Rheem M266A Pool Heater Troubleshooting

StLouShark

New member
Apr 29, 2020
2
St Charles, MO
I have a 10 year old model P-M266A-EN-C pool heater for my salt in ground liner pool. At pool start up this year at first heater operation it ran for a couple hours and then gave a CLK message. While not actually being a HVAC guy or a pool guy, I was a dealership auto mechanic back in the 80s and an ex-Air Force ground power tech before that. I have investigated Rheem/Raypak repairs on the internet, YouTube and with friends that service their own pools to try to diagnose and repair the heater myself but haven't been able to come up with a reliable way to follow thru diagnostics.

It seems to me that the CLK, (fireman switch), message is not really any kind of error code. It's just telling me that the safety circuit shut the unit down and the unit is waiting for messaging to fire back up. I think that I need to walk thru diagnostics on it to find the correct error message but can't find any reliable instructions.
I have a pool owner friend with the identical setup that convinced me that we should switch out my circuit board with his, (identical & same P/N), to see if it fixes the problem. We did that and the furnace was operational. We let it run for 10 minutes, or so, and he believes that is the issue. This still brings in some concerns. I'm really not sure what is the correct replacement circuit board for my P/N 601769 board. I think 013489F, but I'm not sure.

Also, I have seen some forum messaging from people with similar issues that have replaced their boards and had the problem come back within a short period, (anywhere from a week to a couple of months), afterwards. The part is definitely too expensive to be guessing that it should take care of the problem. If anyone could confirm my suspicions or point me to some reliable servicing information or a company that I can work with to walk thru diagnosis, I would greatly appreciate it.
 

RDspaguy

In The Industry
Mar 21, 2020
712
Cabool, Mo
Hey, someone from my home town! Love it.
To fix this yourself, this forum is probably your best bet. Pool professionals pay their bills and feed their kids with their knowledge, and are not likely to give it away for free in their own service area. You don't work for free, do you?
The advantage, in your case, to hiring someone is that if the problem does return you are covered. Any reputable service company will at least apply your previous bill toward the appropriate fix if they made a mistake. I would be happy to recommend a couple of places with whom I have worked for decades, but you already know their names if you live in StC.
 

StLouShark

New member
Apr 29, 2020
2
St Charles, MO
I don't work, except for trying to keep everything going around the house, Retired. Your probably referring to Four Seasons or R & S Pool and I may end up having to give one of them a call. But I do enjoy the challenge of trying to figure out whatever I can and fix it myself, if possible.
I have made some headway, Figured out how to read the error codes on my heater unit and how to clear all of the codes. Did that after reinstalling and the heater is working, at least right now. The most common error code of the 32 was a PRS code which comes from a pressure sensor that makes sure there is enough water pressure pushing water thru the unit. If I get that code again I will try replacing that sensor. If it still gives me trouble I will probably put out the $200 and try replacing the circuit board myself. If I still have trouble after that I will bite the bullet.

Thanks for the reply,
StLS
 

RDspaguy

In The Industry
Mar 21, 2020
712
Cabool, Mo
Yep, R&S has been my main supplier for 25 years. I worked there for a few years, too. They would be an excellent choice, as would St Charles pool and spa. The long-time tech turned general manager of R&S, Kenny Ettling, opened up his own place in his home town. They are in Cottleville by the QT, 94 and O'Fallon rd. He does much of his own field work, so you can get a lifetime of experience in your backyard.
Both are reliable, ethical businesses and would honor their warranty without question.