[AuRavelling79]

PRF RO update.

Okay so here we are 8 months in and on original membranes.

Today TDS 235 (lower than normal) in. 12 out. 1 litre per minute of pure produced. Input pressure 75psi.

The added 10" sediment filter seems to be prolonging the life of the carbon block filter.

[billy08]

That's really good, I bought this over a year a go and its performance as been bad to say the least.
I have tds in of about 280 and it has never been lower than 15 after ro and reaching 30 in several weeks.
Ive changed membranes 3 times in the last 10 months!
The last membranes were put in on 23/11 and tds is now 24, I have 2 smaller filters trying to protect the larger carbon filter which I have to change every 3 weeks!
We use about 2000 litres of pure a week.
The whole thing is a nightmare but im stuck with it unless I spend a load of wedge on some other system.
Any suggestions, anyone.

[Spruce]

That's really good, I bought this over a year a go and its performance as been bad to say the least.
I have tds in of about 280 and it has never been lower than 15 after ro and reaching 30 in several weeks.
Ive changed membranes 3 times in the last 10 months!
The last membranes were put in on 23/11 and tds is now 24, I have 2 smaller filters trying to protect the larger carbon filter which I have to change every 3 weeks!
We use about 2000 litres of pure a week.
The whole thing is a nightmare but im stuck with it unless I spend a load of wedge on some other system.
Any suggestions, anyone.

At the moment its working at removing 91% of the impurities in the water.  A fellow windie is on his second Merlin and they never achieved better than 90% from brand new.

He helped it a bit by fitting a 3/8" ball valve onto his waste line to restrict the amount of waste going to the drain. So instead of 5 liters waste to 1 liter pure its now about 1 liter waste to 1 liter of pure. (That 3/8" ball valve must never be fully closed.)

What's your tap water pressure?

What is your pure to waste ratio? In other words, how much water in liters goes down the drain to make 1 liter of pure?

.

[dd]

According to his post tap pressure is 75psi. To only get tds of 012 IMO is poor.

My 300gpd ro-man unit is much more efficient and only runs on 55psi. I usually get 004 with a 200tds input.

[Spruce]

According to his post tap pressure is 75psi. To only get tds of 012 IMO is poor.

My 300gpd ro-man unit is much more efficient and only runs on 55psi. I usually get 004 with a 200tds input.

I agree. My personal opinion is that these Merlin and its predecessor r/o's aren't up to window cleaners requirements. They were designed for kitchen under counter r/o's in American kitchens (third tap) and do a great job for the purpose they were designed.

For window cleaning we need to strip out every last ion of dissolved solids or as close to that as possible from our tap water.

The first r/o we had was a RoMan type 450GPD and with a tap water tds of 250ppm - pure output was 4ppm - 40 psi water pressure.
Upgraded to 4040 with HF5 membrane and tap water tds 99 - 125 ppm - pure output is 2ppm - 50 psi water pressure. (Tds came down with relined pipes and pressure went up at the same time.)

That fellow windie with the Merlin was initially 15ppm pure but is down at 10ppm now.

I would recommend billy08 throws in the towel with his current r/o and replaces it with a 4040.

.
 

[billy08]

3 litres of waste to 1 pure with 55psi water pressure.
Thanks for the suggestion of changing to 4040 but why would this be better.
I used to have 200gpd which cost next to nothing to run but couldn't produce quick enough, this is the pay of I suppose.

[Spruce]

3 litres of waste to 1 pure with 55psi water pressure.
Thanks for the suggestion of changing to 4040 but why would this be better.
I used to have 200gpd which cost next to nothing to run but couldn't produce quick enough, this is the pay of I suppose.

No its not the payoff. A 4040 will produce the same quality of water your 200GPD did and faster (probably twice as fast) than the one you have now.

[dd]

According to his post tap pressure is 75psi. To only get tds of 012 IMO is poor.

My 300gpd ro-man unit is much more efficient and only runs on 55psi. I usually get 004 with a 200tds input.

I agree. My personal opinion is that these Merlin and its predecessor r/o's aren't up to window cleaners requirements. They were designed for kitchen under counter r/o's in American kitchens (third tap) and do a great job for the purpose they were designed.

For window cleaning we need to strip out every last ion of dissolved solids or as close to that as possible from our tap water.

The first r/o we had was a RoMan type 450GPD and with a tap water tds of 250ppm - pure output was 4ppm - 40 psi water pressure.
Upgraded to 4040 with HF5 membrane and tap water tds 99 - 125 ppm - pure output is 2ppm - 50 psi water pressure. (Tds came down with relined pipes and pressure went up at the same time.)

That fellow windie with the Merlin was initially 15ppm pure but is down at 10ppm now.

I would recommend billy08 throws in the towel with his current r/o and replaces it with a 4040.

.

I agree, am surprised that Alex and Grippa sell these as their preferred system.

[Spruce]

According to his post tap pressure is 75psi. To only get tds of 012 IMO is poor.

My 300gpd ro-man unit is much more efficient and only runs on 55psi. I usually get 004 with a 200tds input.

I agree. My personal opinion is that these Merlin and its predecessor r/o's aren't up to window cleaners requirements. They were designed for kitchen under counter r/o's in American kitchens (third tap) and do a great job for the purpose they were designed.

For window cleaning we need to strip out every last ion of dissolved solids or as close to that as possible from our tap water.

The first r/o we had was a RoMan type 450GPD and with a tap water tds of 250ppm - pure output was 4ppm - 40 psi water pressure.
Upgraded to 4040 with HF5 membrane and tap water tds 99 - 125 ppm - pure output is 2ppm - 50 psi water pressure. (Tds came down with relined pipes and pressure went up at the same time.)

That fellow windie with the Merlin was initially 15ppm pure but is down at 10ppm now.

I would recommend billy08 throws in the towel with his current r/o and replaces it with a 4040.

.

I agree, am surprised that Alex and Grippa sell these as their preferred system.

Alex has everything is stock to build a 4040 in parts including membrane, 4040 housing and 20" prefilter housings.

.

[8weekly]

I've not been hugely impressed with my 4040. I gather from Gaps I screwed up the membrane by having the waste ratio wrong. Within two weeks the tds went from 6 to 14. Input is around 300.

[dd]

Spruce

Yes, but it is the only complete RO system Alex sells and the systems from Grippa (designed by Alex) use the Merlin style RO.

[Spruce]

Spruce

Yes, but it is the only complete RO system Alex sells and the systems from Grippa (designed by Alex) use the Merlin style RO.

The Merlin and its predecessor are low cost plug and play r/o systems that need the basics to get into water production at a reasonable initial price. Because they only need a ball valve to switch the complete r/o off when the storage tank is full, buying additional equipment isn't going to add much to the initial cost outlay.

Most window cleaners start off on a budget and tend to make their decision on price rather than account for the long term cost savings.

These r/o's aren't as efficient as window cleaners need them to be IMHO, so a windie using these r/o's will use more resin polishing off the remaining tds to make the water pure. But he will be buying the extra resin needed from the money he is earning.

Years ago the price of a 4040 was much more expensive than a Merlin, so it might have taken a long time before the initial costs and running costs balanced out.

I don't know why Alex past over the EZ r/o systems to Grippatank TBH.  I can only imagine it was a business decision. The EZ r/o system is what is included in the complete tank system they sell, although they also sell the PRF as a stand alone r/o filtration unit.

The PRF membranes aren't the same as the 4040 or 4021 membranes and aren't interchangeable as far as I know. If they were then Alex wouldn't stock the membranes separately.

Merlin membrane
 
http://gardinerpolesystems.co.uk/all-products/pure-water-systems/water-treatment/reverse-osmosis-membranes/merlin-prf-ro-membrane-ge-genuine-membrane.html
 
 4021 membrane

http://gardinerpolesystems.co.uk/all-products/pure-water-systems/water-treatment/reverse-osmosis-membranes/axeon-hf5-4021-21-ro-membrane.html

4040 membrane

http://gardinerpolesystems.co.uk/all-products/pure-water-systems/water-treatment/reverse-osmosis-membranes/axeon-hf5-4040-40-ro-membrane.html

There are other suppliers out there who also sell PRF r/o's. GAPS water and Window Cleaning Warehouse are a couple.

.

[Tosh]

Im one of those guys wo has used a 4040 for the last 4 years or so and have had nothing but problems with it.

Different membranes - same problem, they only last 6 months. I replace a membrane, it works for a while, water quality deteriorates so its only removing 70-75%; then I try a different one either HF5 or HF4 and the same thing.

Ive bought one of these Pentairs from Alex and have still got an unopened bag of resin sat in the shed from 2 1/2 months ago. Its currently chucking out water at 14ppm with a tap-water supply of 300.