BURNHAM V905( 5 Section) W/ Carlin 301 CRD

Jalen_Jalen2006

very Confusing, been fighting another intermittent burner(No ignition) randomly. Pump pressure is 150 psi, pulling around 3 “ inches vacuum. Went through Carlin process of checking igniter(41000), set electrodes. Now I had to go back again after a month of running, this time I called Carlin and, I discovered a couple things:

1. The damper on the vent was not set for positive pressure. I checked it and it was negative pressure which is incorrect these boilers are pressure fired. So I tried to set that I pretty much had to put it as close to”close” to get it to be (+).

2. We have a nozzle in there a Hago 3.75 x 60 ss though that’s for a 4 section. Even that’s not right the manufacturer calls for 3.75 x 80ss This unit has been running with the settings for a 4 section boiler. The boiler is a 5 section and calls for an entirely different nozzle and nozzle dimension. How is that even possible?

3. A delay in the oil valve, the control goes from oil delay to trial and, there’s a 3 second delay in trial for ignition, Then it will fire.

Pictures below:

EBEBRATT-Ed

In MHO your barking up the wrong tree. It is unlikely that down firing the boiler or having the wrong nozzle is causing your problem. And pressure or neg draft within reason will not cause lockouts.

Check your oil supply with vac and pressure gauges they have to be rock steady

Check the ohms on the cad cell while it is firing. In most cases you want below 700 ohms

Sometimes those ignitors cause more issues that the old transformers

I have also seen electrodes build a carbon bridge across them if they are in the oil spray or too close to it. This will not be carbon that you think of it will be a thread no larger than a hair. You get a call the burner won't light because the electrodes are shorted by the carbon. You remove the gun assy to check the electrodes and the carbon hair brakes and falls off and you pull the electrodes and they look ok.

HVACNUT

What are the combustion numbers? Excess air.

LRCCBJ

Old iron piping for fuel supply.

Do you know how to check for a suction line leak with a vacuum gauge? You'd need a 1/4" vacuum gauge, an operational shutoff valve as close to the tank as possible, and you'd need to install a 1/4" tee at the pump inlet (after the valve).

Jalen_Jalen2006

https://forum.heatinghelp.com/discussion/comment/1847240#Comment_1847240

I mean I can try it, I was pulling 3” inches of vacuum. Gauges never hurt though

LRCCBJ

You shutoff the fuel as close to the tank as possible.

Start the burner (you'll need to jump the safety after it starts).

Run it for about 30 seconds and watch the vacuum gauge. It will climb up to 12-15" or so vacuum.

Watch the gauge.

Shutoff the burner.

Watch the gauge.

It will drop………..maybe 2"………….and STOP. It will stay at that reading……………indefinitely………….IF you don't have a suction leak AND the pump seal is good.

If it slowly falls over the next 15 minutes…………….you DO have a suction leak or a leaky pump seal.

If it quickly falls to zero (in one minute or so), you have a BIG suction leak and now must locate it.

techforlife

Sounds like an intermittently failing electronic ignitor. Famous for that.