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?

Thanks,

Mike

A little spray of WD40 should do the trick.

I have tried WD40, but perhaps I didn't quite hit the spot. Do these things last forever, then?

Mike

On Fri, 20 Feb 2009 21:12:48 +0000, beccabunga
wrote:


drmrbrewer;830831 Wrote:
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?

Thanks,

Mike

A little spray of WD40 should do the trick.

You need to put it on the vent hinges too, because they often get
gunged up and stiff.

"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.

Steve

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

"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

"drmrbrewer" wrote ...

beccabunga;830832 Wrote:
A little spray of WD40 should do the trick.


I have tried WD40, but perhaps I didn't quite hit the spot. Do these
things last forever, then?


Depends on how good they were to start with, the good ones are expensive but
do last a very long time. Doubt you would find them at any GC, you would
need to shop at a specialist.
You mentioned a black cylinder, I think those are some of the cheaper ones
and I've had a problem with them in the past where, after only a few years,
they got weaker and weaker and slower and slower at opening, presumably the
oil leaks out.
Nothing lasts for ever though.

--
Regards
Bob Hobden

On 20/2/09 23:18, in article , "K"
wrote:

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.

Ours are opened every day except in really freezing conditions. As you say,
it soon gets very warm in a greenhouse. One of ours got up to about 25C the
other day.
--
Sacha

drmrbrewer wrote:

I have tried WD40, but perhaps I didn't quite hit the spot. Do these
things last forever, then?

What's in the cylinder is paraffin (the wax, not the liquid fuel; my
American-English dictionary isn't up to date), and they don't last forever.
You should be able to get just the cylinder as a replacement part.


Gary Woods AKA K2AHC- PGP key on request, or at home.earthlink.net/~garygarlic
Zone 5/6 in upstate New York, 1420' elevation. NY WO G

In article , drmrbrewer.414ca98
@gardenbanter.co.uk says...

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?

The black piston won't take kindly to being frozen, I always take mine
out every year and keep them in the house. As for WD, it's not a good
lubricant, use 3 in 1 or similar on the hinges and all moving parts.
How long they last depends, mine are at least ten or fifteen years old.

"pb" wrote
The black piston won't take kindly to being frozen, I always take mine
out every year and keep them in the house. As for WD, it's not a good
lubricant, use 3 in 1 or similar on the hinges and all moving parts.
How long they last depends, mine are at least ten or fifteen years old.

Quite agree about WD40, it is good at banishing damp and at creeping into
places but will evaporate quickly, so if I want to lubricate something I
apply some proper oil (engine oil) and then the WD40 which takes the oil
into the places it would not normally get.

--
Regards
Bob Hobden

Thanks for all the advice. I had a closer look today and took a couple apart. There are indeed a couple which have no resistance left in them, so I assume the wax has all gone. On another couple, the securing nut which holds the threaded part close to the black cylinder has seized up. I think I should be able to turn the black cylinder to adjust its position, but the thread is seized up. No amount of WD40 and brute force will shift it. There are some others that turn easily.

So it seems that some replacement is necessary. Are these standard parts... Will a replacemenet cylinder fit with my existing openers, or do I just buy a complete replacement? I may not be able to extract some of the cylinders from the holding nut/collar which as I said before has fused itself around the threaded part.

I also have several louvre openers that have seen better days, so that they are locked open.

Or perhaps I should just do it manually...

Mike

http://www.greenhousebits.com/search...c+Vent+Openers