Cooling down my water tank

[Andrew Dwyer]

I have a water tank ( DOS 700 litres ) that gets direct sunshine in the morning for a couple of hours and then from 3 pm to 6pm when the sun drops. This last week has been very hot ( 43c today ) and leaves me with 700 litres of hot water !!

I just retired to the bedroom and took a shower, as usual, but instead of a cool refreshing shower I got a hotter than I would like shower and it set me thinking.

 

Is there any material I could wrap round the tank to deflect the sun, am thinking along the lines of the silver reflective stuff used in roof insulation. ??

 

The tank is tucked away round the side of the house and not in plain sight so appearance is not a problem.

 

No way to use trees for shade.

 

 

[Expattaff1308]

Erect a roof over it to protect it from the sun

[Andrew Dwyer]

Erect a roof over it to protect it from the sun

Wish it was that easy.

From the photo you can see it’s protected from rain but during the morning the sun comes from the right ( which is not a great problem as it only hits a bit of it ) .

The main issue is from 3.00/3.30 pm the sun is hitting it from where i took this photo and continues as the sun drops down heating it from top to bottom !!

[darksidedog]

Interesting. When I was working in Dubai, you couldn't take a cold shower, with water flowing through the mains as it was approaching scalding temperatures in summer. The "hot water" cistern in the roof (with very good insulation) with the power turned off was about 20 degrees cooler. Hot is cold. Cold is hot. Landlord had to explain that two times before I got it.

Shading the tank will help, but given the ambient temperature right now, not much less than a few big chunks of ice in there half an hour before your shower is going to be much help.

Pray for rain and cooler days.

 

[Andrew Dwyer]

Interesting. When I was working in Dubai, you couldn't take a cold shower, with water flowing through the mains as it was approaching scalding temperatures in summer. The "hot water" cistern in the roof (with very good insulation) with the power turned off was about 20 degrees cooler. Hot is cold. Cold is hot. Landlord had to explain that two times before I got it.
Shading the tank will help, but given the ambient temperature right now, not much less than a few big chunks of ice in there half an hour before your shower is going to be much help.
Pray for rain and cooler days.
 

Yes, probably will get cooler soon and it will be forgotten, it threatens to rain every day but never does . [emoji20]

[sometimewoodworker]

1 hour ago, Andrew Dwyer said:

Is there any material I could wrap round the tank to deflect the sun, am thinking along the lines of the silver reflective stuff used in roof insulation. ??

I'm  surprise but nobody suggested the correct answer. All you need to do is to wrap it in the radiant barrier film that is usually put underneath the tiles in the roof. It's very inexpensive about 2000 Bart for 72 m. 

 

It's not going to cool the water down but it will stop the water tank gaining heat from the Sun it won't look pretty but you say pretty isn't a problem.  You won't need to provide any gap between the radiant barrier and the tank itself as if you're going to get any radiation it's going to be from the warm water to the slightly cooler air the Sun is not going to heat the water tank up very much if you use that. 

Edited May 3, 2019 by sometimewoodworker

[Andrew Dwyer]

I'm  surprise but nobody suggested the correct answer. All you need to do is to wrap it in the radiant barrier film that is usually put underneath the tiles in the roof. It's very inexpensive about 2000 Bart for 72 m. 
 
It's not going to cool the water down but it will stop the water tank gaining heat from the Sun it won't look pretty but you say pretty isn't a problem.  You won't need to provide any gap between the radiant barrier and the tank itself as if you're going to get any radiation it's going to be from the warm water to the slightly cooler air the Sun is not going to heat the water tank up very much if you use that. 

Thanks, yes that is exactly the thing I’m thinking of !!
As it’s relatively cheap I can buy some and give it a go.

I think it comes in different thicknesses so will take a look at my local Home Mart to see what’s available .

[tifino]

and employing undergarden piping and circulation, for temperature equalising, would be an expensive exercise

This could only be justified if you used it concurrently for an alternative method of cooling the house too...

[NanLaew]

Just needs shade from direct afternoon sunlight. Sheet of 15mm plywood 244 x 122 (or 250 x 125) attached to/suspended from the air-conditioner condenser unit bracket. Maybe about 700 baht?

 

Paint it white (optional).

Edited May 3, 2019 by NanLaew

[anderstse]

anyone know of electric showers that cool the water,

they all just heat that I have seen. but surely there is one that could cool the water as it comes out of the shower head.

 

or anyone come across any ice bath type cryo genics bath or stand in baths?

[sometimewoodworker]

7 hours ago, Andrew Dwyer said:

Thanks, yes that is exactly the thing I’m thinking of !!
As it’s relatively cheap I can buy some and give it a go.

I think it comes in different thicknesses so will take a look at my local Home Mart to see what’s available .

In your use case I strongly recommend either the cheapest, it has brown paper on one side silver on the other, if you a not going to let it get wet and it should be silver side out. It is about 1,200 for 72M it may well be the best for the job

 

Or if it will get wet then the double sided silver version as I think that may be better if rained on.

 

Whatever you buy do not get anything with foam in it as that will stop or reduce any heat transfer from tank to air.

 

Edited May 4, 2019 by sometimewoodworker

[sometimewoodworker]

2 hours ago, anderstse said:

anyone know of electric showers that cool the water,

they all just heat that I have seen. but surely there is one that could cool the water as it comes out of the shower head.

With my shower the rain head is quite warm but the hand usable shower has an almost mist setting that, when I stand back, cools the water by a few degrees.

We've had the heaters switched off for the past few weeks now.

[VocalNeal]

6 hours ago, NanLaew said:

Just needs shade from direct afternoon sunlight. Sheet of 15mm plywood 244 x 122 (or 250 x 125) attached to/suspended from the air-conditioner condenser unit bracket. Maybe about 700 baht?

 

Paint it white (optional).

Nah too simple.

 

I'm thinking one of those water misting pump systems and aim a couple of nozzles at the tank and use Latent Heat of Vapourization.

[Denim]

In our bathroom we keep a large plastic bucket with a ladle and a lid.

Very cheap and most Thais have the same thing. You get a nice cool cascade of water regardless of outside temperature.

Cheap and efficient low tech solution.

[CharlieH]

Just use a blind or curtain dropped from the eave of the roof to inside the wall.

 

The blind woukd be about 1500 baht, (like shops drop)

 

The home made way is use the black type material farmers use to shade crops etc, that would be around 500 baht. Both would shade and remove direct heat.

 

[Andrew Dwyer]

Just needs shade from direct afternoon sunlight. Sheet of 15mm plywood 244 x 122 (or 250 x 125) attached to/suspended from the air-conditioner condenser unit bracket. Maybe about 700 baht?
 
Paint it white (optional).

Another option I thought about was a polycarbonate sheet folded into an upright “ L “ shape I have some canopies round the other side of the house and they seem to do a good job .
They have a right and a wrong way for heat reduction.

[Andrew Dwyer]

In your use case I strongly recommend either the cheapest, it has brown paper on one side silver on the other, if you a not going to let it get wet and it should be silver side out. It is about 1,200 for 72M it may well be the best for the job
 
Or if it will get wet then the double sided silver version as I think that may be better if rained on.
 
Whatever you buy do not get anything with foam in it as that will stop or reduce any heat transfer from tank to air.
 

Thank you sir !!

Excellent advice.
It might get a little bit of rain splashed on it but not excessively, the rain sometimes comes sideways here !!

Just had a thought, should probably get the aircon cleaned before I do this, but will let you know the outcome.

[Andrew Dwyer]

In our bathroom we keep a large plastic bucket with a ladle and a lid.

Very cheap and most Thais have the same thing. You get a nice cool cascade of water regardless of outside temperature.

Cheap and efficient low tech solution.

Yup, have one of those in the 3rd toilet, it’s only used for emergencies, used it a couple of times recently as water ran out and when we tiled under the pump outside.

Have to admit though it’s a good idea and could move it into my bathroom for this hot spell !!

[mogandave]

I like hot showers, but if you really want to cool it way down, as someone else alluded to, you could install an evaporative cooler and recirculate the water in the tank. It would work just like a chiller and (if you keep the house cool) save a little on electric for the AC.

[Andrew Dwyer]

Just use a blind or curtain dropped from the eave of the roof to inside the wall.
 
The blind woukd be about 1500 baht, (like shops drop)
 
The home made way is use the black type material farmers use to shade crops etc, that would be around 500 baht. Both would shade and remove direct heat.

Thanks Charlie, the problem is to hang something from the eaves would be a bit unsightly ( see photo ) but if I wrapped the tank or boxed it in it would go unseen .



Incidentally I made a drop down 4 x 3 m tarp to shade the lounge, the outside bushes are all but dead and my Mamberry (?) arrangement inside is a few years off providing any shade [emoji51]




I think if I started hanging any more shade material from the roof my gf would think I’d lost the plot [emoji51]

[CharlieH]

 

Dont agree on "unsightly" but each to there own. ????

[Andrew Dwyer]

I like hot showers, but if you really want to cool it way down, as someone else alluded to, you could install an evaporative cooler and recirculate the water in the tank. It would work just like a chiller and (if you keep the house cool) save a little on electric for the AC.

Thanks Dave, it’s just at this time of the year it’s at its hottest and stays focused on the tank for the longest time so just looking for a cheap fix.
Gonna give the silver backed stuff a go first.

[sometimewoodworker]

26 minutes ago, Andrew Dwyer said:

Thank you sir !!

Excellent advice.
It might get a little bit of rain splashed on it but not excessively, the rain sometimes comes sideways here !!

Just had a thought, should probably get the aircon cleaned before I do this, but will let you know the outcome.

Definitely get the AC cleaned, I'm sure the film will be OK with a little rain hitting the silver side as it is water proof, it was more a comment that if the back gets too much water on it for too long it could be a problem. If you get the AC cleaned after doing the tank and it damages the film you will only have about 65M spare on your role to change it, so I would not hold off. 

[Andrew Dwyer]

 
Dont agree on "unsightly" but each to there own. [emoji16]

Agree with you there, that looks good and suits the gap perfectly, mine would look a little odd on the end . As you can see from the photo the tank is barely visible so covering it is a cheap and hopefully efficient option.

I did buy a blackout roller blind from IKEA originally for where the tarp is now and it worked great (eye bolt still there [emoji51] ), only problem being it’s 2 x 2 m and wasn’t big enough.

[Moonlover]

1 hour ago, Denim said:

In our bathroom we keep a large plastic bucket with a ladle and a lid.

Very cheap and most Thais have the same thing. You get a nice cool cascade of water regardless of outside temperature.

Cheap and efficient low tech solution.

This is our answer to the problem as well. Madam Moon hardly ever uses the 'western shower' and I also prefer the bin method as well when the incoming water is too warm.

[Denim]

1 hour ago, Moonlover said:

This is our answer to the problem as well. Madam Moon hardly ever uses the 'western shower' and I also prefer the bin method as well when the incoming water is too warm.

 

There is one other bonus with the bin solution which is that the sediment in the water which you don't see with the shower all sinks to the bottom of the bin so you bathe with slightly cleaner water.

[eyecatcher]

THis is tge reflective foil scrim.

I have half a roll left if you are in CM and you want a few metres.

[scorecard]

9 hours ago, NanLaew said:

Just needs shade from direct afternoon sunlight. Sheet of 15mm plywood 244 x 122 (or 250 x 125) attached to/suspended from the air-conditioner condenser unit bracket. Maybe about 700 baht?

 

Paint it white (optional).

Agree;  easy, inexpensive and could look good with little effort, plus maybe line the inside of the plywood with the radiant sheeting, easy to do and total cost still inexpensive. 

[Andrew Dwyer]

THis is tge reflective foil scrim.
I have half a roll left if you are in CM and you want a few metres.

Thanks for the offer but I’m 600km south of you !!

[mogandave]

I like that “Future Board” for cheap shade...