Burnham Alpine ALP210 High Limit Reset Sensor Error, Main Board problem?

[SCaNH]

I have an ALP210 that was installed in our new home in October 2014. It's worked fine until a couple of months ago. The problem used to occur occasionally but now it happens at least a few times a day.
The system will be "running" according to the front panel display, and the supply temps are showing much higher than what the actual temp gauge in the supply line shows. The boiler runs but it's not actually heating up anything and thinks the supply temp is like 129 when it's really cold like 70. A reset of the power and it immediately reflects accurate supply temps and returns to normal operational by starting up and heating everything back up.
When I check the help -->fault status on the LCD it shows the High Limit Reset as open, but the rest down the line are not open and all wiring passes continuity checks.
Could the problem be the main board itself?
Seems the likely culprit since the high limit sensor and the circuit it's in all seem fine.
Just looking for any other people that have experienced this situation and had to solve for it.

Thanks

 

[Leon82]

I would want to make sure the sensor was good before replacing the board.

The service manual may give a voltage range for a temp. Possibly in millivolts

 

[Sponsor]

 

[SCaNH]

Thanks for replying Leon82.
I checked the sensor itself and it's fine. The problem seems to be happening more often now 3 to 4 times per day. There are no other indications to go off of other than the auto reset high limit sensor error on the limit string status screen. It just seems odd that the supply temp measurements get stuck at incorrect temps causing the boiler to think all is well when it's not. Guess I'll have to call US Boiler and check my warranty before calling a local boiler tech in to check this out. I'm not calling the guy that installed it. I want in independent assessment of the problem.
If anyone has any other suggestions on what to check, I'd appreciate it. Thank

 

[Pkotha]

I am getting the same error and power reset is not clearing the error.
Did you replace high limit sensor ..? If so, how did you do it ? do you release any pressure or simple replacement of the part
Burnham 101653-01 Alpine High Limit Sensor

 

[Jadnashua]

I'm pretty sure that high limit is a temperature value, and not pressure related. Does that system have primary/secondary loop setup? The primary circulation pump may not always be coming on which will quickly cause the primary loop's temperature to get too high, and little to no heat in the secondary (the loop that feeds the rest of the system) loop. If that pump eventually starts, things will return to normal.

 

[Mage182]

ALP150 user here. Can you upload some pics of your piping setup from the boiler to the zone pumps/valves? In my experience with these sensors having problems it's either the sensor itself or some sort of flow (or lack thereof) issue.

 

[annelisemcl]

Did you ever get a fix to this problem? I am having the same issue on my Alpin 150 modcom & even with a new kit installed, it is still faulting open. Rep & tech suggestion is replacing the board at over $600 but I don't want to do that if it is not necessary.

Mage182, what problem with piping may cause this? Asking because my tech said the original installer plumbed this incorrectly but it has worked for 7 years, so the tech said to wait it out before redoing the plumbing.

Ann

 

[Mage182]

Your interface is a newer version than mine. Is that high limit referring to stack temp? If so there is a stack temp sensor which is the problem I had. The way it was originally designed allowed the condensate to come in contact with the sensor which caused it to fail. The replacement I bought had some sealant that fixed the problem. The failed sensor would return flue temps much higher than actual so the unit would only run for a short period of time before hitting the max and shutting down.

Can you provide some pics of your install?

I had to replace my control module after it blew up during Sandy. It's important to note that the replacement boards are not model specific and come locked on the ALP80 configuration. A technician code is required to change that and I have not been able to find out what it is. I've been running my 150 model on the 80 config and haven't had any problems, but I'm not sure if it's optimal.

 

[Tom3holer]

That is very interesting what you said about being locked in the AL80 mode
My situation was that my incompetent plumber that I hired to replace my old boiler put in an Alpine 150 which was way too large for my home and it short cycled all the time. I arranged to have the plumber meet with the Burnham factory rep and had him explain that he had way oversized the boiler. The plumber then replaced it with a AL 80 which had been mostly working well. I am sure simply changing the boiler size in the setup would not have made it modulate down as low as a 80 does.
On another note I also had a Hi temp sensor fail and replaced it and all is well again.

 

[Aimo]

That is very interesting what you said about being locked in the AL80 mode
My situation was that my incompetent plumber that I hired to replace my old boiler put in an Alpine 150 which was way too large for my home and it short cycled all the time. I arranged to have the plumber meet with the Burnham factory rep and had him explain that he had way oversized the boiler. The plumber then replaced it with a AL 80 which had been mostly working well. I am sure simply changing the boiler size in the setup would not have made it modulate down as low as a 80 does.
On another note I also had a Hi temp sensor fail and replaced it and all is well again.

That is very interesting what you said about being locked in the AL80 mode
My situation was that my incompetent plumber that I hired to replace my old boiler put in an Alpine 150 which was way too large for my home and it short cycled all the time. I arranged to have the plumber meet with the Burnham factory rep and had him explain that he had way oversized the boiler. The plumber then replaced it with a AL 80 which had been mostly working well. I am sure simply changing the boiler size in the setup would not have made it modulate down as low as a 80 does.
On another note I also had a Hi temp sensor fail and replaced it and all is well again.

That is very interesting what you said about being locked in the AL80 mode
My situation was that my incompetent plumber that I hired to replace my old boiler put in an Alpine 150 which was way too large for my home and it short cycled all the time. I arranged to have the plumber meet with the Burnham factory rep and had him explain that he had way oversized the boiler. The plumber then replaced it with a AL 80 which had been mostly working well. I am sure simply changing the boiler size in the setup would not have made it modulate down as low as a 80 does.
On another note I also had a Hi temp sensor fail and replaced it and all is well again.

I have an Alpine 210 installed in 2015 (in Canada) and have the same issue where the limit string error message shows the Auto reset Hi Limit as being “open” - I followed the wiring from terminal J6-3 to the switch (two GY - grey wires) and pulled the plug and inserted a jumper across the plug terminals and the boiler started functioning again In the Installation Operating Manual (update of 2017 available online) shows that if this switch “opens” all subsequent downstream interlocks should show them being open as well (not as shown above in the picture shown above in this string of comments?)
Last December my boiler shutdown as it was not getting gas - two separate techs replaced the gas valve at great expense - still didn’t work - the factory trained rep was on the phone for what seemed hours back and forth and then a manager in the tech Dept at Burnham/USBoiler suggested looking at the wiring plug which apparently is a DC converter from the 24VAC to 24VDC- the tech said his meter showed voltage going the solenoid but it was AC and the solenoid needed DC voltage to hold the coil in! The wiring plug/converter was cheap compared to buying two gas valves which distributor would not take back ! Great service! Not sure if this is USBoiler policy that is imposed on their distributors ?
My boiler was totally offline from For 17 days !!! (Temps we’re minus 20 degrees celsius during most of the period mid Dec to late Dec - luckily I had a 6kW elec heater available (used during construction of my house) and a gas fireplace. ) Techs were busy and UPS took 7 Days to ship an overnight delivery for parts from the US to Canada - think about parts availability if anybody is thinking of buying boilers.
I paid more in parts and service than I paid for the original unit! Which was less than two years old! Two failures in two months! I decided to try the last fix myself, if I can buy a replacement limit switch - not found yet though.

 

[Ron Beck]

FYI, the plug for the limit is inserted 180 degrees off. Slide the door open and the second plug from the left on the back row, pull it out, rotate it and plug it back in. This is a four wire plug with 3 wires. The unused port in the plug should be on the right and yours will be on the left. Anytime anything is flashing on the Limit String screen everything after it should also be flashing due to a series circuit but the problem is the first flashing box.
I would reduce the high fire rpm's since the boiler is so oversized giving a chance for better modulation.

 

[Nare Bhushan]

I have ALP 105, installed in August, 2015. Worked great till this year with some minor issues. This year I got it serviced in Sept and with first cold day in Oct it had a hard lock code 4. I reset it, worked for 1 day then again had same hard lock. The tech who serviced it came back and did some adjustments, removed any air and changed supply temp from 130 to 180. Worked for 2 weeks and again same hard lock. If I reset it, the display shows temp increasing, some bang bang noise and it reaches to 210 and then it gets hard lock. This happens in 2 mins of resetting. I am having tech come tomorrow but not sure if he can diagnose it correctly. What could be problem here? Any suggestions?