Author Topic: My cb2800 won't start ... thoughts or ideas?  (Read 86878 times)

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Re: My cb2800 won't start ... thoughts or ideas?
« Reply #45 on: February 14, 2015, 08:37:21 pm »
I would watch oil pressure and make sure it is not dropping. Did you get the Lenz filter with gauge that mounts before the pump with the heater ? Watch that gauge and if it starts dropping to 10" of vacuum you need to clean filters.

Another thing is compressed air. Is the compressor keeping up ok on the longer runs ? The air proving switch needs at least 30 psi to turn the pump on. I like to install an air filter regulator and set it at 50-60 psi.

gte

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Re: My cb2800 won't start ... thoughts or ideas?
« Reply #46 on: February 15, 2015, 03:21:45 pm »
I adjusted everything as you recommended, I had to turn up the oil pressure to stop the below from happening though and the flame is pretty strong now. Is there something else I can try to keep it running? It seems to not want to restart itself?

Cleanburn flameout 1: http://youtu.be/mu15mxOD3UI

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Re: My cb2800 won't start ... thoughts or ideas?
« Reply #47 on: February 15, 2015, 03:34:06 pm »
Oil pressure bouncing = sucking air somewhere between pump and suction screen. That gauge on the Lenz filter should be at 0" or somewhere in between to 10".

Oil pump plumbing is my #1 thing I tell my customers no ifs ands or butts about it, we are doing it my way.

Could you take a picture of the oil pump and tank setup ? Lets see if we can make any improvements in that area.

gte

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Re: My cb2800 won't start ... thoughts or ideas?
« Reply #48 on: February 15, 2015, 04:55:53 pm »
Hi,

It seems to be starting and acting more normal now that I turned the pressure up to ~4psi from ~3psi, although the flame travels pretty far back now in my opinion. Here are some pics of the setup and also a video from the tank to the burner to help make it more clear. The needle still does fluctuate, but not as much now.

Trying to watch the gauge as I start it, I don't see it move much and I'm concerned it might not be moving at all. Is the oil pressure gauge oscillating something that is abnormal? Is it usually dead set once it gets going and holds steady? If not an air leak, could anything else cause that? I'm not the best at solder copper, but I would think that any air leak that could cause the gauge to fluctuate, would also leave a significant amount of oil on the floor when the pump wasn't running (low side) or when the pump was running (high side).

Thanks.

Cleanburn setup1: http://youtu.be/mYUUutGCsZU






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Re: My cb2800 won't start ... thoughts or ideas?
« Reply #49 on: February 15, 2015, 05:21:16 pm »
I would definitely redo the whole pump setup.

Pump on top of tank - 1/2" hex nipple screwed into pump - 3/4"male to 1/2" female swivel for Lenz outlet - 3/4" street L for Lenz inlet - 1 piece of 3/4" black pipe long enough for the p/u screen to be at roughly 3" off the bottom of tank - 3/4" check valve goes on pipe and p/u screen screws in to it.

Loctite #2 gasket sealer for threads and tighten everything tight plus another turn.

This way when it comes time to clean filters you only have to loosen the 1/2" swivel to remove with stand pipe so both filters get cleaned at the same time. 

The gauge on the burner should go up to set pressure and not bounce around at all. I have had suction side air leaks but no oil leaking out. It can be quite frustrating so I eliminate as many fitting as possible and plumb it the way I do. 

gte

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Re: My cb2800 won't start ... thoughts or ideas?
« Reply #50 on: February 16, 2015, 12:35:40 am »
I will redo it then, I want to make sure it will work properly first. The machine is cutting itself off for no reason. I watch the oil gauge so I know it isn't oil pressure, even though it is fluctuating.

Could the flame light sensor be going bad? What else could cause the sudden and random shutoff issues? Is there a way to bypass the flame sensor? Does it work off of resistance and I could use a resistor to test it instead?

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Re: My cb2800 won't start ... thoughts or ideas?
« Reply #51 on: February 16, 2015, 12:57:19 am »
The fluctuation can cause it to shut down. The cad cell (flame sensor) needs to a see a good bright flame or it will tell the primary to shut down. Every time the oil pressure drops it sees dark and if it sees enough dark it locks out. Sucking air is the #1 problem I see with heaters. The smallest amount of air can cause all kinds of problems.

Do not bypass the cad cell unless for test purposes only. If you leave it bypassed and the flame happens to go out the heater will keep running thinking there is still a flame and you will fill the firebox full of oil. I have seen this and it is a ugly mess and a potentially huge fire risk.

Make sure the cad cell is clean then work on the fluctuation issue.

gte

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Re: My cb2800 won't start ... thoughts or ideas?
« Reply #52 on: February 16, 2015, 08:49:08 am »
It will be a bit before I can rebiild the low pressure and high pressure lines. Can I use cpvc on both sides? If not I will have to figure out where to get alll of the fittings and adapters you suggested.

I cleaned the sensor today and noticed that it seems to be working consistently for a few hours now. I'm not convinced it is going to keep working though. I also noticed that the flame sensor will generate between 4 and 6 volts DC when running. Is this correct? Do they have a wiring manual and specification for this unit? If it stops working again I can at least check that voltage level now for testing with my meter.

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Re: My cb2800 won't start ... thoughts or ideas?
« Reply #53 on: February 16, 2015, 11:33:14 am »
The 3/4 pipe and street L you can get at Home Depot/Lowes. The swivel and hex nipple you can get at a place that does hydraulic hoses. Black pipe and black pipe only for the stand pipe. For the pressure side I like to use 3/8" nylon like what semi trucks use for air lines and quick connect push in fittings.

The cad cell is measured in Ohms. The brighter the flame the lower the ohms. Hook your meter up where the 2 yellow wires connect at the primary control with heater off take note of reading, fire up heater and take note of reading. While the heater is running watch the meter while adjusting oil pressure you will see the ohms change and that should give you an idea of how low of oil pressure you can have before it shuts off. 

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Re: My cb2800 won't start ... thoughts or ideas?
« Reply #54 on: February 16, 2015, 02:05:25 pm »
I did what you described with resistance previously when checking the voltage, my meter is auto ranging and resistance would jump all around from 6k to 16k when off, it was strange. Voltage seemed a little more consistent, 0vDc when off and 4 to 6vDc when on. The resistance measurement when on was about 250 ohms. It is still running by itself now 5 or 6 hours later and responding to the thermostat correctly. Aside from redoing the low and high pressure lines, I will have to keep an eye on it and see if it will run autonomously now.

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Re: My cb2800 won't start ... thoughts or ideas?
« Reply #55 on: February 16, 2015, 02:20:18 pm »
250 ohms is good, I like to shoot for 500 or less. The ohms reading will jump around if oil pressure is bouncing around as your flame is changing. The cad cell resistance changes according to brightness of flame. You can unplug just the eye and test its resistance with darkness and a flashlight.

gte

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Re: My cb2800 won't start ... thoughts or ideas?
« Reply #56 on: February 16, 2015, 08:17:48 pm »
Great news, it is still working on its own. I'm not going to abandon the replumb but it would be great if I could do it at my own leisure and not be rushing around trying to get it working in this cold spell we are having and small snow storm. I wonder how to figure out how much oil it is using at 55F room temp?

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Re: My cb2800 won't start ... thoughts or ideas?
« Reply #57 on: February 16, 2015, 08:54:13 pm »
That heater burns about 2 gallons per hour so if you keep track of hours on the meter you just take that number x 2. It will give you a close estimate.

That is what I like to hear. I think the best part about it is no money was spent to get to this point.

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Re: My cb2800 won't start ... thoughts or ideas?
« Reply #58 on: February 17, 2015, 05:45:32 pm »
You are absolutely right, that is the best part and as a nice side effect, I know a lot more about these units than I did 2 weeks ago ... I might even be able to service and clean it on my own now :)

So more than 24 hours later it is still running and maintaining the proper temperature. I notice that it add 1/10 of a running hour for every actual hour ... at least today it did. So using that number/ratio it will run for 2.4 hours a day and use 5 gallons of oil a day, does this sound correct? Or about 150 gallons a month in the winter conditions like I'm having now. If correct, this is a good way for me to know how much waste oil I will need for the years to come ... probably around 600 gallons each winter.

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Re: My cb2800 won't start ... thoughts or ideas?
« Reply #59 on: February 18, 2015, 01:27:49 pm »
My dad went to check on the heater and he said that it had turned off, so I'm going to test it when I get home.

I was going to test for voltage and resistance to compare it to the previously noted values. I was also going to bypass the thermostat to see if it turned on (indicating a thermostat problem) . If it does not turn on when I bridge the thermostat terminals and it has air pressure, do you have any other ideas for what I should check for? Can I test for voltage values in the electrical connector inside of the burner?