Myson Velaire Vitesse blowing fuse

[Martin pawsey]

Hi all
Have a Myson Velaire Vitesse which was installed new in 1992
Been serviced on and off and besides a new pump 5 years ago has worked fine. this morning I noticed the power to it was dead as no lights on the control unit. Checked fuse and was blown. Put a new fuse in and it started the purge programme straight away but when it went to fire up it blew the fuse again. I had a new burner control unit that attaches to the burner so swapped them out, replaced fuse but same again. Runs purge then when goes to fire blows fuse.
it’s minus 4 here and can’t get an engineer for ages so any ideas as to what the issue could be?
Thanks in advance
Martin

 

[oilhead]

Odds on the oil pump solenoid coil. Disconnect it and try starting the burner. It should purge, then go to lockout if the coil is the cause. I'm assuming you still have the original inter burner.

 

[Martin pawsey]

Odds on the oil pump solenoid coil. Disconnect it and try starting the burner. It should purge, then go to lockout if the coil is the cause. I'm assuming you still have the original inter burner.

Many thanks. The burner is original
There is a crack on the solenoid and the nut just spins on the shaft

 

[BoilerBob]

That’s the prob. Bob

 

[Martin pawsey]

That’s the prob. Bob

Fingers crossed. Oil line decided to split as well as I moved the burner out. Hopefully pick both up to orrow in town

 

[oilhead]

It's amazing how inflexible flexible hoses become when they lie undisturbed. Have you managed to loosen the nut on the solenoid or did the whole stem come out?

 

[Martin pawsey]

It's amazing how inflexible flexible hoses become when they lie undisturbed. Have you managed to loosen the nut on the solenoid or did the whole stem come out?

Hi Oilman
Picked up a new flexible hose and solenoid coil in town plus had to get a new immersion heater as wondered why the old one wasn’t heating the water while the boiler was off. Took plastic cap off and all terminals fell apart and started leaking (I thought it’s going to be one of those jobs)
Didn’t think the old immersion was going to unwind butluckily it went. New one fitted and working.
Got old flexible hose off oil filter nice and easy and fitted to pump. Couldn’t get a direct replacement for the suntec one so took a chance on a Danfoss one which fitted Ok. put everything back together and it fired up fine except oil coming from the solenoid shaft. Stripped it down, old washer flat so luckily had a new one the same size. Put back fired up again and now lots of hot water and central heating...
Thanks for your help

 

[oilhead]

Just be aware, you really need to get it recommissioned as the pressure will not be set. If a new Danfoss pump, it will be set at 10 bar (150psi), which is probably 30 psi more than you want. Watch out for plumes of smoke.

 

[Martin pawsey]

Just be aware, you really need to get it recommissioned as the pressure will not be set. If a new Danfoss pump, it will be set at 10 bar (150psi), which is probably 30 psi more than you want. Watch out for plumes of smoke.

I didn’t change the pump just the solenoid coil so pump as before