"K" wrote in message
news
shazzbat writes

"drmrbrewer" wrote in message
...

We've inherited a very nice greenhouse from the previous owners of our
house, fitted out a few years back to a pretty high standard. However,
the automatic vent openers no longer seem to operate as they should,
mostly stuck closed.

I can't find any information as to how to maintain these, and whether I
just need a replacement black piston thingy (and if so, what I do to
replace it), or whether I need to replace the whole mechanism including
the arms etc, or whether in fact it is possible that some simple
adjustment would do the trick. How long do these things normally
last?


How have you ascertained that they're not working? They are thermally
operated, and I doubt if anywhere in UK has been warm enough to open them
for some time now.

My father's were open in Leeds earlier this week.

With a bit of sunshine, the temperature inside a greenhouse soon rises.
--
Kay

Mine were in Wirral too!
I would suggest taking the working body out by unscrewing it, putting it
somewhere warm until it opens fully, and polishing the rod with 3 in 1 oil
or similar - gun oil if you can get it. Remember and note the number of
turns because that is the adjustment.

Whilst the opener is in bits you can check the hinges, if they are too
sticky wet them with diesel oil first.

If the working bit doesnt open you can get replacements from the greenhouse
people.

John