Home heating burner squealing

[ronan]

Turned on the central heating last night and a few minutes later there was a squealing coming from the shed where the burner/boiler are. Went out for a quick look and could not do much, too late in the evening.

I assumed from the noise that a bearing had gone in the motor, took the thing apart today and the bearings are fine. The jet seemed to be blocked, covered in crud, so i bought a new one.

The only other thing i can think it might be is the pump. Its a french suntec, a gear pump, it does seem a little bit notchy but gear pumps are sort of like that.

Any heating engineers have any other ideas ?

 

[RonA]

Is it an oil fired spinning cup type burner.? We had loads of them all over the site when I worked, it was a common failure mode for the bearings to pack up, that & the ignition coil/fire eye flame detector.
RonA

 

[ronan]

No its a pump, pressure through a nozzle, kerosene.

 

[julianf]

Depending on how ancient it is, you may be able to power up the motor manually, possible even without the pump connected, and see what sort of a racket it makes then.

If you start thinking its the pump, take a photo of it, and post it up here before you go buying a new one. I have an unused one here, that i purchased for god-know-how-much and i cant even remember now why it wasnt used!

 

[ronan]

Its 22 years old, never gave a minutes trouble, i used to do a bit of maintenance on it every year, clean the electrodes, new nozzle if it was needed, filters cleaned. I have spun up the fan motor with the drill and thats fine, nice and free, no noise. From my searching on the web, it seems most of the trouble comes from the fuel pump.

 

[julianf]

Is it an electro oil burner?

Has like a sunflower / orbit type pattern on the back of the unit?

edit: electro oil were probably a bit earlier - i had a unit from the mid 1970s - was stil running fine when i updated!

 

[carbon]

Think pressure regulator can stick on these if it’s not noise from the pump gears. Picture of the pump would help. Should be able to turn pump by hand with the plastic drive in place

 

[ronan]

Its a normal bentone oil burner, the pump seems to be the culprit, everything else is ok, the pump is notchy and has galling on the drive shaft where it fits into the pump body.

 

[ronan]

Whats the point of the solinoid on oil pumps ? I should know but i don't.

 

[waddycall]

Turns the oil on and off. The burner purges the combustion chamber before the solenoid opens and the burner lights. It also gives a positive shut off.

 

[julianf]

Its a normal bentone oil burner, the pump seems to be the culprit, everything else is ok, the pump is notchy and has galling on the drive shaft where it fits into the pump body.

I'll take some detailed photos of the unit I have here tomorrow. I'll try and get them to you before lunch.

 

[Stueeee]

Does the pump shaft run on an Oilite bearing? this bearing -which is on the "dry" side of the Danfoss pump's seal needed a good soaking in oil on my 15 or so year old Monoflame burner. This had been blowing the fuse once it had run for a while and got hot. Has been fine (5 or so years) since then. The heating "engineer" called out by my partner wanted to change the whole burner for this fault.

 

[ronan]

Does the pump shaft run on an Oilite bearing? this bearing -which is on the "dry" side of the Danfoss pump's seal needed a good soaking in oil on my 15 or so year old Monoflame burner. This had been blowing the fuse once it had run for a while and got hot. Has been fine (5 or so years) since then. The heating "engineer" called out by my partner wanted to change the whole burner for this fault.

Nope runs direct in the body of the pump, which i reckon is cast iron, it marks very easily. I thought there was a bearing on one side, as there is a circlip and a seal, but it turns out thats all there is.

 

[Turbo]

Those suntec pumps are rubbish, you were lucky to get 22 years from it! I used to service steam washers & the new ones came with suntec pumps that gave loads of bother. We swapped them for danfoss units which lasted for years.

Those pumps rely on the kerosene to lubricate them & only a few seconds of dry running can be enough to cause damage. Check that you have no blockages in the supply side such as filters, some of those pumps have a filter inside. You said you thought the jet was blocked - did you recently get oil delivered or has the tank been disturbed - something might have stirred up the muck in the bottom of the tank & it has got into the fuel lines.

 

[waddycall]

If you change it yourself you’ll need a gauge to set the oil pressure.

 

[julianf]

Photos below. Its picked up a fair few cobwebs and surface rust on the bare surfaces, but i assure you it has never been fitted.

In the bag is the blanking plug that has been removed to fit the brass fitting, and also the small insert thing that you fit (or remove - i can remember which) to change the pump between single feed, and feed and return.

The shaft is a D shaft.

I fitted the brass fitting as, IIRC, the fitting on the burner i was going to use it on was non-standard, so i would have needed to cut the pipe, and use the compression fitting, but i suspect yours will be the same thread, so no need to use the compression.

The burner i was going to fit it to was a 1972 electro oil unit.

 

[ronan]

Thanks julian, but mine is stub mounted , the stub being around the shaft.