Pellet Stove Control board repair Applied Control Electronic DHC 4110

Disclaimer : I'm a self tought hack and don't try anything here unless you are willing to risk wrecking you stuff!! I will not be responsible for any operator error. Just an FYI guide for giggles. Don't believe a word I say cause I'm likely full of sh~~!

I've tinkered with a few of these ACE boards and thought I might share a repair procedure. If you can solder, they are fairly easy to repair. Hard part is getting the old components off without destroying the boards traces! I mainly use 25/40 watt solder iron, solder wick and/or a cheap heat station to get the bad stuff off. Heat station mainly for surface mounts and solder wick for the through board mounts(AKA pin mount).

This board is for my Enviro Omega Its a DHC 4110 -D. From the pic attached you can see C-11383 on the blue relay. That is the code for the software applied for the specific stove manufacturer. The D at the end of the DHC number is the revision. The hand written 2 is me as its the 2nd board I own. Just some FYI.

My issue is the feed auger is sticking or running continuously on this board. The black relay is the main culprit of sticking or auger run on from what I have seen. I'll try to draw a schematic of the auger circuit if possible.

The repair will involve di-soldering the relay. I will use solder wick to absorb the solder. And then carefully remove the relay.

But first I have to remove the needed relay from a junk board. I'll start that later this weekend as I have a few other things to square up at the moments. Just wanted to get a start on the thread/post before I totally forgot!

 

Me learned that from one of the best!

 

I picked up a scope at a tag sale. Use it to see the part numbers and solder the tiny SMT's.

I'm thinking socket some of the common failures on this board to replace with ease at a later date instead of the resolder. Only risk over heating the board traces once instead of several time??

 

I might have one in my hot work station. Never tried it though, But will for sure. I also have the solder iron with the bulb attached. Never had luck with that one.

 

Well most of my stuff came in except the solder sucket. So we had a go with the repair tonight! The dip sockets I ordered won't work as 2 pins on the relay are too large. Going to try and see if another dip socket might work. Going to contact Omron or TE customer service to see what they recomment.

So board #2 just got the one relay for the auger replaced. Price of repair was about $3.50 for the relay and $35 for solder and wick cus I still can't find my stuff from the move! Board is back in the stove and so far(knock on wood). Working as it should! But I'm keeping a close eye on it!!

Board #1(the OE for the stove) with the bad ignitor relay lays in wait to get its relay changed. I may also just change the auger relay as well. Plus a new button for the auger feed. But holding out until the #2 board is good.

Board #3 that went dead looks to be fine(no visible poof markes). Both the fuse and the thermistor are good. Checked all the easy peasy stuff. But looks like now I need to start looking at making a schematic to trace things. I also need to build a work station/test center. So I can power it up and trace it.

 

Board #1 pics with the new auger button. Top left in first pic.

Edit: I also notice board #1 is a DHC-4100 and is slightly different than the #2 and #3 boards!

Front w/buttons


Back with the dead ignitor relay

 

Chitter isn't full anymore.

Honey do list is over full and runith over!

But!, I did work on board #1 today. Cleaned the stove 1st and installed. So board #2 is now the spare. My solder sucker arrived and I got to play! Works pretty good, But I am old school and went back to the wick to get the fine stuff out around the pins. But the sucker should work awesome with the heat station on SMD stuff!! Popped in the new relay and were off and running.

I needed board #2 to trouble shoot board #3!! Board #3 looks to have a dead resistor or inline SMD fuse?? Will find out later!

 

Also no PCB relay sockets for these small relays. Mainly because of the amp draw(normal PCB sockets have a 1 to 3 amp max rating where these relays are 5 amps and 10 amps. So I may make a daughter card and use the next size up relays which do have PCB sockets. Stay tuned for board #3 revamp/upgrade. I may also over size the relays an use 10 amp rated. And then fuse the outputs.

I may also make a fuse panel for all the other components as well??

Stay tuned!