Help needed with electrical problem

I've got a commercial espresso machine in my garage. I'm doing it up. The heating element is rated at 6600W @ 230v, so around 27A.

Power goes to the main switch, + goes straight to the element then - goes to a pressurestat which controls the pressure and therefore the temperature in the boiler, then on to the - terminals on the element.

The short question: What reading should I get when testing the resistance of a 2200w element?

The long story:
The machine has a 3 legged element, one bit of kit but split into 3 circuits. I disconnected the negative side of 2 of the circuits to reduce the power to 2200w to run on 13A. This seemed fine and it was in use all weekend without a hitch.
Monday night I was a bit dim. I drained the boiler as described by the manufacturer by switching off the machine at full pressure then opening the hot tap and draining the water this way. I then didn't refill it dickhead. 24 hours later I returned to the machine and found it was still warm and had some residual pressure. I switched it on and everything went dark. I noticed some scorching on the bakelite insulation separating the terminals of the pstat and thought that was knackered.

I bypassed the pstat and wired the element directly to the switch and the element warmed up without tripping the mains. I then replaced the pstat with one I had knocking about and switched it on. The element heated as I watched black scorching creep across the insulation for a minute or two until, once again, everything went dark.

I’m confused. I would have thought the element was effed but wouldn’t it trip the breaker when wired direct? I can’t think why the pstat would suddenly be drawing enough power to burn it out. Any help greatly appreciated.
Ta.

pm Hippy he's mended a few coffee machines

Anyone on here know about installing electric cookers?

Ours is all wired in with colours matched, oven switch is on, fuses look ok, trip switches all on and yet it has no power.

The bit in the manual I'm not clear about is the "The cooker can be connected to the mains only after removing the back panel of the cooker itself with a screwdriver".
http://imagebank.indesitcompany.co.uk/brochures_online/pdf/Hotpoint/Cooking/EW36_EW38_19506050904.pdf

It says "back panel" and not "terminal board" which refers to the plastic box where the wires are screwed into which worries me. Do you actually need to disassemble and mess with cookers internally in this case?

Any electrician types want a quick job?

As far as I know and from reading your manual, the back plate should refer to the terminal block.

Do you know if you actually have power to the leads?

I would either use a non intrusive test screw driver to test for power, any hardware store has these for 2 to 5 quid.

If you dont have that, turn off all the power at the consumer unit, then connect like a side light or anything that you know works to test for power.

ALWAYS TURN OFF THE POWER BEFORE DOING ANYTHING INTRUSIVE.

Sorry for tyhe patronising caps.

Anyone on here know about installing electric cookers?

Ours is all wired in with colours matched, oven switch is on, fuses look ok, trip switches all on and yet it has no power.

The bit in the manual I'm not clear about is the "The cooker can be connected to the mains only after removing the back panel of the cooker itself with a screwdriver".
http://imagebank.indesitcompany.co.uk/brochures_online/pdf/Hotpoint/Cooking/EW36_EW38_19506050904.pdf

It says "back panel" and not "terminal board" which refers to the plastic box where the wires are screwed into which worries me. Do you actually need to disassemble and mess with cookers internally in this case?

Any electrician types want a quick job?

Do you have a multimeter to confirm 240V AC is present between live (brown wire) and earth (green/yellow) on the terminal board? Then you can determine whether it's the cooker or the supply.

Do you know if you actually have power to the leads?

Nup. I'm going to hopefully borrow a multimeter later. Or grab a test screwdriver from somewhere local.

As far as I know and from reading your manual, the back plate should refer to the terminal block.

That's what I figured. I couldn't imagine having to pull down a cooker to install it. Thought maybe there was some DIY-prevention system I don't know about.

I've pulled the cooker out and had another look. What I thought might've been their 'back panel' was just the casing earth screws so I'm thinking now it's lack of power or the unit is faulty.

Thanks very much for your help guys.

ALWAYS TURN OFF THE POWER BEFORE DOING ANYTHING INTRUSIVE.

Sorry for tyhe patronising caps.

No, you're fine, I turn everything off before going near it. My old man was an electrical engineer and met Mum working at the State Electrical Commission. Awwww... :)

Are you connecting it to a dedicated cooker outlet and was there already a lead connected to the outlet or did you have to fit a new lead? Is your fuseboard labelled and does it have any form of RCD protection?

Is it wired through a cooker switch located on a wall somewhere as that may need to be turned on. I used to be an electrician and may be out your way tomorrow as I need to drop something off. Give me a shout if you still have problems and I'll sling my tools in the car and will have a look.

Nup. I'm going to hopefully borrow a multimeter later. Or grab a test screwdriver from somewhere local.

Don't rely on one of those cheap test screwdrivers I have a proper tester rated up to 500v a Fluke multi meter as well as a volt stick if you need to borrow anything.

Are you connecting it to a dedicated cooker outlet and was there already a lead connected to the outlet or did you have to fit a new lead? Is your fuseboard labelled and does it have any form of RCD protection?

There is a big red switch I believe is dedicated oven switch near where the oven sits.
Coming out of the wall is a 3-lead terminal where we've connected a lead that then connects to the oven terminal.

I've just tested a working powerpoint and then test screwdriver lit up but when testing the oven terminals I get nothing. So it appears there's no power to the oven.

None of the electricals are labelled. I assume it's a 30A fuse for the oven but there's 3 of these and they all seem fine. 2 old style wire ones, one normal 'fuse looking' one but all seem fine.

All three of these fuse boxes are switched ON. The big red oven switch is on.

Is it wired through a cooker switch located on a wall somewhere as that may need to be turned on. I used to be an electrician and may be out your way tomorrow as I need to drop something off. Give me a shout if you still have problems and I'll sling my tools in the car and will have a look.

Yep the big red cooker switch is on.

Don't rely on one of those cheap test screwdrivers I have a proper tester rated up to 500v a Fluke multi meter as well as a volt stick if you need to borrow anything.

I know they're a bit shit but it definitely lit up in a normal power point and not in the oven lead.

Did the previous owner have an electric cooker? The fuse is likely to be one of the 30 amp jobbies and, assuming there was a working cooker there previously, hopefully the problem will be fairly simple. I would come a check it out with my meter but a) I'm over the wrong side of London in Kent, b) I've just opened a bottle of falling over liquid, c) I'm cooking dinner in my working oven so sounds like diable's your man. Good luck and I hope it's something simple but sounds like you should start saving (again) for a rewire soon or at the very least a fuseboard upgrade.

Takeaways FTW!

PM me your address and I can take a look at it in the morning if that ok with you.

I'm out racing tomorrow morning. I'll sort something out.

wvm: Yep the space we are using is where the old cooker was. I thought it would be a simple matter of 'join wires, turn on'. Guess not. Balls.

Needs hard wiring?

My guess, blown fuse or disturbed and now broken wire in the cooker outlet - unless you are a total failure and have missed something obvious ;)

Well it might be the tube-style fuse. All the other fuses were the older threaded wire ones and looked intact. I'll see if I can get another fuse for it and try that. It could be something obvious but we'll see.

Could be. What is the rating of the fuse and did the previous owner have an all electric cooker or one with electric oven and gas rings (or even all gas)?
Just thinking that an oven only would require a 13amp suppy whereas yours will need 30amps.

I think the cooker has a ceramic hob.