solar water heater luke warm
#1
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solar water heater luke warm
Got a solar water heater on the roof but it only seems to give around 1 shower's worth of hot water.
Is that normal this time of year?
It's a 220 L capacity. I assume it's fillingup with cold water after a bit is used in the kitchen/shower as there is no intermediate tank to store the hot water so it all comes from the tank on the roof.
It's a new build so don't have much experience with these.
Is that normal this time of year?
It's a 220 L capacity. I assume it's fillingup with cold water after a bit is used in the kitchen/shower as there is no intermediate tank to store the hot water so it all comes from the tank on the roof.
It's a new build so don't have much experience with these.
#2
Joined: Jun 2011
Location: In the middle of 10million Olive Trees
Posts: 12,053
Re: solar water heater luke warm
Modules nearly always produce less than their rated peak power in real-life conditions.
The output is based on a peak sun temp of 25c - over the past few weeks here we have been dull and overcast, temp of 8-10c at best.
you have done the right thing but just don't expect that because the sun came up at 0810 this morning that is the way to a hot shower.
also the only way to ensure maximum collection is to have the pv cell follow the sun - exceedingly rare in the average household as only military and top end commercial facilities can do that.
http://www.windandsun.co.uk/informat...lating-pv.aspx
you will need a backup during the winter even in Spain
`
The output is based on a peak sun temp of 25c - over the past few weeks here we have been dull and overcast, temp of 8-10c at best.
you have done the right thing but just don't expect that because the sun came up at 0810 this morning that is the way to a hot shower.
also the only way to ensure maximum collection is to have the pv cell follow the sun - exceedingly rare in the average household as only military and top end commercial facilities can do that.
http://www.windandsun.co.uk/informat...lating-pv.aspx
you will need a backup during the winter even in Spain
`
#3
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Joined: Jan 2010
Posts: 439
Re: solar water heater luke warm
Modules nearly always produce less than their rated peak power in real-life conditions.
The output is based on a peak sun temp of 25c - over the past few weeks here we have been dull and overcast, temp of 8-10c at best.
you have done the right thing but just don't expect that because the sun came up at 0810 this morning that is the way to a hot shower.
also the only way to ensure maximum collection is to have the pv cell follow the sun - exceedingly rare in the average household as only military and top end commercial facilities can do that.
http://www.windandsun.co.uk/informat...lating-pv.aspx
you will need a backup during the winter even in Spain
`
The output is based on a peak sun temp of 25c - over the past few weeks here we have been dull and overcast, temp of 8-10c at best.
you have done the right thing but just don't expect that because the sun came up at 0810 this morning that is the way to a hot shower.
also the only way to ensure maximum collection is to have the pv cell follow the sun - exceedingly rare in the average household as only military and top end commercial facilities can do that.
http://www.windandsun.co.uk/informat...lating-pv.aspx
you will need a backup during the winter even in Spain
`
I'm wondering if a 300L would have been better.
As it's a direct system, my figuring is that a shower might use 70-100L. On a direct system, it is immediatel topped up with cold water. That lowers the overall temp of the tank. Isn't this effect less with a bigger tank?
#4
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Re: solar water heater luke warm
It was hot the other day, just only for one shower or so.
I'm wondering if a 300L would have been better.
As it's a direct system, my figuring is that a shower might use 70-100L. On a direct system, it is immediatel topped up with cold water. That lowers the overall temp of the tank. Isn't this effect less with a bigger tank?
I'm wondering if a 300L would have been better.
As it's a direct system, my figuring is that a shower might use 70-100L. On a direct system, it is immediatel topped up with cold water. That lowers the overall temp of the tank. Isn't this effect less with a bigger tank?
Is the tank on the roof supposed to connect direct to the electric tank and then electric tank plumbs into the house water?
#5
Joined: Jun 2011
Location: In the middle of 10million Olive Trees
Posts: 12,053
Re: solar water heater luke warm
you say it is a new build - what does the original installer say ??
seems to me to be a bit of a problem to have all that kit and only get enough water for one shower then have to wait 24hrs for another one.
so although the weather may not be perfect this time of year, are the pv cells in the right direction ? At least you aren't paying for anything except the install
as this is Spain try thinking outside the box - why not have an instantaneous water heater, then you will only be heating the water that is used ?
`
seems to me to be a bit of a problem to have all that kit and only get enough water for one shower then have to wait 24hrs for another one.
so although the weather may not be perfect this time of year, are the pv cells in the right direction ? At least you aren't paying for anything except the install
as this is Spain try thinking outside the box - why not have an instantaneous water heater, then you will only be heating the water that is used ?
`
#6
Re: solar water heater luke warm
There are various ways of providing sufficient hot water from a solar system.
One is with an inbuilt immersion heater in the solar tank for use when there is insufficient sun.
The other is to run the hot water through a gas water heater, if the water from the solar is hot enough the gas heater will not fire up, however if the solar water is cold the gas heater comes into play.
One is with an inbuilt immersion heater in the solar tank for use when there is insufficient sun.
The other is to run the hot water through a gas water heater, if the water from the solar is hot enough the gas heater will not fire up, however if the solar water is cold the gas heater comes into play.
#7
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Re: solar water heater luke warm
you say it is a new build - what does the original installer say ??
Original installer said it would need a 2nd heater in winter but was not installed because it was thought at the time that the solar would be enough.
They plumbed in the pipes for the supplementary heater though, which is lucky.
I assume it's a simple job of just connecting the pipes...
I've seen 50litre electric heaters in Aki for around 80 euros.
How much are plumbers normally in Spain?
Last edited by Scribble; Dec 25th 2012 at 12:02 pm.
#8
Re: solar water heater luke warm
Yes you will need back up in the winter , If you buy the small electric boiler you can feed it with pre heated water via your swh, you can also fit a by pass for when the solar hot water can be used direct
Is it a flat plate or vacuum tube swh ?
Tony
Is it a flat plate or vacuum tube swh ?
Tony
#9
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Re: solar water heater luke warm
I'm just wondering as there are 2 blocked pipe exits in the kitchen cupoard. I'm wondering how these are bypassed at the moment as I can't find a valve anywhere to bypass at the moment.
#10
Re: solar water heater luke warm
If you only have solar hot water at the moment, you must determine where it feeds into the house hot water piping, dis connect this and feed it into your new electric boiler cold side . it is also advisable to fit a by pass.
In the kitchen where the blocked holes are is there a flexi pipe looping from one hole to another ?
Cheers Tony
In the kitchen where the blocked holes are is there a flexi pipe looping from one hole to another ?
Cheers Tony
#12
Re: solar water heater luke warm
Ok, then you really need to go back to the swh and follow the pipe to see where
it enters the hot water system.
If the connection is inside you may be able to fit a stop cock,
Fit the hot water cylinder to the blanked off connections in the kitchen ( with another stop cock on the hot out side )
So you can run the systems in parallel by turning one or the other off and on.
It would be better to do it in series but might involve long pipe runs
Cheers Tony
it enters the hot water system.
If the connection is inside you may be able to fit a stop cock,
Fit the hot water cylinder to the blanked off connections in the kitchen ( with another stop cock on the hot out side )
So you can run the systems in parallel by turning one or the other off and on.
It would be better to do it in series but might involve long pipe runs
Cheers Tony
#13
Re: solar water heater luke warm
Just a thought, have you checked if the swh tank has a built in back up heater ?
Cheers Tony
Cheers Tony
#14
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Re: solar water heater luke warm
I had a look up at the heater.
For one, the builders seem to have forgotten to put the cover on.
Secondly, there is something in there that you could make an electrical connectin to but I cannot tell if it is a plug or the actual immersion heater that just hasn't been connected:
http://imageshack.us/a/img856/5250/p1030261n.jpg
http://imageshack.us/a/img585/2641/p1030260f.jpg
#15
Re: solar water heater luke warm
It could well be the heater, I am not familiar with that model,
Has the builder fitted the same unit to other property's near by that you can look at.
On the sticker dose it mention any thing about electricity eg 220v/ 1.5 kw
Tony
Has the builder fitted the same unit to other property's near by that you can look at.
On the sticker dose it mention any thing about electricity eg 220v/ 1.5 kw
Tony