may have the part number embedded in it. The address is: The part of the web address that looks like it might be the part number is the "SL160"

Expert:  BillyHvac replied 6 years ago.


Here is the Ruud/Rheem parts manual for your unit. Item 52 is the sequencer and it shows location. The fan relay is just for blower in cooling mode. The sequencer is what we need.



Customer: replied 6 years ago.


I downloaded the Ruud/Rheem parts manual and it was a pdf file. Page two was a nice exploded parts view of the entire unit. I recognized just about all the parts and where they were supposed to go. You had written that Item 52 is the sequencer. I can see what it looks like and where it is supposed to be. ITEM 52 is also shown magnified on the far right and the top of the diagram and and looks like a very small block with spade connections for wires. ITEM #51 ON THE DIAGRAM IS THE FAN RELAY which you said is just for blower in cooling mode. Well that is in the right place and a lot of wires coming from it are going over to the left side of the compartment where the sequencer is supposed to be and the best way I can describe what is over there in the left side on the floor of that compartment are two BIG blocks with a LOT of spade electrical couplings for the many wires that are connected to them and also two more big blocks similar to those are on the vertical wall over in the corner where the sequencer is supposed to be. I found a picture that is generally similar to what these blocks look like even though they may be for some other model but they show you what these much bigger blocks look like. At the following link there are three pictures that give you a general view of a larger block like the four blocks I have - 2 blocks on the left side floor and 2 blocks on the left side back wall vertically in the corner. Each of the blocks are about 2" wide and 4" long each taking up all the space in the left hand corner.

The exploded diagram shows ONE much smaller block AND I HAVE FOUR MUCH BIGGER BLOCKS. Perhaps the diagram shows one small sequencer and my unit is supposed to have 4 large sequencers ganged together. (?)

If that is the case, then since you originally said, "the sequencer (relay) has gotten stuck in the closed position. This is not a repairable item and must be replaced," then HOW CAN I DETERMINE WHICH ONE OF THESE FOUR BLOCKS NEEDS TO BE REPLACED - OR IS IT ALL OF THEM?

Expert:  BillyHvac replied 6 years ago.


That part you found at the supplied link is correct.


The issue is this....if the fan relay is what was stuck, then just the blower would be running and not the heat.


Since it is heat and blower running it is a sequencer. The REAB can various amounts of heat with a number of different heat coils. We do not know which coil of yours is sticking on.


On the sequencer (and especially the one in link) there are 2 terminals that say HTR.


This HTR is where the the thermostat sends it power through...then by use of heat and warp switches, the power of the 24 v from thermostat starts making each set of contacts close at different delayed times. Blower always kicks on first which one stage of heat (one coil) kicking on seconds later....then another will kick on...this prevents all coils needing start up at once.


You now need to find which one is stuck by removing a blower wire one at a time from the sequencers. Turn off power, remove wire and tape..turn back on. If fan starts again, replace wire and move to next one.