Can Honeywell vt200 TRV be calibrated?

[mephisto]

I've installed Honeywell vt200 TRVs on most of the radiators in the house and given them a brief test. Everything seems to work okay but there does seem to be some variation in temperature sensitivity - not totally unexpected as I realize these aren't scientific instruments.

The instruction sheet that came in the box appears to show some kind of calibration or adjustment but I can't make out what it's referring to as it's just a picture.

Here's the instructions (pdf):
http://www.honeywelluk.com/Documents/Full-Install/pdf/946.pdf

Step 7 "Site Calibration" apparently shows the valve head opened up and something adjusted to 12mm. What is this? I can't see an easy way of opening the valve heads I've got as the plastic parts are snapped together quite firmly.

Thanks.

 

[ALEC1]

12 mm will be the margin for calibration...it sounds like a lot of aggro to me...just run some at the number you are comfortable with...


I would be sure that they do come to pieces..you just have to know now...

 

[D_Hailsham]

I've installed Honeywell vt200 TRVs on most of the radiators in the house and given them a brief test. Everything seems to work okay but there does seem to be some variation in temperature sensitivity - not totally unexpected as I realize these aren't scientific instruments.

The instruction sheet that came in the box appears to show some kind of calibration or adjustment but I can't make out what it's referring to as it's just a picture.

No mention of "calibration" in this version of the Installation Instructions. (It's from the same web-site!)

It looks more like an assembly dimension than an instruction for adjustment in the field.

Your variation in sensitivity could be due to incorrect balancing. Read How to balance a CH system.