Humidifier

I do like boy's toys, so I have just installed a humidifier system in my conservatory.


This is the system I have - from Simply Control, garden accessories, horticultural supplies It consists of a humidistat that can be set to the value you want. This is like a thermostat but measures humidity instead.


If the humidity is below the set value a solenoid effectively turns a water tap on. The water at mains pressure is passed to a couple of fine nozzle like the one above. These produce a spray that is so fine that you can hardly see it. And this raises the humidity level.

So far it seems to be working very well. The spray is very fine but it does produce a puddle of water below, so the nozzles need to point where this is not a problem.

I am hoping that this will cut down on watering, as well as keeping the plants happy. At present i have a very high humidity level when the temperature is low, but that drops a lot when it gets hot. And its on the hot days that the plants use most water. I will keep you posted on how it goes.

 

I have just had another look today and everything seems to be working fine.

The biggest disadvantage is the pool of water below the spray heads - but I think that is inevitable and not really a problem having positioned the heads where there is no foliage directly below.

What has pleased me a lot is that after setting the humidity level to 70%, I placed a separate (German made) humidity meter next to the control box and that too read exactly 70%. Whilst temperature measurements should be fairly accurate, I have always assumed that humidity readings weren't.

A further thought has crossed my mind. Its always difficult going away and leaving the watering to friends. However, if I turn the humidity up to 95% and close the doors - I have essentially created a terrarium. Which might mean that I could go away for a week in high summer and not have any need for watering.

 

Close the doors?
This time of year?
The temperature is sure to rise to stupid levels, even though the humidity might be high.

I once closed down my greenhouse on a hot summers day after soaking everything with water, at 50C I bailed out.

 

You are quite right Pete. It did reach over 40C today inside with everything closed - with 70% humidity. Almost impossible to walk in there. Though being Yorkshire the temperatures won't be quite as high as in Kent.

I have been thinking about this and a very easy and cheap solution would be to have a Ventaxia (or similar) to blow air in from outside. There are already some air vents that are always open to let the hot air out. The Ventaxia would have to be run off a thermostat which switched on when the temperature was above the set point rather than below it - such thermostats do exits.

The only problem is that the conservatory is fully double glazed, and its not easy to put a Ventaxia in a double glazed pane - or is it?

 

Assuming that the double glazing is toughened, then I doubt you could fit extractor fans to existing units.
Not sure, but it might be possible to have new units made to accept a extractor.

Which is all going to bump up the price.

Would it not be possible to put the fan in maybe a timber or PVC panel lower down, or even replace one or two of the double glazed units with polycarbonate.
Not sure of the design you have.

 

After writing the above I had a Google, and Vent-axias are pretty common in double glazed windows. There are plenty of places selling kits for about £20 or £25 consisting of the fan and mountings. They say all you need is a couple of holes in your glass unit. But where do you buy holes.

Actually its pretty clear that its not a big deal, and I think I will make some enquiries tomorrow with a double glazing and a glass cutting firm, that I know is not far away.

However, you may be right about being difficult to cut a hole in an existing pane. I know that using a glass cutter on old glass is much more difficult that on new glass.

I also Googled for a temperature controller. A decent one is quite expensive £50 or £60, but they do come with the facility for heating and cooling. I have done with the cheap Chinese ones that last only a short time.

I have also come to the conclusion that it is better to such air out than to blow air in. If air is sucked out, it will be replaced with fresh air coming in through the existing 7 air vents. Whereas air blown in would only come in at one place.

 

I went round to a double glazing company this morning and they said that putting an extractor fan in a double glazed window would not be a problem. But it must be done in a new glass pane (as you suggested Pete), and can't be done in an existing pane. So someone is going to come round next week and give me a quote.

 

A double glazed pane should have a vacuum between the panes. Drilling holes in it would lose the vacuum and reduce the efficiency.

 

You are right LongK, I think double glazed units are sealed units and any hole will break that seal. Having said that its the air gap that gives the insulation and that will still be there. Strictly speaking I think there is an inert gas inside rather than a vacuum. But once the seal is broken moisture and mould could enter.

However, having Googled, extractor fans seem to be pretty common in double glazed units. I will learn more this afternoon when a chap is coming to look at it and measure up.

 

If they make a new unit with the hole already cut in both panes along with spacer bar around the hole I cant see a problem.

 

Hi @PeterS your double glazing normally just has dehydrated air in it (they put silica gel I think behind those pinholes in the metal sheet you can see round the edge). That's why when your seal goes, the main effect is the moisture build up between the panes.
Fancier double glazing has inert gas in the space inside. BUt if the supplier puts the unit in, then provided they seal it properly, the gap will be dehydrated and the insulation will stay effective (apart from the fact that the fan unit can't be very effectively sealed in cold conditions because those covering flaps are never that good, so there will be a draft...)

 

I think I have finally cracked the problem - though I don't have all the bits yet. I did have to do quite a bit of digging - there was no-one to explain it. The double glazing chap said that he would sell me a hole, but wouldn't have anything to do with the extractor fan. The next place I went to sold extractor fans, but didn't know anything about fitting them. The next place was very helpful, and I finally bought the bits from there, but they didn't know anything about fitting them, and even after reading the instruction in the fitting kit and ringing up the manufacturer - still couldn't tell me.


Looking at the fitting kit and two display units in the shop, I realised that there two different types of extractor fan. One for walls, with a plain bit of tube at the back, and one for windows with a threaded tube as above. The first type screws directly into the wall, but the one for a window needs an extra fitting kit, which consists of two thickness of spacer and a threaded ring, plus a few extra bits. The threaded tube is pushed through the hole in the glass and the thick spacer is used outside for a single pane, and the thin spacer is used for a double glazed pane. The threaded ring is then tightened to hold the unit in place. - simples .

 

But will your double glazing chap seal around the hole he makes, so that the air between the panes doesn't get moisture? Otherwise you will see nasty condensation between the panes.

 

If he doesn't it will not be a double glazed unit as such.
I seriously doubt any reputable glazier would sell a double glazed unit that is not sealed.

Most of the units I come across are argon filled, you can tell if the spacer bar has two round holes, one to suck the air out and one to pump the gas in.