How hot is it in your observatory?

[glend (Glen)]

I just saw 49.3C in my observatory (it's 42C outside in the shade right now). Even with the solar exhaust fan buzzing away madly the temperature can't be held down to ambient. I've had to prop the door open to try and get better air exchange. I don't keep anything that can easily be moved in the observatory during the summer for this reason. All that's sitting out there is the NEQ6 mount head on the pier, all the other gear is in a box in my air con'd study. I won't leave cables, controllers, PCs, etc out there in this heat.
What are the temps like in yours and what do you do about heat management in the summer?

[clive milne]

Originally Posted by glend

what do you do about heat management in the summer?

https://www.danmurphys.com.au/media/...9854672873.png

[Terry B]

Mine gets hot as well. Doesn't seem to do any harm. The scope won't melt.

[sl]

I kept my roll-off roof observatory cooler by painting the outside white (helped a lot more than I thought it would) and lining the inside with styrofoam panels. You can't keep it cooler than the air temperature, but it's no longer an oven.

- Steve

[loc46south (Geoffrey)]

Hi - When I built my observatory I put in a raised wooden slat floor with 5mm gaps between boards (just enough to drop small screws through) - the floor is a minimum of 300mm off the ground.

With the roof rolled over it acts like an old fashioned meat safe and the warmer roof draws colder air up from underneath the building - on a hot day it will be 5 to 10 degrees cooler in the telescope room than outside.

This is a byproduct of the main reason - the observatory is situated on top of an exposed ridge and the floor is designed to equalize air pressure inside the building in high winds and reduce the risk of losing the roof.

Cheers
Geof Wingham

[hamptonskies (Greg Burrows)]

I painted my domes with Solacoat. The domes are clad with galvanised steel sheet. Solacoat is a special paint used on roofs which is highly reflective. Even under the summer sun the surface is cool to the touch as it doesn't retain any heat. It is expensive but does an amazing job. My observatory walls are made of brick which a lot of people disapprove of as it retains heat, but the Solacoat works great on the bricks as well.

[sheeny (Al)]

Mine typically maxes out at about 40°C. Due to altitude I'm typically 7°C cooler than you would be on the coast.

I have a solar ventilator in the top of the dome. Prior to installing that I used to get max temps up in the mid to high 40s.

My max min thermometer inside the obs (which hasn't been reset for about 12 months) currently shows 41°C.

I believe from my electrical engineering friends that about 40°C is the limit for reliability in electronic gear.

Al.

[Paul Haese]

Last couple of days the remote obs have been sitting in temps of above 41 degrees C during the day and temps in the mid 20's at night. Inside each observatory the temps have been in the high 40's. Both observatories have endured these temps for several periods during summers for the last few years since I began operating remotely. That includes computers, UPS, scopes, mounts etc. No effects have been observed so far in regard to heat. That said, I don't operate the cameras in those temperatures and wait until I can open the shutters before starting the cameras. Sitting idle in such temperatures should not affect any equipment you might have in your observatory.

[GrampianStars (Rob)]

Originally Posted by loc46south

Hi - When I built my observatory I put in a raised wooden slat floor with 5mm gaps between boards (just enough to drop small screws through) - the floor is a minimum of 300mm off the ground.

With the roof rolled over it acts like an old fashioned meat safe and the warmer roof draws colder air up from underneath the building - on a hot day it will be 5 to 10 degrees cooler in the telescope room than outside.
....
Cheers
Geof Wingham

Similar here though only a 2mm gap
even in high heat 46C the temp inside is only around 38C

[Nortilus (Josh)]

I'm planning to do a Absco Pool pump shed obs and I have also read about this Solarcoat paint. I am just going to get the plain galvo unpainted shed and coat it with this stuff. I am also going to line the inside with that silver insulating stuff and seal the inside with thin plyboard.
I will then add a solar powered extraction fan somewhere high up and an intake vent down low so that there is a nice constant flow of air running though the obs. Hopefully that will help reduce moisture buildup too. Might put some kind of dehumidifier in there too. Even just one of those moisture traps you put in your cupboards

[peter_4059 (Peter)]

Hey Josh - let me know how you go with the lining and the solar fan. I've ordered my Absco shed and I'm just waiting for it to get delivered now. I'm also considering some foam lining but haven't found anything suitable in small quantities yet. I'll probably go to the boat shop for the fan as the ones at Bunnings/Masters are quite large. Not sure how they will go fitting to the roof panel profile yet.

[Nortilus (Josh)]

Peter, for a fan im just going to use 12V PC case fan. You can get 200mm high pressure ones for about $20. Then a simple solar panel kit with rechargeable battery setup.

[hamptonskies (Greg Burrows)]

One comment about Solacoat, I found the best way to apply it was by roller. Tried using brush but found it hard to give a consistent coat. The tradies mainly use spray gear for applying it.
Another feature is that it cleans up great. After a few years my domes were a bit dirty from being in the middle of a field but after washing them down with a sponge mop they came back all shiny again.
Greg

[DavidTrap (David)]

The walls of my observatory are 4 inch thick freezer panels - always quite cool. They don't seem to have much thermal mass, so it cools down quickly at night.

DT

[PeterM]

I use this at my home shed observatory. Redo it every 3-5 yrs and seems to keep temp in check. Bunnings sell it. See specs re temperature.
http://www.pscoop.com.au/newweb/msds...lvershield.pdf