Solar performance

Chimpster

Hi folks,

I have 48 tubes and a 240 litre stainles steel tank, the tubes have good south orientation. The tank and pipe work are very well insulated.

My morning tank tempretures over the last week has been

46/47/46/48/44 (top of the tank)

I find that when I take a shower that its warm enough for me but not as warm as my partner would like, Is my system performing alright? Should I introduce an immersion boost for 15/20 minutes around 6.30am? Should I need to?

Anyone with similar readings?

CJhaughey

Chimp

I have 6m2 flat plates and a 400l tank
The average temps have fluctuated around 58ºc a few days we had to put the immersion to bring it up over the 60deg mark (Legionella) but on the whole it seems to maintain a fairly reasonable temp.
What type of tubes are they? Length of Piperun?

Chimpster

CJhaughey wrote: »

Chimp

I have 6m2 flat plates and a 400l tank
The average temps have fluctuated around 58ºc a few days we had to put the immersion to bring it up over the 60deg mark (Legionella) but on the whole it seems to maintain a fairly reasonable temp.
What type of tubes are they? Length of Piperun?

Thanks CJ.

About a 10 m run from panels to tank. They are evacuated tubes... 2 x 24...

Here are the details.

Width - 2100mm
Height - 1940mm
Frame Material - Aluminium
Insulation - Rockwool
Connection - 22mm copper
Aperture area - 2.28 m²
Absorber area - 1.93 m²
Weight - 78 kg
Volume in Manifold - 1.5 litre
Tube Number - 24
Tube Lenght - 1800mm
Tube Material - Borosilcat-glass
Tube diameter - 58mm


I know Julys weather has been poor but I would have expected a slightly higher temp to be manintained in the tank. I will use immersion for legionella purposes but I didnt think I would need to 'boost' facility during the summer period.

CJhaughey

It's not usual but occassionally we need to put the immersion on, a couple of days last month were atrocious just like winter with dull grey low cloud and heavy rain, there was very little radiation reaching the panels so they were only 35º or so.
The first year we had them 2005 was crazy I remember seeing temps of 80º+!

MickLimk

Chimpster wrote: »

Hi folks,

I have 48 tubes and a 240 litre stainles steel tank, the tubes have good south orientation. The tank and pipe work are very well insulated.

My morning tank tempretures over the last week has been

46/47/46/48/44 (top of the tank)

I find that when I take a shower that its warm enough for me but not as warm as my partner would like, Is my system performing alright? Should I introduce an immersion boost for 15/20 minutes around 6.30am? Should I need to?

Anyone with similar readings?

A few questions for you:
What are you evening time temperatures like?
Much water being drawn off during the day?
Any idea what type of controller you have and what it's dt settings are?
What size is the pipework between your cylinder coil and your panel?

The weather has been brutal this summer so far but I'm still holding out hope for August! Apart from that, maybe you should consider letting your partner go first in the shower...;)

Chimpster

MickLimk wrote: »

A few questions for you:
What are you evening time temperatures like?
Much water being drawn off during the day?
Any idea what type of controller you have and what it's dt settings are?
What size is the pipework between your cylinder coil and your panel?

The weather has been brutal this summer so far but I'm still holding out hope for August! Apart from that, maybe you should consider letting your partner go first in the shower...;)

Evening temp in the tank is only 1/2 degrees lower than the morning temps so the tank is holding the heat quite well.

Only 2 showers being drawn off in the mornings currenty and a minimal amount of hot water in the kitchen taps.

Its a TDC 3 controller, I am looking at changing the delta T alright, they are both set at the default 10degrees as far as I know. Any recommendations on changes to this?

The pipe work is standard 10mm as far as I know, I could be wrong though? There is about a 8m run to the panel and 8m back.

Thanks.

MickLimk

Chimpster wrote: »

Evening temp in the tank is only 1/2 degrees lower than the morning temps so the tank is holding the heat quite well.

Only 2 showers being drawn off in the mornings currenty and a minimal amount of hot water in the kitchen taps.

Its a TDC 3 controller, I am looking at changing the delta T alright, they are both set at the default 10degrees as far as I know. Any recommendations on changes to this?

The pipe work is standard 10mm as far as I know, I could be wrong though? There is about a 8m run to the panel and 8m back.

Thanks.

Might be best if you post all the settings of your TDC3 here. I don't think 10°C for both would right. The delta T settings are normally different by 4°C or more depending on the system.

There are a couple more things worth having a look at:
Is there a flow meter in your system? If so, what's the flow rate set at?
Is your pipework really 10mm? 15mm (1/2") is more usually installed in Ireland.
What's your system pressure gauge showing?
Was the system completely bled of air?
Are you using variable pump speed control?
What setting is your circulation pump at?
What brand of tubes are they?
Do you have any heat dump arrangement installed?

To be honest, it is very difficult to assess system performance without seeing the actual setup. Have you observed the panel temperatures on any day when the sun is actually shining? It is possible that you setup is correct and that the weather is so bad that what you're seeing is real performance. However, I would expect more from a setup with 48x 58mm tubes feeding a 240 litre tank even in this weather.

MickLimk

Chimpster wrote: »

Hi folks,

I have 48 tubes and a 240 litre stainles steel tank, the tubes have good south orientation. The tank and pipe work are very well insulated.

My morning tank tempretures over the last week has been

46/47/46/48/44 (top of the tank)

I find that when I take a shower that its warm enough for me but not as warm as my partner would like, Is my system performing alright? Should I introduce an immersion boost for 15/20 minutes around 6.30am? Should I need to?

Anyone with similar readings?

Just remembered this: <SNIP>

This guy has a similar size panel, a smaller cylinder, slightly more usage (?) but a non-ideal orientation. Also looks like they've got more losses due to less insulation than yourself. Obviously pipework length, insulation, shadowing etc. all play a part but maybe this wouldn't be a million miles away from what you'd expect to see?

It could be that the weather so far in July really is that bad especially if you look at his June temperatures... <SNIP>


Mod edit: While your intentions are probably good we dont allow links to businesses. You may PM the link to anyone who wants it.

Chimpster

Solved the problem.

The temp from the taps was actually 10 degrees higher than the temp from the shower. The mixer in the shower needs to be balanced as I found out from my plumber.

Great day out today the tank was 60 degree this evening, and 82 degrees on the panels at 8pm this evening.

Thanks for all the help folks.

MickLimk

MickLimk wrote: »

Just remembered this: <SNIP>

This guy has a similar size panel, a smaller cylinder, slightly more usage (?) but a non-ideal orientation. Also looks like they've got more losses due to less insulation than yourself. Obviously pipework length, insulation, shadowing etc. all play a part but maybe this wouldn't be a million miles away from what you'd expect to see?

It could be that the weather so far in July really is that bad especially if you look at his June temperatures... <SNIP>


Mod edit: While your intentions are probably good we dont allow links to businesses. You may PM the link to anyone who wants it.

Sorry about that Muffler. I've no relationship with the company mentioned in that website, don't know them from Adam. Wouldn't have posted the link other than the fact that it has been left in two other threads, one posted on May 2nd, other on July 7th.

For anyone who missed it, the link was to a website that graphs and records the temperatures (panels, top, middle & bottom of cylinder) of a solar system that's installed in Cork somewhere. It could be a useful rough guide as to what to expect from a similar sized system.

AlanD

any chance you might PM me that link?

Thanks

mad m

Just got 3 flat panels installed myself, 300 litre cylinder. getting over 60+ and temp is fine for our needs....Windhager cylinder and panels btw.

Dopey

mad m wrote: »

Just got 3 flat panels installed myself, 300 litre cylinder. getting over 60+ and temp is fine for our needs....Windhager cylinder and panels btw.

How much did that set you back?

mad m

Dopey wrote: »

How much did that set you back?

Was quoted 6500k....At end the rep through in the vat on top,which I wasn't pleased about....So 7200......Waiting on my 1500 back from SEI.