reaching pool temperature with a heat exchanger

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pendle
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reaching pool temperature with a heat exchanger

Post by pendle »

Someone will know this!
Our season starts mid May so we are thinking of starting the heat exchanger up in mid April.
Should we leave it on 24/24 or only during the day.Someone has told us that if you leave it on during the night it brings the temperature back down.Is this right?
Pendle
la vache!
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Re: reaching pool temperature with a heat exchanger

Post by la vache! »

pendle wrote:Someone will know this!
Our season starts mid May so we are thinking of starting the heat exchanger up in mid April.
Should we leave it on 24/24 or only during the day.Someone has told us that if you leave it on during the night it brings the temperature back down.Is this right?
Pendle
No! I start mine up at the end of March and leave it on 24/24. It takes about a week to get up to 24°C. It would take a lot longer if I didn't leave it on at night as the temperature would fall again at night. The technician who came to service the heat pump also confirmed this.
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Alan Knighting
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Post by Alan Knighting »

pendle wrote:Someone has told us that if you leave it on during the night it brings the temperature back down. Is this right?
It most certainly is. Many heaters incorporate a thermostatic switch to avoid this problem. If your’s does not then switch it off overnight.

Alan
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Richard D
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Post by Richard D »

Heat exchangers rely on a temperature gradient between the source and the destination. If you are using an air-water heat exchanger, then the lowest operable air temp will depend on the efficiency of the exchanger. A good quality one will shut itself down automatically if the air temp drops below a pre-determined level. eg. A good quality Hayward heat exchanger automatically shuts down at around 10 degrees C.

Normally you can pick up this information from the manufacturer. The best systems use constant temperature "reservoirs" like wells, lakes or an underground network of pipes; these sort of systems can often extract heat 24/7 summer and winter.
la vache!
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Post by la vache! »

Alan Knighting wrote:
pendle wrote:Someone has told us that if you leave it on during the night it brings the temperature back down. Is this right?
It most certainly is. Many heaters incorporate a thermostatic switch to avoid this problem. If your’s does not then switch it off overnight.

Alan
Forgot to say mine switches off automatically if the temp goes below 3°c. The temperature has never fallen during the night.
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enid
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Post by enid »

Finally got my old man to agree in principle to heating the pool. A heat exchanger seems the best and easiest route. Our pool is 10 x 4.5 with a depth from 1m - 2m. Have any of you recommendations? Are they easy to install? What sort of money am I to trying to squeeze out of him? Are they easy to run?

Any feedback gratefully received (I would just LOVE to be swimming at 24° in April :) )
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Alan Knighting
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Post by Alan Knighting »

Enid,

Based on your figures you want to heat something a little less than 70 cubic metres of water. For that, a heat exchanger would cost you no more than 3000€ at your local “brico”.

Are they easy to install? Yes, almost ridiculously so.

Are they obtrusive? Not in the slightest. They are the size of a large suite-case and they can be positioned wherever you like.

Are they easy to run? Totally, they are fully automatic.

Are they cheap to run? They rely on a few sensors and a couple of electric motors and electric motors are just about the most efficient use of electricity known to man.

Alan
la vache!
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Post by la vache! »

Alan Knighting wrote:Enid,

Based on your figures you want to heat something a little less than 70 cubic metres of water. For that, a heat exchanger would cost you no more than 3000€ at your local “brico”.

Are they easy to install? Yes, almost ridiculously so.

Are they obtrusive? Not in the slightest. They are the size of a large suite-case and they can be positioned wherever you like.

Are they easy to run? Totally, they are fully automatic.

Are they cheap to run? They rely on a few sensors and a couple of electric motors and electric motors are just about the most efficient use of electricity known to man.

Alan
I switch mine on at the end of Mars and off at the beginning of October. I set the temperature accordingly and it runs whenever the pool temp drops below that. I've had it 7 years and have never had a problem with it. It is not expensive to run and as Alan said, is very unintrusive.
la vache!
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Post by la vache! »

One more thing - for my heat pump, I had to have a tri phase electricity supply. Not sure if it is the case for all of them, but mine certainly did.
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enid
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Post by enid »

Thanks for the feed back - we have tri phase here LV so that shouldn't be too difficult. I'll start looking around! :D
la vache!
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Post by la vache! »

Mine is a PSA Optipac Titane heat pump if you are interested, Enid. It was about 5000€, back in 2000.
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enid
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Post by enid »

Merci - I'll have a look at the price now!!!! Did you fit it yourself - if yes was it easy?
la vache!
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Post by la vache! »

enid wrote:Merci - I'll have a look at the price now!!!! Did you fit it yourself - if yes was it easy?
I didn't install it myself Enid, it was installed by the pool company.
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enid
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Post by enid »

I knew you'd say that!!! Just picking u on the comment re finding one cheaper in a Brico. Kevin has enough work to do. :D I'm going to ring our pool company today.
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J&J
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Post by J&J »

Our experience is pretty much the same as LV - except we didn't have the extra benefit of an abri which she has. We generally switched the heating on around mid-April. Over the last few years I would say it has taken, at best six days and, at worst 3 weeks to get the water temperature up to 26/27 degrees. I find that the pool is just about usable (if you are keen or a child) from about 24 degrees but needs to really reach 26 to be comfortable.

Again, like LV, we left it on 24/7 and it worked very efficiently. It too had a cut out if the outside air temperature dropped below 5 deg. If it's really cold at night then the water can easily drop a degree, or maybe two, anyway even with a cover on despite the heater. Luckily that doesn't happen too often although last year it did happen in the May half term week - not that anyone was interested in swimming as the weather was so poor !

I can't remember the name of ours but it ran very quietly and efficiently and was installed by the local Everblue deaer in Rennes (Ouest Piscine).

Titch.

~ all gone, signed yesterday, money in the bank ~
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