Can I use a central heating powerflush machine to refill a hot water solar system

[martin ryder]

I need to refill my solar system with glycol. I really don't want to splash out £400 on a filling pump. One way round this is using a powerflush machine. I know you can hire them.

Can this be done ?

 

[Toddyplumb]

I have used our powerflush machine for glycol. You must make sure it is scrupulously clean ! We have only used it to circulate the glycol to get the air out as the powerflush machine will not pressurise it (ours wont anyway) WE then pressurise with the hand pump.
Why dont you just hire the proper gear if you can ?

 

[eaton]

i usea tub with glycol in that i put a sumbersible pump in works a treat then pump up pressure using a garden hoselock ive adapted, just leave the pump in the tub for an hour whilst your doing other bits

 

[SimonJohns]

You can adapt a garden weed killer sprayer to do it too


Sent from my iPhone using Tapatalk

 

[eaton]

wont get the air out doing that though

 

[ecowarm]

You really need the proper kit to do it properly

 

[boblydon]

The pr oper kit is the way to go if your doing quite a few, if your just doing the odd one though I use my power flushing machine to get rid of the air, the pressurise it with a rigid pressure pump.Bob

 

[lingwood]

Hi all, first post following a google of "using power flush to fill solar" and I ended up on this forum...hello.

I had a flat panel solar system installed about 4 years ago, but following some recent building works, needed to drain the system down.

All glycol saved and ready to refill, but with the mad rush for PV install by end of 12th Dec 2011, I am getting no where with a solar compnay to refill the system.

My neighbour is a gas/plumbing engineer and has the power flushing kit. But as I read this is Ok for filling the system / getting air out, but can not pressure sire the system to the approx 2.5 bar. For this I use the pressure pump /tank system?

Does this sound OK for a one off fill?

Thanks

 

[eaton]

No pressure of 2.5 will be too high, all depends on vessell size and location in regards pipe run and panels, general system will be 1.5 bar max. I'd check the glycol at 4 years as it might be no good depending on how well the system has been installed set up, if it's like any of the others I've seen recently (2 of which I've refused to do anything with) I'd be careful.

 

[ecowarm]

Hi all, first post following a google of "using power flush to fill solar" and I ended up on this forum...hello.

I had a flat panel solar system installed about 4 years ago, but following some recent building works, needed to drain the system down.

All glycol saved and ready to refill, but with the mad rush for PV install by end of 12th Dec 2011, I am getting no where with a solar compnay to refill the system.

My neighbour is a gas/plumbing engineer and has the power flushing kit. But as I read this is Ok for filling the system / getting air out, but can not pressure sire the system to the approx 2.5 bar. For this I use the pressure pump /tank system?

Does this sound OK for a one off fill?

Thanks

Welcome to the forum, and as Eaton has said the glycol at 4 years old will probably need changing.
Where are you? someone on here can proberbly come and refill and set up the system for you.

 

[lingwood]

Where are you? someone on here can proberbly come and refill and set up the system for you.

Hi,
I am In East Yorkshire, near Market Weighton.

Why would the glycol need changing, when it was working fine on removal? Is it pH you are checking? If so what pH should it be? I work in a Laboratory at a power station!

The system is the genersys (RM solar) flat panels, and I am sure it was 2.5 bar, (I have it wrote down in the loft), but will check tomorrow.

I see no issue with he system, it has been working great for the last 4 years, I am just wanting it refilling, not redesigning!

 

[eaton]

Doesn't matter what was written, how do you know it's right as I guarantee 2.5 bar is wrong, your looking for anti freeze level basically, you'll ne a refractometer to check , it's advised to check every year, depending on system design and install, system may have not performed properly and atv2.5 I bet it hasn't so might of stagnated and flashed a bit causing quick depreciation of chemical, without sounding rude you really ne to know your stuff with renewables inc anti freeze levels, system set up,etc,

 

[lingwood]

Doesn't matter what was written, how do you know it's right as I guarantee 2.5 bar is wrong, ,

Installers and manufacturer states 3- 4 bag at 20 deg c, I wrote down 2.6 at about 16 deg c.See page 37 below clearly says 2.5 bar

http://www.rmsolar.co.uk/files/onroofmanv2.pdf

Unit has max working pressure of 6 bar.

glycol has been tested at -20, and weather we had last year it got down to -16 with no issues.

 

[ecowarm]

Installers and manufacturer states 3- 4 bag at 20 deg c, I wrote down 2.6 at about 16 deg c.See page 37 below clearly says 2.5 bar

http://www.rmsolar.co.uk/files/onroofmanv2.pdf

Unit has max working pressure of 6 bar.

glycol has been tested at -20, and weather we had last year it got down to -16 with no issues.

I'm only 41 miles away, hopefully you can sort it yourself.

 

[lingwood]

If you where just a bit closer, I am sure I will sort it...its not rocket science! Thanks for the offer.

 

[lingwood]

I am currently in the process of refilling the system! I bought a garden pressure sprayer (5L) and made some fittings to fit the system.

This has allowed me to pressure test the system with air (3bar) and after 1 hour zero pressure loss (GREAT).

I am now about to start filling the system with the fluid, which has been checked as pH 8.9 and all good.

I also bought a drill pump which I plan on using to leave the system in recirculation untill all air is out. This + combination of the pressure sprayer I see as a very good solution.

Oh, and I have extra conformation that this system is 3bar working pressure (pressure relief valve is 6 barg) from both the UK distributer (RM) and manufacture Genersys, who have been in the business alot longer than someone that only got a "certificate" this year ! LOL

 

[lingwood]

Job done!

Simples

 

[eaton]

Mcs cert this year but solar trained a lot longer, oh well good luck especially with gener**** system, as you clearly know more than everyone trained on here I'll leave it with you, bet you don't come back if system blows out fluid next year admitting you might be wrong, I'd never set it above 2 bar, any manufacturers worth their salt will tell you that, if you really want to be specific with pressure, pressure is set depending on expansion vessel height form panels and pump volume but hey let's not give a **** and just stick it at 3, and I can't for the life of me understand not putting £20 worth of new chemical in instead of using a 5 year old one, it's possibly got 2 years tops left. Save yourself some hassle and change it now. But oh I forgot you know best, good luck

 

[lingwood]

No I dont know best, the manufacturer does! and they said everything is OK. Pressures, and glycol.

Why would it all of a sudden change and be blowing fluid out when all the settings are the same as the last 5 years?

Why is it so difficult for you to understand what the manfucaturer states?

The panels etc are rated to 10 bar, the pressure relief valve is rated at 6 bar, therefore a system pressure of 3 bar is well within the system.

Which once again I state it has been at approx 3 bar for the past 5 years with no issue.

Also from basic physics, the higher the pressure the higher the fluid temperature before it starts to boil...which you don't want in a system.

Maybe I might change the fluid in 2 years, it might be 5 years. It all depends on the pH and freezing point of the glycol, both of which can simply be checked with a ph meter and refractomer, both of which I have.

So why change somthing that does not need changing?

 

[lingwood]

i usea tub with glycol in that i put a sumbersible pump in works a treat then pump up pressure using a garden hoselock ive adapted, just leave the pump in the tub for an hour whilst your doing other bits

Thanks, that top tip worked great!

 

[eaton]

Glad I helped.

Also anyone else refilling loads of systems, done 4 in last 8 weeks to 3 left, all by company's gone bust, smart energy is one, they all seem to be from essex

 

[lingwood]

all by company's gone bust,

Slightly off thread, but do you think there will be a major disappearance of solar PV companies on the 13/12/2011?

 

[eaton]

Yes 2 big ones have already gone