Danfoss solenoid coil

[Nostrum]

Noticed there are 3 pins on the connector plug. Attended a break down today which I don't normally do for oil and wondered if they are all used, if so what are they? Live neutral and . . .

the breakdown was no oil to nozzle, used solenoid tester and not energising, photocell seems good, get 240v onto coil but prior to that as pump etc is running and its going through the motions I'm getting a fluctuating voltage of about 35v, any ideas?

140psi at pump, just wondering if its the coil or control box because of this stray voltage prior?

Was dark by the time I left any raining so packed up quick ordering both parts just in case, now I'm doubting myself, also forgot to measure coil resistance, what should it be.

cheers in advance

 

[lame plumber]

coil or solenoid stem could be issue, voltage issue due to induction off coil ? or as you say control box, Id try coil, stem control box in that order. have fun.

 

[Nostrum]

Didn't have any reason to suspect stem as couldn't energise coil, presuming my solenoid tester is going to light up with it stuck through the middle? If it doesn't I just as well chuck the thing!

whats the third contact for on the coil, not earth is it? Or is it? I was struggling like mad with a torch and my hood up in the rain come the end. By the time I'd removed burner and checked spark etc and refitted it was dark.

 

[lame plumber]

coil contacts only normally 2 so third, for soft start on twin coil ? not sure

 

[SimonG]

Don't know why it's three pin as it's only two wires.

I'm still wanting to make up a test rig for coils in the garage.

Coils, stems and control boxes are always on the van. For both riello and danfoss/satronic gear. A 90w and 70w motor, couple of danfoss oil pumps left handed plus a right handed for the trianco's. RDB and mectron motor, photo cells Mz770, riello long & short and a mectron one.

Costs a bit to carry but saves money in the long run.

 

[Nostrum]

Company I'm contracting to don't have any oil stock on van, it was only when they found out I had the tickets they started taking it on, sending me down the bum end of Cornwall to attend a contract breakdown on a Saturday. Not even a oil pressure gauge until I flagged up I needed one!

 

[SimonG]

Company I'm contracting to don't have any oil stock on van, it was only when they found out I had the tickets they started taking it on, sending me down the bum end of Cornwall to attend a contract breakdown on a Saturday. Not even a oil pressure gauge until I flagged up I needed one!

Ah can't beat being handed the brown end of the stick.

 

[lame plumber]

Don't know why it's three pin as it's only two wires.

I'm still wanting to make up a test rig for coils in the garage.

Coils, stems and control boxes are always on the van. For both riello and danfoss/satronic gear. A 90w and 70w motor, couple of danfoss oil pumps left handed plus a right handed for the trianco's. RDB and mectron motor, photo cells Mz770, riello long & short and a mectron one.

Costs a bit to carry but saves money in the long run.

cant have to much when your in the middle of nowhere! Ive got several of the hwos boxes with, control boxes,filters,photocells,ignitors,pumps etc need some motors but out of readies now due to being off work 3 months. I hate to think of the value of all that and as well as nozzles lines etc. Had to laugh at abcos engineers spares packs, not priced in the catalogue they send out, 5 of everything !!!!!!!!!!!!

 

[SimonG]

It's about 200 - 250 in nozzles alone, and that's cost.

 

[Bunker]

I have at least 2 of each and every nozzle but 4 of the more common ones, they are arranged in a sorting case (the type for screws) and in numeric order (.4 up to 1.1) so when re-ordering I can see at a glance whats needed. Old nozzles go in my brass waste box for weighing in (they soon add up!). I also have a Danfoss nozzle box with all the bigger S's and H's in and another one with all the W's. I carry 2 each of the common motors and pumps (tried those universal Delta ones - awful!) - and of course loads of control boxes, electrodes, photocells etc. I recently bought one of each of the PRVs from HWOS and a few AAVs (and 1/2" nipples).
The hoses get me though, there's 3/8 and 1/4, male and female - so many combinations possible - is it best to just carry a few but a box of adaptors? What do you guys do?

 

[SimonG]

Only carry a couple of hoses and then I have a stanley organiser box with all my 10mm fittings and bushes and adaptors etc.

 

[lame plumber]

carried loads of hoses at start but now i tend to go for several of elbow onto pump and female 3/8 and use nipples to adapt

 

[kimbo]

whats the third contact for on the coil, not earth is it? Or is it? I was struggling like mad with a torch and my hood up in the rain come the end. By the time I'd removed burner and checked spark etc and refitted it was dark.

The third is earth, quite frequently the coil can go and go to earth which trips out the electrics
How do you know the photocell is ok?
There is an easy check for this
An easy check of the solenoid is put a screwdriver in it with it off the pump, when it is energised the screwdriver is held in the coil.

 

[lame plumber]

hes got a posh solenoid tester, which are great till the batteries go flat and you dont check first, like i had recently and u revert to screwdrivers! wondered what the 3rd spade was.

 

[Nostrum]

Hi kimbo,

open circuit in dark and low res in light on the photocell. Will the control box still send power to the coil if the photocell is not satisfied (darkness) first?

 

[Bunker]

Solenoid testing is a bit hit n miss as they mostly fail when hot. If i suspect it, I'll stick a new one on, I find that quicker. In the odd occasion where that was wrong, ill change back and stick it back in the box obviously without charging for it.

 

[Nostrum]

Hi bunker,

this was DOA. Gonna need to carry some spares at least if they are going to profit off these. It's going to mean another trip down there now. 2hrs of travel plus time to do job plus getting back to my usual patch, fuel, wages. I know what they earn off it and it ain't going to cover that.

 

[Nostrum]

Also kimbo. Just adding to my previous post, surely if the photocell was playing up it wouldn't spark, or it would fire but then lock out if I understand the sequence correctly?

 

[kimbo]

Hi kimbo,

open circuit in dark and low res in light on the photocell. Will the control box still send power to the coil if the photocell is not satisfied (darkness) first?

You haven't explained exactly at what stage the burner locks out which is usually a clue where the problem may be. You should hear a click when the solenoid is energised. The control box will not send power to the solenoid if the photocell is not confirming no light unless it is faulty. An easy check is to disconnect photocell and fire the boiler, if the burner fires up and then goes to lockout the cell is faulty.

 

[Nostrum]

Sorry thought I had explained on first post. No oil to nozzle, boiler sparking but nozzle bone dry. Pump pressure good and oil in pump is o.k. 240v onto coil but with no click, although a strange rapidly fluctuating voltage of approx 35v prior to this.

im pretty comfortable with the operation procedure I think, been doing oil for about 5 years but haven't come across much in the way of variety as a lot of it was installation and servicing boilers I have previously fitted so it was all fairly new and Worcester. Do they all follow the same procedure or are som slightly different in any way?

 

[lame plumber]

no click could be coil esp as its not enregised but as stated check photo cell as described by kimbo who described operation perfectly.

 

[Nostrum]

Sorry, how can it be the photocell if there is no oil on the nozzle but has strong spark?

kimbo, if I am correct, you mention testing the photocell by removing, this is because control box is looking for open circuit or very high resistance to prove darkness, yep? So once the boiler fires and the resistance does not drop the boiler see's there is no ignition and locks out? About 5-7 seconds?

A problem with the photocell would cause an open circuit which would prevent the boiler getting to ignition and as far as the control box is concerned, open circuit is light, therefore locking out before attempting to fire/ignition.

Edit: this above is wrong, serves me right for staying up late. Open circuit would indicate darkness, so the boiler will fire but will lock out as it will not detect ignition!

Cheers in advance

 

[lame plumber]

if the pc is faulty, removing it will allow burner to fire for short while and then lock out. as you have described above. if you then try with pc connected and it wont fire pc proved faulty

 

[kimbo]

What burner is it and I presume you have changed the nozzle, that would be the first thing to do before carrying on. The only sure way of checking the pc is with a Lux meter and sometimes resistance other than the way I have described.

 

[Nostrum]

No nozzle changed, as described I carry no stock whatsoever although I have ordered the correct one with the parts as the nozzle was black. That said, would a nozzle just completely fail overnight allowing no oil to pass at all and the end of the nozzle be bone dry? Possibly but then should still hear the solenoid clunk?

i'd be interested to hear how you can test a photocell using a lux meter without measuring its resistance. I do have a lux meter which I used when installing solar P.V.

I am not in a position to be able to carry a spare of every component to swap out if I suspect it faulty, so I will need to be able to confirm the fault by way of testing, hence the original question. It sounds like having the parts on the van is the most common way of fault finding when it comes to oil boilers.