Rheem P-M406A-EN-C Natural Gas heater with IID ignition won't fire

kentga

0
Jul 10, 2016
3
Douglasville, GA
Chlorine in-ground 35,000 pool. The heater is 5 to 7 years old and this is the first season I've had problems with it.

The unit is in "Remote Off" and I do not have a remote.

Here's what I get:
1. Switch on unit is "Off".
2. Turn switch "On".
3. Get "RV 1" for a few seconds
4. Then get "CFH" for a few seconds
5. Then get "CLK" for the remainder of the time

Same result if Mode is Spa or Pool.

If I use Mode from Spa to Off to Pool all I get is "CLK"

Never see "SPK"

All of the wires seem to be in good shape but I have not looked at any other than what you can see when you pull off the front cover.

The unit has come on and heated up a few times but it will not recycle to heat again.

Thanks for any assistance.

Kent from Georgia
 
Is the heater wired from time clock with a fireman switch on it. Usually if clk is displayed it means time clock or fireman switch is keeping heater off. Since the display is working the heater is getting power so check the fireman switch
 
If there is no fireman switch attached, you probably have a bad board then. I have seen this a few times most recently and when I removed the board there was a tree frog that had gotten in on the board and shorted it out. It was sandwiched between the board and the back side of the front bezel. So you won't see it till you remove the board.
 
If there is no fireman switch attached, you probably have a bad board then. I have seen this a few times most recently and when I removed the board there was a tree frog that had gotten in on the board and shorted it out. It was sandwiched between the board and the back side of the front bezel. So you won't see it till you remove the board.

As mentioned, the heater is a "stock" heater and it has worked well for 5 or 6 years, and it has come on two or three times this season, but will not re-fire. Can you tell me where the fireman switch is located (if I have one) and what it looks like. It has electronic ignition. I'll check it and also check the board. I have acouple of other questions:

1. Does the top just "pull off"? I need to get some leaves out of there.
2. Do you remove the control board from the front or does the board come off with the whole side plate itis attached to?
3. How do I check the fire switch to see if it is working properly? Ohm meter or volt meter?

Thanks for all of your help. I really appreciate it.

Kent
 
Yes the top does come off. Push it to one side of the other. To get to the control board you remove the front of the heater via the thumb screw, and then the center bezel has two screws on each side. Then it flips down for access to the board.

If you are not sure if you have a fireman's switch, I would then guess you don't have one. It is not a standard piece nor are many of them installed these days.

So I still bet the board is bad. You more than likely will not see any damage to the board unless something like a frog shorted it out. Not sure if you folks in GA have the tree frog or lizard issues like we do here in FL.
 
Yes the top does come off. Push it to one side of the other. To get to the control board you remove the front of the heater via the thumb screw, and then the center bezel has two screws on each side. Then it flips down for access to the board.

If you are not sure if you have a fireman's switch, I would then guess you don't have one. It is not a standard piece nor are many of them installed these days.

So I still bet the board is bad. You more than likely will not see any damage to the board unless something like a frog shorted it out. Not sure if you folks in GA have the tree frog or lizard issues like we do here in FL.

Yes we have tree frogs, lizards and field mice. A field mouse shorted ou a panel on my AC condenser unit a couple of weeks ago.

Let me work on the ideas and suggestions. If my control board is bad, where is the best place (not too expensive) to buy one? By the way, downloaded some troubleshooting material and this guy that helps me some can do some troubleshooting.

Thanks again,

Kent
 
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