Switching from two pipe to single pipe on beckett pump 103220

threepcreep

Hello all. I'm switching over from a two pipe system to a single later this week. My pump is a beckett clean cut pf 10322 with valve on delay (currently enabled with a return line). I know I have to remove and plug the return and reconfigure the control (Honeywell r72f4u) to disable the valve on delay when I switch over. I just wanted to make sure I'm not missing anything beforehand. Dont want to have to buy another pump. Thanks.

HVACNUT

Well you might want to attach this to your other thread so we can see the history.

You don't need to touch the primary. You'll still have pre purge with one pipe.

threepcreep

> @HVACNUT said:
> Well you might want to attach this to your other thread so we can see the history.
>
> You don't need to touch the primary. You'll still have pre purge with one pipe.

How does valve on delay work with no return?

SuperTech

The solenoid valve can be used with single pipe or two pipe setups. The number of oil lines have no effect on the operation the primary control or solenoid valve. Why would you want to get rid of pre purge or post purge?

threepcreep

I assumed that the oil that runs through the pump before the valve actuates went through the return and back to tank. I'm simply trying to figure out what I need to do to the pump before I switch it to a single line.

SuperTech

Just remove the bypass plug and then put a plug in the return. That's the way a new clean cut pump is out of the box. All new pumps need to have the bypass plug installed to convert the pump for two pipe usage.

STEVEusaPA

threepcreep said:

I assumed that the oil that runs through the pump before the valve actuates went through the return and back to tank. I'm simply trying to figure out what I need to do to the pump before I switch it to a single line.

Yes that how it works on 2 pipe with plug installed. On one pipe, no plug installed, the fuel basically bypasses internally.

EdTheHeaterMan

To better understand the oil burner fuel unit (pump) one must understand the gearset of the pump section is a positive displacement pump. (as opposed to a centrifugal pump like a circulator on a boiler). This means the fuel pump will move the gearset capacity and build up hydraulic pressure. As the pressure increases the hydraulic pressure forces the pressure regulator valve to open based on the force applied by the pressure adjusting spring. Once the pressure is sufficient to open the cut-off valve, oil flows to the nozzle port and is restricted by the nozzle firing rate orifice.

Since the nozzle only allows a small percentage of the oil to exit the nozzle port, the balance of the gearset capacity is bypassed to the return port. On a 2 pipe system, the by-passed oil returns to the tank. This is ensured by installing a bypass plug in the pump.

On a single pipe system, the bypassed oil is returned to the inlet chamber through a bypass port when it is not plugged.

so the oil that is not used by the nozzle is always sent to the return port. if you plug the bypass then you need to attach a fuel line from the return to the tank (the second pipe). If you leave the bypass port open (no bypass plug) then you do not use a fuel line from the return to the tank, you just leave the factory installed 1/4" plug unopened.

it is all explained here:
http://www.suntec.fr/wp-content/uploads/2018/11/Installation-and-Service-Manual.pdf