Can I use 16V ~1000ma power supply to power an aplliance that requires a 14V ~800ma power supply nomally? I have been told that it should be possible and not create any problems. Please help the lead I require will not be here in time and I need something to do the job immidieately! Thank you for you help.

Well its working!! But I hope I'm not doing any long term damage?

It depends a lot on what the item is that you're powering. Usually, if a DC circuit is made to use 14V, its individual components will be rated for something a little higher than that. It's also possible, especially if it's something really sensitive, that it will have an internal voltage regulator to knock the voltage down to something lower (and more consistent) within the circuit. In that case, the voltage regulator will have to dissipate a little more power, so it'll run a little hotter. If it's something that requires air circulation to remain cool, you'll need to be extra careful that you keep it out in the open and cool enough.

If it's an AC supply, the item almost certainly has a rectifier and voltage regulator. The same thing applies; the regulator will be dissipating more power, so you'll need to make extra sure that it has adequate ventilation to keep cool.

For what it's worth, the 1000mA current rating should be more than sufficient (any extra is fine; the circuit will only draw as much as it needs).

As far as long term damage goes, it's possible that you're slightly shortening the lifetime of the item. That doesn't mean that it'll die tomorrow; it just means that the expected lifetime may be slightly shorter. If this is just a short-term fix until you get the necessary lead in a week or two, I doubt it'll have any substantial long-term impact. However, as I said before, it depends a LOT on what exactly it is that you're powering.

http://www.smpstroubleshooting.com/