Elevation measurement with 235?

With GLONASS and GPS enabled the elevation should be within about 10m. There's no barometric altimeter in the watch.

As far as I know, the 235 does not have a built in barometer and is using GPS data to show the elevation level, which is not that accurate if your changing your position while checking on your elevation.

Hi,

Is the 235 supposed to have an accurate elevation measurement?

No. Only the higher-end devices have proper barometric altitude. The 235 is a midrange (despite the price) runner's watch, and uses positioning system data to work out elevation.

(You can pick up a 920XT for less than a 235, which does have a barometer..)

Edit:

Wow, so my information is out of date- things change a lot in a week.

It seems that prices are becoming more sane, the 235 has dropped about £50, and the 920 has risen in price a bit. I paid £259 for the 920 with an HRM recently, which was a pretty good deal- now they're over 300. On the upside, the 235 isn't as insanely expensive as it was, for people brave enough to buy one :)

With GLONASS and GPS enabled the elevation should be within about 10m. There's no barometric altimeter in the watch.

GPS elevation (vertical) accuracy can be substantially worse than it's horizontal accuracy. This is due to the physics/geometry of where the satellites are that the device can "see"; Mr. Google can lead you to a more technical discussion of the details if you're curious, but here are a couple bits to start with.
https://support.garmin.com/support/searchSupport/case.faces?caseId=%7B66f1b0a0-4cd6-11dc-4733-000000000000%7D
http://www.dcrainmaker.com/2010/05/understanding-sport-device-gps.html