[Dave Willis]

Has anyone got one as a van mount? I think Gardiners call it a PRF-RO these days. It has an automatic shut off built in. I'm interested to know how you fixed it inside the vehicle etc, Outside ports? Float valve?

[Spruce]

Has anyone got one as a van mount? I think Gardiners call it a PRF-RO these days. It has an automatic shut off built in. I'm interested to know how you fixed it inside the vehicle etc, Outside ports? Float valve?

The old Merlin isn't best known for being an efficient r/o. It started life as an under counter kitchen water purifier in American kitchens. It didn't have to be efficient. My mates Merlin (he has had 2 of them) only had a 90% rejection rate from new. So his resin costs were high. His waste to pure ratio was also around 5 waste to 1 pure. He fixed that by adding a gate valve to the waste line to throttle that back which improved his rejection rate a little. But his resin costs are still much higher than mine from the same water supplier.

I had a trailer with 3 x 125 liter tanks mounted on it. The ball valve was mounted on the side so the float could use the extra space in the filler lid area to operate in.  Doing it this way increased the level of water in the tank/s.

I would tend to follow along the lines of what PureFreedom does using a 4040 with a float level cut off switch and normally off solenoid valve.
They also use a 4 connector van port. The first two are outlets for the pumps (twin operator) and third is an inlet for the r/o and the 4th being the waste for the r/o to be hosed to the closest drain.

https://www.grippatank.co.uk/2-man-grippahose-delivery-ro-double-valved-stainless-steel-underport

The plastic connectors are cheaper
https://www.grippatank.co.uk/4-port-bumper-underport-plate

My mate fitted a sediment prefilter on the inlet to save his carbon block. Our water is terribly laden with sediment.

[Matt.]

I used the Merlin for a while even bought a second, but truth is its just a bit slow, at best I would get 1 ltr per minute from them with major waste.

At present am double DI with no ro, drawing water in at 75 from tap, but will be picking up a 4040 when I get round to it. These are by far more efficient and can be fitted to the frame of tank easy enough

[8weekly]

I used the Merlin for a while even bought a second, but truth is its just a bit slow, at best I would get 1 ltr per minute from them with major waste.

At present am double DI with no ro, drawing water in at 75 from tap, but will be picking up a 4040 when I get round to it. These are by far more efficient and can be fitted to the frame of tank easy enough

There's less waste with a Merlin than a 4040, or certainly no more waste with a pump.

[Frankybadboy]

I used the Merlin for a while even bought a second, but truth is its just a bit slow, at best I would get 1 ltr per minute from them with major waste.

At present am double DI with no ro, drawing water in at 75 from tap, but will be picking up a 4040 when I get round to it. These are by far more efficient and can be fitted to the frame of tank easy enough

There's less waste with a Merlin than a 4040, or certainly no more waste with a pump.

really !!!!!! i be surpised with that,and your be the 1st to say it,

merlin are know for high waste,and high tds out put, and if you aint got  high pressure forget a merlin

[8weekly]

I used the Merlin for a while even bought a second, but truth is its just a bit slow, at best I would get 1 ltr per minute from them with major waste.

At present am double DI with no ro, drawing water in at 75 from tap, but will be picking up a 4040 when I get round to it. These are by far more efficient and can be fitted to the frame of tank easy enough

There's less waste with a Merlin than a 4040, or certainly no more waste with a pump.

really !!!!!! i be surpised with that,and your be the 1st to say it,

merlin are know for high waste,and high tds out put, and if you aint got  high pressure forget a merlin

Speak to June at Gaps. When I bought my 4040 she said not to expect less waste with it. If anything more waste - 70/30 she said would be right.
Higher tds is right though, but starts at about 95%.

[Dave Willis]

I've always heard Merlins were poor on waste. I might have access to free water so waste wouldn't be an issue. Second hand 4040 housing with a low pressure membrane might be a faster option.

[Matt.]

Like yourself I have access to free water, when using the Merlin ( no booster pump )  I was getting 1 ltr per minute of water around 010 - 014, pretty decent pressure from tap, at the time I was only using a 350 tank but would have to leave van parked there for some time to fill

If am right u can alter the flow on 4040 to waste/pure so can set at an accceptable level,  I would be More than happy having more water at say 020 than less water at 009 as water still has to pass DI

[Spruce]

I used the Merlin for a while even bought a second, but truth is its just a bit slow, at best I would get 1 ltr per minute from them with major waste.

At present am double DI with no ro, drawing water in at 75 from tap, but will be picking up a 4040 when I get round to it. These are by far more efficient and can be fitted to the frame of tank easy enough

There's less waste with a Merlin than a 4040, or certainly no more waste with a pump.

really !!!!!! i be surpised with that,and your be the 1st to say it,

merlin are know for high waste,and high tds out put, and if you aint got  high pressure forget a merlin

Speak to June at Gaps. When I bought my 4040 she said not to expect less waste with it. If anything more waste - 70/30 she said would be right.
Higher tds is right though, but starts at about 95%.

Mine has been running at 50/50 for the past 5 years. It's still producing at 98% efficiency.  HF5 membrane and 50psi water pressure with no booster. I'm happy with that.

Yesterday tap tds 106, r/o pure output before di 2ppm.

.

[8weekly]

I used the Merlin for a while even bought a second, but truth is its just a bit slow, at best I would get 1 ltr per minute from them with major waste.

At present am double DI with no ro, drawing water in at 75 from tap, but will be picking up a 4040 when I get round to it. These are by far more efficient and can be fitted to the frame of tank easy enough

There's less waste with a Merlin than a 4040, or certainly no more waste with a pump.

really !!!!!! i be surpised with that,and your be the 1st to say it,

merlin are know for high waste,and high tds out put, and if you aint got  high pressure forget a merlin

Speak to June at Gaps. When I bought my 4040 she said not to expect less waste with it. If anything more waste - 70/30 she said would be right.
Higher tds is right though, but starts at about 95%.

Mine has been running at 50/50 for the past 5 years. It's still producing at 98% efficiency.  HF5 membrane and 50psi water pressure with no booster. I'm happy with that.

Yesterday tap tds 106, r/o pure output before di 2ppm.

.

You see I'm told 70/30 by the "expert". I'm on my second membrane in a year, so I've not been too impressed to date.

[p1w1]

^^ something wrong there i run the same waste to pure with a tds of anything from 500-580ppm gets it down to about 14-17ppm before DI been like that for nearly a year now. I also have a booster pump running at 80psi. Although you probably use more water then me i would have thought.

[8weekly]

^^ something wrong there i run the same waste to pure with a tds of anything from 500-580ppm gets it down to about 14-17ppm before DI been like that for nearly a year now. I also have a booster pump running at 80psi. Although you probably use more water then me i would have thought.

About 1,000 litres a day, so not massive consumption.

[p1w1]

^^ something wrong there i run the same waste to pure with a tds of anything from 500-580ppm gets it down to about 14-17ppm before DI been like that for nearly a year now. I also have a booster pump running at 80psi. Although you probably use more water then me i would have thought.

About 1,000 litres a day, so not massive consumption.

I'm about roughly 500-600 a day 4-5 days a week on average.