Water on roof cooling

[Ray T]

2 hours ago, IanD said:

 

Phwooaaah, proper old technology -- just look at the selectors on that... 🙂

 

When as a "Youth in training" with the G.P.O. I had to do time in various telephone exchanges, most were post 2000 type equipment but one, "Gibbet Hill," (I think the 1141 code was GTL) was pre 2000 selectors. On my 18th birthday I had been out to lunch with some of the other Youths and arrived back at the exchange somewhat worse for wear. The TO in charge, one Ray White, was not amused at all. My "punishment" was manual bank cleaning of the 2 motion selectors for the next 2 weeks, was I bored!

 

I always disliked working in a telephone exchange, much preferred the "external side" of the business.

 

Sorry, off topic!

 

 

Edited June 16, 2023 by Ray T

[Tam & Di]

Not exactly as large as a boat, but Osokool 'fridges' work very well. For any who may not know them they are a small metal box with frontal door, totally covered in a water-absorbent chalky material. There is a shallow saucer in the top which you fill periodically with water, the evaporation of which keeps the interior of the box cool. We used to keep vegetables and such in a basket on the deck, covered in a damp towel. For it to work you need to let the towel get more or less dry before dampening it again.

 

Tam

[captain flint]

2 minutes ago, Tam & Di said:

Not exactly as large as a boat, but Osokool 'fridges' work very well. For any who may not know them they are a small metal box with frontal door, totally covered in a water-absorbent chalky material. There is a shallow saucer in the top which you fill periodically with water, the evaporation of which keeps the interior of the box cool. We used to keep vegetables and such in a basket on the deck, covered in a damp towel. For it to work you need to let the towel get more or less dry before dampening it again.

 

Tam

Yeah this is basically a version of the classic camp fridge, a bowl of water, a cloth tent with the end in the water. Evaporation = cooling, and wicking draws more water into the cloth to keep it damp. As said earlier in the thread, doing that on a giant scale over a boat, with a damp sheet just proud of the roof, with the ends in the water, would quite probably/almost certainly make quite a significant difference. But not very easy. Huge sheets required. Then you'd need to store them. 

 

But maybe worth investigating, I suppose. I did see a boat with a sheet draped over it the other day, though its ends weren't in the water

[ditchcrawler]

9 minutes ago, captain flint said:

Yeah this is basically a version of the classic camp fridge, a bowl of water, a cloth tent with the end in the water. Evaporation = cooling, and wicking draws more water into the cloth to keep it damp. As said earlier in the thread, doing that on a giant scale over a boat, with a damp sheet just proud of the roof, with the ends in the water, would quite probably/almost certainly make quite a significant difference. But not very easy. Huge sheets required. Then you'd need to store them. 

 

But maybe worth investigating, I suppose. I did see a boat with a sheet draped over it the other day, though its ends weren't in the water

I saw a boat rigged with sheet in a similar fashion a few years back 

 

[captain flint]

13 minutes ago, ditchcrawler said:

I saw a boat rigged with sheet in a similar fashion a few years back 

 

Yeah, if we continue having these baking hot summers, I might look into it. I have some old tin steamer trunk type things I could dot along the roof and drape sheets/dustsheets over. Heck, if I clear them out I might even have somewhere to store the sheets... 

[Alway Swilby]

6 hours ago, Ray T said:

 

Was that pre 2000 Strowger telephone exchanges?  😁

A opps B opps C...... cannot remember the rest

I seem to remember that it was A operates B and the rest is automatic.

[IanD]

21 hours ago, captain flint said:

Yeah this is basically a version of the classic camp fridge, a bowl of water, a cloth tent with the end in the water. Evaporation = cooling, and wicking draws more water into the cloth to keep it damp. As said earlier in the thread, doing that on a giant scale over a boat, with a damp sheet just proud of the roof, with the ends in the water, would quite probably/almost certainly make quite a significant difference. But not very easy. Huge sheets required. Then you'd need to store them. 

 

But maybe worth investigating, I suppose. I did see a boat with a sheet draped over it the other day, though its ends weren't in the water

Worked pretty well for the beer last weekend when it was 30C, using a hose to keep the towels wet...

[Stroudwater1]

Someone I know in the marina did this last year. He was a high powered engineer. He seemed to think it worked reasonably well but he wasn’t over the moon with it. 

I got the impression it was a case in part of justification of the hassle of setting it up. The end result was impressive to look at but perhaps less impressive at keeping occupants cool. 

He offered some of the hoses to another friend during the Wimter and I imagine if an outstanding success that wouldn’t have happened? 

[Alan de Enfield]

1 hour ago, Stroudwater1 said:

He offered some of the hoses to another friend during the Wimter and I imagine if an outstanding success that wouldn’t have happened? 

 

Did he really expect an outstanding success trying to cool the boat with water in Wimter ?

Why would you even try ?

[Stroudwater1]

14 hours ago, Alan de Enfield said:

 

Did he really expect an outstanding success trying to cool the boat with water in Wimter ?

Why would you even try ?

He gave the hoses away during this last  Winter so he won’t be able to use them for the same method again this Sunmer Alan.
 

It was a loan of hoses (needed for drainage of an engines cooling system) by get rid of situation. 

[nb Innisfree]

In 2005 during a very hot spell we moored up next to a white (steel) narrowboat, I couldn't bear to lay my hand on our dark(ish) green roof for more than a couple of secs for fear of burning, I could have fried an egg on it, literally. Doing the same to the white boat felt cool to the touch, amazing difference, though I didn't like the looks of a pure white nb! 

[Bee]

With a selection of shafts, poles and string with a couple of old sheets I made a fairly effective shade over Bee a couple of years ago when tied in somewhere v. hot in France. Worked quite well until a gust of wind blew the lot overboard at 3 a.m. Bee is made for heat with every window and roof light openable and doors everywhere but the only thing that really works is shade from trees.  Bee's cabin sides and wheelhouse roof are white and the roof and decks are light grey, can't imagine the heat in a dark coloured boat.

Edited June 18, 2023 by Bee