East West System in Maidstone Kent

[chickensoup]

 Very nice job Tim, but can i suggest twisting the pumps up vertically. Also i cant tell very well from the pics, but do both pipes from the panel go straight down into the roofspace, if so i presume the vent is probably 10" below the highest point in the system then. How are you going to completely remove all the air with the aid of a filling pump. It is a total be-atch to remove air when the manifold is a slight tilt. never mind 10" below. If you've still got the tower and gear up i would recommend re piping to have a vent at the very top.

     sorry buddy.

                          chicken

[tim_h]

Chicken, thanks for the comments.
Not sure what you mean about twisting the pumps? do you mean turning them on the axis of the the pipe, or moving the pipework so they have the pipe connections top and bottom. It's just that I thought the way they are installed is OK according to the installation booklet (ie, make sure the shaft of the pump is horizontal).

Re the air vent, I probably did not explain very well how the pipes run, the vent is about 3 foot a meter above the manifold. I've scribbled a quick drawing to try to show it better.




What surprised me with the air vent was that after filling the system and running the pump, nearly all of the air came out of the air vent above the pumps, and hardly any came from the one above the panel. I suppose it must have just pumped through as the system is working well.

Tim

[chickensoup]

Hi Tim,
         Yes Tim turn the pumps on their axis, they need to have the bleed vent at the very top as per manufacturers instructions. As for the vent at panel i would keep a close eye on it, as the fresh water introduced into the system may settle and accumulate in the manifold as there is probably 10" of un-ventable(if there's such a word) height from centre of manifold pipe to the compression tee inside.I know the vent is a metre higher but the pipework drops down and that's where the trouble begins. It may be working but 50% less as it should be, just imagine if there was air trapped half way along the upper portion of the manifold.

        chicken
 

[tim_h]

Thanks Chicken, I'll twist the pumps up a bit!

Regarding the air vent, I can be pretty sure there's no air in the system now (I give the air bleeds a tweak every few weeks and get out less air than a gnats fart!) It's now been running since October but took me this long to get round to posting up the pictures! In fact if the collectors were working any better I'll soon be having to start looking into dumping the heat or covering them up.... The store heated from 48C to 76C last sunday, that's about 7.5kWh on a April day, not sure how hot things will get in the summer!!

[woody]

Hi Tim I well done on the instalation but I noticed another comment about the pumps they need to be turned as described but if not possible at the very least turn them 90 deg so the water will not run into the control box if you vent them, look at the instructions that came with them they usually have a picture of acceptable instalation regards A.

[Terrier]

The pumps need to stay as they are, if you turn them up, the bearings in top of the motor will dry out, and in time will destroy the bearings, if you look at the installation instructions they will show which orientation is allowed, I have changed countless pumps that have been installed in the upright position.

Terrier.

[lightfoot]

Terrier is correct, pumps should always be installed with the impeller shaft horizontal/level - not vertical with the vent screw on top!  And ideally the pump head should be rotated to avoid the chance of water ingress into the electrical controls/connection - but going by your photos, you may not have enough room to play with?

Also, ideally the solar panel should be piped up so that the manifold is highest point in the system, so if/when the solar system stagnates, the water/glycol can be displaced/drain from the panel/manifold and minimise the production of steam in the system.

Tony.

[tim_h]

Thanks all for the clafication on pump orentation. I'm assuming turning the terminal box position on the pump involves opening a watertight seal, in which case I'll leave them as is to reduce the chances of introducing a leak. Tony, you're right, space is very limted in the cupboard, otherwise they would have been installed in the normal way.

Tony, thanks for the heads up on the manifold pipework, I must have missed that bit in the solar install instructions, but to move the pipework would be a complete pain in the ar$e. What's the worst case scenario if I left the system as it is?

[Richard Owen]

My pipes rise from the panel in a similar way to yours.

I forced the system into stagnation last summer just to see what would happen.

The answer: nothing much.

The temperature slowly rises with the pressure until the pressure relief valve lets go and then it just sits there. When you turn the pumps back on it all returns to normal.

Drama free really.

There's a lot talked about the problems of air locks in the system under stagnation. Which, to my mind, is all rubbish. There's no extra air in the system under stagnation. There's steam, but not air. And, if some water does enter the manifold and is flashed to steam, the steam that's pushed out of the other end of the manifold condenses, so it's all fine.

[Pat_]

Richard,
What you say makes sense but the fact is that my system recently stagnated (I was unfortunately in Budapest at the time) and afterwards the pressure of the again working system had risen from 1 Bar to 1.1Bar, and there was the sound of bubbles going though the pump. For the previous 6 months the system didn't make a sound. I conjectured that a gas had been produced by the overheating, and someone suggested on here that it may have been hydrogen. I bled it off (without trying to light it) and the pressure returned to 1 Bar.

It's hard to see how this could have been caused by air.