Refill hot water solar panel

[Rad1o]

We have a hot water solar panel on the roof. A couple of days ago the pump was making a sqeeching noise and I thought the pump was broken. I disconnected the pump and planned to look for a new one but also wanted to check the function and removed it. On the bench the pump worked fine and I refitted it, but despite the panel showing a higher temperature than the hot water cylinder the water was not getting any warmer. Even though there was a dribble of liquid coming out of the pipe I think the system has run dry and needs refilling / recharging.
How best can I refill the system???

When it was fitted the company put a T with an isolation valve under the garage roof. The T has a 15mm connection.
The solar panel is on the same level as the hot water cylinder.

Has anyone refilled their solar panel using a pump?
Are there any DIY / pumps available for this kind of job?

 

[muggles]

It needs filling with the correct solar fluid, using a special filling pump which will remove all the air from the fluid as it fills. These pumps are normally available from hire centres, but all the hire centres are shut until further notice so you may have to wait. It'll also need doing very early in the morning before the panel starts warming up - pump cold fluid into a hot panel and the results are as spectacular as they are expensive.

 

[Rad1o]

The solar fluid is available as pre mix.

Is this the kind of pump you mentioned?
https://www.manomano.co.uk/p/ridgid-1450-50072-pressure-test-pump-725-psi-50-bar-1395399

 

[denso13]

Is this the kind of pump you mentioned?

No, that is for pressure testing. Something like this https://www.machinemart.co.uk/p/rothenberger-135-solar-heating-pump-centrifuga/ or https://www.tedbartinkerhire.co.uk/tool-hire.php?tool-hire=rems-solar-push

 

[Rad1o]

Thanks for the replies.

What is the normal or typical amount of solar fluid for a system. Our panel is about 3 x 1 m and the distance to the cylinder is 15m?

 

[MeldrewsMate]

I see no evidence of a pressure gauge. How will you know when to stop the filling process?
Where did your old fluid go? Is there evidence of a chronic leak?
What system pressure should you have?
Having that data to hand will help you avoid many pitfalls.
You can buy premixed solar fluid from BES, and have it delivered. www.BES.co.uk. It has expensive chemicals in it which prevent corrosion and that are stable at the high temperatures that solar systems can get to.

 

[Rad1o]

The pressure gauge, expansion vessel and blow off valve are in a different location. It reads Zero. I do not know where the fluid has gone, but we have always had some escape from the valve.

The panel temperature readings are up to 80°C. we have some shade from neighbour's trees now from the west.

 

[ajstoneservices]

What is that filling loop for ?
You can convert a garden sprayer to refill the system if there is a manual air vent fitted. Don't attempt to refill it when the panel is in full sun.

edit: search navitron to find out how to use the sprayer.

 

[Rad1o]

Thanks for the advice on Navitron. I got some helpful pictures but would like to know what the parts use are.
I did not get far asking for the parts involved though.

Can anyone tell me what connectors they would have used on attached picture?