Harman Help PB105

[boiler]

I have picked up a used pb105, it was/or could of been damaged by a sprinkler system. I have connected the boiler, and proceeded to turn it on when I have encountered the status light blinking three flash which indicates a fault in the ESP probe. I went to my local harman dealer and purchased a new ESP and installed it. IT did not cure the flashing three light on the status...

I returned to the dealer explained my problem and we came to the mutual agreement that it must be the control panel. So I purchased a new CP. Installed the new panel and I still have the flashing three error..

Anyone have any good ideas?

 

[Hydronics]

I have no experience with that boiler but I'd check for continuity between the probe and wherever it sends a signal to/from, I assume it's the controller. Hopefully you have a wiring diagram. Can that code indicate any other issues?

 

[boiler]

In the owners manual it says its only the ESP probe. (exhaust sensing probe)

 

[boiler]

After reading the thread below, I discovered that I did not have the dip switches all turned down on the new CP. All is well, the boiler is running normal. New ESP $80...new CP..$200. DIY Plumbing installation about $400. Stove pipe $300. Used PB105 $3000. So for under $4000 I have a excellent running PB105.


https://www.hearth.com/talk/threads/harman-esp-test.106847/

 

[boiler]

OK, so I could use a little more help.

After replacing the esp probe, the control panel, and the aqua temp.sensor. The water controls still do not work. Only the "off" works on the low temp knob.

Right now I'm running 2 on the feeder knob, and still going thru 3.5 bags a day.

 

[Mr._Graybeard]

I've read on this forum that placement of the aqua temp sensor has to be fairly precise or you'll have performance issues. To far from the bottom of the well, and it'll overheat; too close and it'll shut down early.

Perhaps you've read this thread from the archives -- if not, there are some good observations by MikeN and ScotL toward the end. https://www.hearth.com/talk/threads/the-harman-pb105-tell-me-about-it.107740/#post-1436231

 

[boiler]

thanks for your reply, I did read that thread/post.

I should of added to my post that when I bought the pb105 it didnt have a aquastat well so I picked one up at the local plumbing store, its a brass well which is 4 or 5 inches deep, I did make a copper shim to hold the probe tight. How deep is the stock aquastat well?

 

[Mr._Graybeard]

thanks for your reply, I did read that thread/post.

I should of added to my post that when I bought the pb105 it didnt have a aquastat well so I picked one up at the local plumbing store, its a brass well which is 4 or 5 inches deep, I did make a copper shim to hold the probe tight. How deep is the stock aquastat well?

Not sure about the aquastat well depth, but I'm wondering if the heat conduction to the aquastat is at fault. Sounds like your boiler is really cranking if you're burning over 3 bags a day at a 2 feed rate but the aquastat isn't detecting it.

I've never had to tinker with the aquastat, I'm happy to say, and hope it stays that way. So take my thoughts with a grain of salt. It seems like the most fiddly part of the boiler control system.

 

[boiler]

Of course when you buy the sensor it doesn't come with the spring and plastic part.

Thankyou for your input.

 

[Mr._Graybeard]

Here's the part number for the immersion well -- it's a Johnson Controls WEL 11A-601R. Is that the well you installed? Here;s one on eBay that comes with a spring: http://www.ebay.com/itm/Johnson-Con...142?pt=LH_DefaultDomain_0&hash=item43d7ba75de:

 

[boiler]

No, here is the one I used.

http://www.ebay.com/itm/Honeywell-1...329?pt=LH_DefaultDomain_0&hash=item58bd1848a1

 

[boiler]

There is quite a difference in the two. There is no jacket for the Honeywell.

 

[Mr._Graybeard]

For $10 it might be worthwhile to give the JC well a try.

 

[boiler]

Just ordered it. I'll post back in a few days after I get it installed. Thanks for your help.

 

[boiler]

Installed and working properly. Although its completely obvious that I'm going to have to add some zone valves on thermostats.

 

[Mr._Graybeard]

Good to hear. Overall my boiler has been a steady performer throughout the last three heating seasons. Hope yours is the same now that you've got it set up better.

 

[boiler]

I'm sure it will be. I still need to add some zone controls, but that's the easy part now that it's performing normally.

Now that it's in the upper 20s low 30s I'm literally turning on for an hour in the morning and an hour in the evening. oh the joy of thermal mass.