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eggs
24-10-2012, 08:09 PM
Evening all.

Does anyone have any experience with this (http://solarelectricitysystems.co.uk/thermodynamic.html) type of system?

One of my customers tells me they are the best thing since sliced bread..Gonna be bigger than double glazing.:eek:

Cheers Eggs

SeanB
24-10-2012, 08:49 PM
Fridge evaporator plate painted black and flung on the roof. No problem, as long as you pull the heat out to keep it cool, and keep the snow and frost off in winter.

Solar heaters here can get up to boiling, when you see a little plume of steam wafting out the top of 1000 Jondolo roofs making a cloud. That is why there is a mixing valve installed ( regulations) to keep the output water under 55C.

Peter_1
24-10-2012, 09:36 PM
I like step 4 The cooling gas then passes through a valve reverting back into a liquid where it runs back into the panel where the process begins again. Interesting valve :-)

eggs
24-10-2012, 09:52 PM
I like step 4 The cooling gas then passes through a valve reverting back into a liquid where it runs back into the panel where the process begins again. Interesting valve :-)

That is the thing Peter.

These things are being marketed by the manufactures to the plumbers and heating engineers who have no idea how these things work.
My client (a combustion heating company) has a contract to install 30 of these a week and he has no idea how they work.

I am the only company he knows who has the F Gas and part p for domestic and f gas and 17th ed for commercial work.

Fill your boots chaps, these systems are coming.

eggs

Goober
24-10-2012, 10:03 PM
In theory a great idea, lots in use here, but not a proven technology. To fine a balanced system. Any slight deviation from the slim design envelope causes mayhem. Similar to airsource water heaters...

eggs
24-10-2012, 10:15 PM
Good evening.

Can you please explain what problems can be expected? I'm not being pedantic, but I want to be furnished with all the info possible before i get involved.

Cheers

Eggs

Tesla
24-10-2012, 10:49 PM
Hi eggs
I worked on some problems with these panels nearly 10 years ago in NZ and the probs were compressor burn out due to short cycling which was fixed with an additional relay and timer for anti recycle. Limited performance at near 0degC ambient. With good control it could take advantage of the making more hot water during the warmest part of the day.

frank
25-10-2012, 08:44 PM
Seems like it a normal ASHP with the evaporator in a slim, wall hung panel instead of a finned coil as we know them?
The blub says the gas goes into a compressor, so it's not free heat after all.

chemi-cool
25-10-2012, 09:33 PM
These are very big here and the bottom line is straight forward, you invest and start saving, I have a good friend in Denmark who sells and erect these panels to the privet sector, small systems up to 10KW.

The only problem is the British weather, how much electricity you can make in two sunny weeks per year.
And as for you Mr eggs, if i were you, I would jump on that wagon as soon as I can, trends make good income for those who act!!

MikeHolm
26-10-2012, 11:43 AM
These are very big here and the bottom line is straight forward, you invest and start saving, I have a good friend in Denmark who sells and erect these panels to the privet sector, small systems up to 10KW.

The only problem is the British weather, how much electricity you can make in two sunny weeks per year.
And as for you Mr eggs, if i were you, I would jump on that wagon as soon as I can, trends make good income for those who act!!

It's not PV Chemi, it is an evap on the wall that would replace a normal solar hot water panel. I'm looking into them as well as no one is selling them here but given how most installers can f**k up a simple SDHW system, I can see how they can REALLY F**K this up.

On a related note, we just finished monitoring 100 SDHW, 2 panel water heaters (different types and installers) and 70% of them fall well below expected heat production and all the reasons are all about fine installation details.

chemi-cool
26-10-2012, 05:23 PM
It's not PV Chemi, it is an evap on the wall that would replace a normal solar hot water panel. I'm looking into them as well as no one is selling them here but given how most installers can f**k up a simple SDHW system, I can see how they can REALLY F**K this up.

On a related note, we just finished monitoring 100 SDHW, 2 panel water heaters (different types and installers) and 70% of them fall well below expected heat production and all the reasons are all about fine installation details.
I could not open the link so I thought it was about solar panels.

Peter_1
26-10-2012, 05:37 PM
The only problem is the British weather, how much electricity you can make in two sunny weeks per year.
And as for you Mr eggs, if i were you, I would jump on that wagon as soon as I can, trends make good income for those who act!!
This trend already finished in Belgium Chemi since beginning this year, since they stopped funding these systems.

chemi-cool
26-10-2012, 08:45 PM
Now that I have seen the link, its a simple air to water heat pump, the only differences is that the evaporator is on the roof. i doubt if would work in hot climate.

MikeHolm
27-10-2012, 11:50 AM
This trend already finished in Belgium Chemi since beginning this year, since they stopped funding these systems.

Which systems Peter? PV or the Refrig/solar waters

Bigfreeze
27-10-2012, 11:13 PM
Load of crap imo. Alright if the temp is decent but if its single digits moisture will condense on the panel and freeze, evap temp will drop and more moisture will freeze. Same principle as the ice stick which always ends up as a big block of ice with no means of defrost and terrible COP's.
Over here they're flogging them as solar panels as you can get grants for solar but not heat pumps. They're even trying to flog them as heating systems by linking panels in series. Also what happens when its very warm and you need to produce hot water. The evap temp would be crazy and you're likely to cook your compressor because theres no cooling effect from the refrigerant.

mad fridgie
27-10-2012, 11:38 PM
This are well over 20 years old, in NZ and Aus under the quantum name.
I have been asked by many engineers to help sort these out.
No anticycle, wrong TEVs, incorrect charge.
All changed to a more standard ASHP

MikeHolm
27-10-2012, 11:45 PM
I decided they were bollocks before so I forgot about them...... so I think I will decide to forget about them again. What were we talking about.....?

eggs
29-10-2012, 10:15 PM
Evening.

We installed one of these this weekend. Here are my thoughts so far:

When switched on the water temp was raised from 8 to 12 deg c within 30 mins.
Evaporating temp was -12 deg C at 6 deg C ambient on 134a (no discharge or liquid ports)

What could be the maximum discharge temps under these conditions? I didn't get SH or SC measurements as quite frankly there wasn't enough money in the job to hang around once it was switched on.

Cheers

Eggs

Quality
30-10-2012, 07:30 PM
I have worked on a few (fridge side). the cylinder and wet plumbing equipment (on the ones I have seen) do not have wras approval hence its not legal to be installed in this country

eggs
30-10-2012, 08:11 PM
On the cylinder we installed we had to add the temp prv etc.. to comply. I'm going back on Thursday to see how well/bad it is working :eek:

When I had a look inside the thing there was no hot gas defrost circuit, so with 134a evaporating at -12 ish on a garage roof in January at -5..........I see a big block of ice forming. I wonder how well it will work then?

Eggs

Coorsman777
30-10-2012, 09:05 PM
Check out the website and I do not follow. I am assuming it takes electricity to run compressor? So how can it be "100% Free" if it uses elec? Or are we in the US to far out of the loop on this technology?

Bigfreeze
30-10-2012, 09:55 PM
Evening.

We installed one of these this weekend. Here are my thoughts so far:

When switched on the water temp was raised from 8 to 12 deg c within 30 mins.
Evaporating temp was -12 deg C at 6 deg C ambient on 134a (no discharge or liquid ports)

What could be the maximum discharge temps under these conditions? I didn't get SH or SC measurements as quite frankly there wasn't enough money in the job to hang around once it was switched on.

Cheers

Eggs

An evap temp of -12 when you're trying to achieve a condensing temp of 50C+ should tell you how efficient this junk really is.

eggs
01-11-2012, 08:56 PM
Just got back from site and it all looks good.

I measured the water temp at 55 deg c from the taps, and the customer says it takes two hours to raise 300l of water from 6 deg to 55.
Ambient air has averaged 7 deg since we installed it.

There was just a few minor leaks from my plumbing......:(....but all fixed now.

Got another to install next Thursday....:)

Eggs

MikeHolm
01-11-2012, 09:14 PM
Can you post any install pics and/or install docs?

eggs
01-11-2012, 09:27 PM
The brand that we are installing can be found here (http://www.ultimasolar.co.uk/).

The pics are in the office, I post them in the morning.

The customer is so pleased they want the one to run their central heating installed as soon as they are tweaked for the UK market.

Eggs

mad fridgie
01-11-2012, 11:45 PM
Have a look at the brochure, working ambient range 5 to 45C, but does include an element.

Must be a great system 8.5Kw plus losses, so if we remove the 2Kw for the element, heat pump is producing 6.5Kw, 500watt input, WOW COP is 13, and at 7C ambient.

Must have some wonderbar compressor, Best COP I get an any condition is 10.

mikeref
02-11-2012, 04:09 AM
In the specs it says 3 to 7 for COP. Got you thinking eh Mad f.
Wonder if the refrigerator style evap plate is hail proof..
The neighbours had a similar set up some years ago before they changed to a Quantum air source. Compressor died from over heating, and it ran on R22.

eggs
09-11-2012, 06:52 PM
Installed another one of these yesterday..why is the suction line wound around the compressor :confused:

http://img72.imageshack.us/img72/786/dsc0035lv.jpg (http://imageshack.us/photo/my-images/72/dsc0035lv.jpg/)

Uploaded with ImageShack.us (http://imageshack.us)

Cheers

Eggs

eggs
09-11-2012, 07:08 PM
http://imageshack.us/a/img59/1742/pictures2cdnovember187.th.jpg (http://imageshack.us/photo/my-images/59/pictures2cdnovember187.jpg/)
http://imageshack.us/a/img231/9458/pictures2cdnovember193.th.jpg (http://imageshack.us/photo/my-images/231/pictures2cdnovember193.jpg/)
http://imageshack.us/a/img855/4078/pictures2cdnovember184.th.jpg (http://imageshack.us/photo/my-images/855/pictures2cdnovember184.jpg/)

Quality
09-11-2012, 09:24 PM
I have not looked at the performance of these systems but the compressor coil could be an half hearted liquid line sub cooler in reverse which could make sense.
PS I still think the application is great and new but the technology is not new

eggs
09-11-2012, 09:46 PM
Even when the compressor has been running for a couple of hours it is still cold to the touch.:confused:.....not chilly or lukewarm....cold??

Eggs

hookster
09-11-2012, 10:20 PM
Here is a thought! If I increased the surface area of the source and then added a source of fluid motion to increase the transfer coefficient. hmmm now why are they not selling air source heat pumps!

mad fridgie
09-11-2012, 10:22 PM
They are running at little or no superheat, to keep the compressor cold, to attempt to ensure no liquid is returning, they wind the suction around the compressor, using some of the heat of rejection to boil and add superheat, not even useful!
As far as running a couple of hours, the tank will not be heated yet, I do not count the top couple of %
There is no magic in refrigeration, just in marketing

Find the compressor model and refrigerant, even better working pressures and I can soon tell you what it is doing.

eggs
09-11-2012, 10:27 PM
Here is a thought! If I increased the surface area of the source and then added a source of fluid motion to increase the transfer coefficient. hmmm now why are they not selling air source heat pumps!

Hey, I'm a ducter with a few clever tools, a copy of Althouse's book and some good employees :D can we have this in English please?

Eggs

eggs
09-11-2012, 10:33 PM
Find the compressor model and refrigerant, even better working pressures and I can soon tell you what it is doing.

All I know is that it 134a evaporating at -12 deg C. As mentioned in a previous post it is raising 200l of water from 6 deg c to 55 in about 2 hours.
Let me know a full list of parameters you require and i will go back to site and get them.......it all has me baffled.

eggs

mad fridgie
09-11-2012, 11:11 PM
All I know is that it 134a evaporating at -12 deg C. As mentioned in a previous post it is raising 200l of water from 6 deg c to 55 in about 2 hours.
Let me know a full list of parameters you require and i will go back to site and get them.......it all has me baffled.

eggs

Was 300L or was 200L.

Answer to your question to hookster.

You have a wet towel, you need to dry it. "heat/energy transfer is required"

1 do you leave it a pile are crumbled up in a corner
2 you hang it flat on windy cloths line.

Which drys first?

No 2, why it has increased surface area (the bit that is in direct contact with the air) and an added source of fluid motion "the wind"

So an air source system, has lots of surface area (look at all the fins) and has fluid motion "the fan"

eggs
10-11-2012, 12:15 AM
Was 300L or was 200L.

Sorry my typo, the ones we have fitted are 200l.



You have a wet towel, you need to dry it. "heat/energy transfer is required"

1 do you leave it a pile are crumbled up in a corner
2 you hang it flat on windy cloths line.

Which drys first?

No 2, why it has increased surface area (the bit that is in direct contact with the air) and an added source of fluid motion "the wind"

So an air source system, has lots of surface area (look at all the fins) and has fluid motion "the fan"

:confused: So the heat from the compressor is being used as an insurance policy? Is this not good?

My question now is "why then do we need the solar/evap panel, could you just not have more coils around the compressor?"

mikeref
10-11-2012, 12:31 AM
They could have used an accumulator but guessing copper tube has more surface area when wound around compressor. As for more coils rather than external evaporator, there wouldn't be enough surface area, then condensation problems.

hookster
10-11-2012, 12:26 PM
:p At least you have a decent book! It is probably thick enough to stand on and reach that duct work!

Thank mad for the explanation I was just wondering when the first air source and solar combination heat pump would be released for us "Sunnier Climates"

Ps I cam hear the factories in China ramping up to produce TiNox coated exchangers as we speak

MikeHolm
11-11-2012, 01:43 PM
They could have used an accumulator but guessing copper tube has more surface area when wound around compressor. As for more coils rather than external evaporator, there wouldn't be enough surface area, then condensation problems.

Na, they wouldn't have used more coils. The problem with solar is that you quickly run out of desire to buy the system when you add to the cost. An accumulator would add to much to the cost and it is really price sensitive.

MikeHolm
11-11-2012, 01:44 PM
http://imageshack.us/a/img59/1742/pictures2cdnovember187.th.jpg (http://imageshack.us/photo/my-images/59/pictures2cdnovember187.jpg/)
http://imageshack.us/a/img231/9458/pictures2cdnovember193.th.jpg (http://imageshack.us/photo/my-images/231/pictures2cdnovember193.jpg/)
http://imageshack.us/a/img855/4078/pictures2cdnovember184.th.jpg (http://imageshack.us/photo/my-images/855/pictures2cdnovember184.jpg/)

Tank is upside down, but I like the hanger.

Airconjon
30-11-2012, 08:03 PM
Why do they lag liquid and suction lines outside the building ? Surely it's better not too with the idea of gaining as much heat as possible increasing discharge temperature and water temperature ? Only reason I ask is they struggle in low ambient temperatures just like today 18 evap panels -3 ambient very low suction pressure as you would expect but full site glass plus compressors frosting ie slugging liquid .... Brand new install ... All I can thing of is tev ??