Riello RDB oil pumps

[Boatingcow]

I've been asked to look at a system that has had some work done by a previous engineer. The boiler was suffering from flame-outs and the previous guy ended up replacing the oil pump. The boiler is still cutting out, and after checking the usual suspects, (oil pressure, water in tank, pump pressure, nozzle, etc) it looks like the solenoid valve isn't allowing sufficient oil at the nozzle. It sounds suspiciously like the previous symptoms, but this is apparently a brand new pump, so before I replace it, does anyone know the specification for the valve to check it's within bounds (spring force, actuation distance)? It's an RDB 1. Thanks

 

[Best]

I doubt it is the oil pump. Rarely do I ever find a new part doing same fault as the old.
When you say flame out, - what do you mean? Does the flame start to noticeably sound like it is fading, - or is it just a flame failure?
Could be control box, or photocell, or solenoid faulty.
That's if you checked the oil filter is clean and oil flow at hose is constant flow.
Do you have a Tigerloop connected?
Also maybe stating the obvious, but hope burner isn't over aired, as that would result in failed cold starts

 

[Best]

Motor capacitor also can be causing regular sudden lockouts

 

[Chalked]

Hi
What's you FGA readings?

 

[Boatingcow]

Thanks for the thoughts. The flame builds on ignition as normal, then fades to intermittent, then out. I haven't done any FGA yet as there hasn't been a decent flame! Oil flow, Tiger loop, air reg all seem ok. I had tested the coil with the multimeter and that seems fine. Anyway, turns out I had the same pump on an old burner, so swapped it to see last night and sure enough seems fine - steady flow of oil, nice flame. I haven't looked at the solenoid valves to compare yet (late), but pretty sure that's the culprit. Suspicious yes, but I've learned never to rule out the improbable - I might not have the 100% truth from the owner! Still wondering what the spec on the valve is - the valve on the original pump doesn't seem to have any noticeable lift?

 

[Stigster]

Intermittent faults can be caused by the solenoid nearing total failure. Sometimes the electromagnet is just about holding the valve open and as it heats up the solenoid can no longer hold open and it drops.

 

[SimonG]

Over aired.

 

[SimonG]

Get it running before changing anything else.

 

[Boatingcow]

And the culprit was... dodgy fuel. The old pump I fitted didn't make any difference after all over the day. I took a fuel sample and let it settle and noticed something odd like the fuel was forming clumps. I asked the owner and apparently they had put in an "additive" to make it run more efficiently which they "forgot" to tell me about. I've put their boiler back together, told them to get some fresh fuel then we can talk again. Not sure what it was but at best their boiler didn't run, at worst could have been dangerous. I dare say I'll be on "holiday" when they call back. For anyone interested, the solenoid valve is a needle type not plunger, and the pin is internal to the stem.

 

[Best]

Are you sure it isn't some water in the oil?

 

[Boatingcow]

The paste didn't show water as present, but it might well be because of the chemical. I didn't do a pH test. Don't think I'll be back to find out - the owner was, "interesting".

 

[Stigster]

The clumping could be bacterial contamination. That can show as a clumping of debris which is actually biomass/bacteria.

 

[belljohn56@gmai]

I've been asked to look at a system that has had some work done by a previous engineer. The boiler was suffering from flame-outs and the previous guy ended up replacing the oil pump. The boiler is still cutting out, and after checking the usual suspects, (oil pressure, water in tank, pump pressure, nozzle, etc) it looks like the solenoid valve isn't allowing sufficient oil at the nozzle. It sounds suspiciously like the previous symptoms, but this is apparently a brand new pump, so before I replace it, does anyone know the specification for the valve to check it's within bounds (spring force, actuation distance)? It's an RDB 1. Thanks

replace the solenoid the magnet could be gone they're only £29 and also replace the nozzle.. and also check the oil for water

 

[Best]

replace the solenoid the magnet could be gone they're only £29 and also replace the nozzle.. and also check the oil for water

I wouldn't pay £29 for an RDB solenoid. That must be retail price

 

[SimonG]

£29 for a solenoid. That's a good one. I don't even charge them to my custs for that.