Help making a re circulation pump

[rich1985]

https://www.screwfix.com/p/compression-equal-couplers-15mm-2-pack/95828
this will connect two lengths of 15mm copper pipe. The “compression adapting male coupler 15mm x 1/2 inch” in my list (item 3) will connect tap out to copper pipe. Fit tap IN directly to pump OUT.
You’ll need one of these to cut copper pipe.
https://www.screwfix.com/p/3-28mm-manual-multi-material-pipe-cutter/49428

Thank you so so much for your advice. I'm going to take this away and digest it and come up with a plan of action.

 

[The-Engineer-That-Brews]

By the way, it can sometimes be hard to do up those 15mm ‘compression’ fittings tight enough to make them fully watertight... I find it helps to wrap a couple of turns of plumbers PTFE tape (also cheaply available at ScrewFix) around the threads first :-)

 

[Buffers brewery]

By the way, it can sometimes be hard to do up those 15mm ‘compression’ fittings tight enough to make them fully watertight... I find it helps to wrap a couple of turns of plumbers PTFE tape (also cheaply available at ScrewFix) around the threads first :-)

Careful, don't over-complicate/over-engineer this

 

[Ashman]

I have the solar pump but would like to put a filter on it. So plan would be run a brew in a big sitting on a wire sieve and then put some mesh on the pump inlet screwed under the barb hose tail. However, presumably this would restrict the pump flow at the inlet and then pump would fail ? (When I put mesh over a syphon it worked but was slow).

 

[Buffers brewery]

If your grain is in a (brew-in-a-) bag you shouldn't get too much, if any, grain through to block the filter or pump. The solar pumps I use are pretty hardy and provided they are primed they survive being stalled (wouldn't try that for too long). You know when they're struggling as the sound changes noticeably.
Have you experienced pump blockage or are you just being cautious?

 

[Ashman]

If your grain is in a (brew-in-a-) bag you shouldn't get too much, if any, grain through to block the filter or pump. The solar pumps I use are pretty hardy and provided they are primed they survive being stalled (wouldn't try that for too long). You know when they're struggling as the sound changes noticeably.
Have you experienced pump blockage or are you just being cautious?

Just cautious. I did hear the sound change when running and it looked like possible air bubbles in the hose. I don’t think it was cavitation though as that not a problem for homebrew?

I have 6mm ID silicone hose too but I’m now looking at 1/2 female bsp to 10mm compression instead of hose connectors to maybe rig it up in 10mm copper. Threads and compression fittings compared to barb, cable ties and silicone hose....

 

[Buffers brewery]

If you've got bubbles in the feed pipe to your pump, the pump is pumping out faster than the wort is flowing in so you need to slow it down a bit. Either fit a tap on the OUT side of the pump and close it down a bit or use a model railway controller (as I do) to slow the pump speed.

 

[Ashman]

If you've got bubbles in the feed pipe to your pump, the pump is pumping out faster than the wort is flowing in so you need to slow it down a bit. Either fit a tap on the OUT side of the pump and close it down a bit or use a model railway controller (as I do) to slow the pump speed.

Cheers. I’ve found an LED dimmer. I need to check but think it will be Pulse width modulation(PWM). I don’t know train controllers but didn’t think they were PWM. More like scaletrix controllers. That brings back memories of burning smells.

 

[Buffers brewery]

Basic model railway controllers aren't PWM just variable voltage. I'll be interested to see if your LED controller will pass enough current to run the motor. Do you know what it's power rating is?

 

[Ashman]

Basic model railway controllers aren't PWM just variable voltage. I'll be interested to see if your LED controller will pass enough current to run the motor. Do you know what it's power rating is?

The power rating is listed as 24w 2A at 12v. Though I almost fell off my chair because I don’t think it’s going to pass more than 0.5-1A at 12V.

 

[Buffers brewery]

The power rating is listed as 24w 2A at 12v. Though I almost fell off my chair because I don’t think it’s going to pass more than 0.5-1A at 12V.

Wow! That's plenty. Let's know if it works out.

 

[The-Engineer-That-Brews]

Apologies if I'm teaching my Grandmother to suck eggs, but those solar pumps are not simple 'the DC current goes into the windings and off you go' jobs. They are brushless motors with some built-in control electronics.
I have experimented with controlling their power by backing off the voltage, but they don't like it much; and don't think a PWM supply would be a good idea at all.

In an case, in my humble opinion with a recirculation pump you want to keep the impeller running at full speed anyway so that it can smash through any bits of crud that get in there.
Consequently (and apologies for being a broken record on this) my preferred method of controlling the recirculation rate is to fit a little tap in parallel with the pump, i.e. via tee connectors immediately before and after it. Tap fully closed means 100% of the pump flow rate goes round the recirculation circuit; but the more you open the tap, the less (recirculation) flow you get.

 

[Buffers brewery]

I can only speak from my experience over the last 12 months of using my solar pumps.

I use a model railway controller that varies the voltage and it works fine. There is a setting below which the pump doesn't run but that is below the slowest rate you'd want to run anyway.

 

[Subtle Duck]

I'm looking at finally getting around to adding a pump to my inventory. Have any of you used these cheaper pumps for recirculating during the boil or whirlpooling? If so, do they cope with the heat well?

 

[Buffers brewery]

The pumps I use (see above) work fine at boil temperatures. Probably could do with a few more l/min for whirlpooling but fine for recirculating.

 

[Wynne]

In an case, in my humble opinion with a recirculation pump you want to keep the impeller running at full speed anyway so that it can smash through any bits of crud that get in there.
Consequently (and apologies for being a broken record on this) my preferred method of controlling the recirculation rate is to fit a little tap in parallel with the pump, i.e. via tee connectors immediately before and after it. Tap fully closed means 100% of the pump flow rate goes round the recirculation circuit; but the more you open the tap, the less (recirculation) flow you get.
[/QUOTE]

I’m intrigued by your suggestion. If you open the tap fully, will you get 100% flow going around the pump bypass circuit and none in the recirculation circuit or will that, as I suspect, depend on the power of the pump and the configuration of the two circuits? lf I’m correct, to achieve 100% control over the recirculation circuit, wouldn’t one need a second valve after the bypass tee on the flow side to force all flow from the pump back around the bypass circuit?

More broadly, I’m thinking of adding a HERMS to my setup so would be interested in where best to place the wort/mash temperature probe and how best to control the pump. Any thoughts on fitting a heat exchange coil in the HLT vs a smaller, separately heated HERMS vessel would also be welcome.

 

[Buffers brewery]

I’m thinking of adding a HERMS to my setup so would be interested in where best to place the wort/mash temperature probe and how best to control the pump. Any thoughts on fitting a heat exchange coil in the HLT vs a smaller, separately heated HERMS vessel would also be welcome.

I’ve just posted on another thread you might find interesting.
https://www.thehomebrewforum.co.uk/threads/herms-pid-control.91513/
I fitted my first HERMS coil inside my HLT/Kettle but as it was gas heated was difficult to control. Now I have a separate electric heated HERMS tank and I just control the water temperature to achieve the desired mash temperature.

 

[Ashman]

HERMS is lost on me. It looks like if I added a kettle and copper coil , switched pump of temperature control I could change from RIMS to HERMS. But I haven’t done the calcs and suspect it wouldn’t work based on the pump litres a minute.

 

[Wynne]

HERMS is lost on me. It looks like if I added a kettle and copper coil , switched pump of temperature control I could change from RIMS to HERMS. But I haven’t done the calcs and suspect it wouldn’t work based on the pump litres a minute.

What is your setup @Ashman?

 

[Ashman]

What is your setup @Ashman?

At the stage it’s very much work in progress as I can’t brew or test properly. There are a few flaws, wattage of the kettle too high for controller, silicone mesh seal is a pain to fit, water has to go upwards to flow to pump, Controller needs mounting / placement, etc

The alternative mode I thought would be to run the pump off the temperature controlled iec outlet and pump wort through a 10mm copper pipe in a kitchen kettle. I would get female 1/2 bsp to 10mm compression connectors.

Alternatively I could just hack the thermowell into the sightglass and leave all the pumping bits and bobs out.I can also switch the controller out into the fermentation tank to run a small heater.

2500w 20L kettle,​

Old grainfather controller,​

Grainfather wortometer (essentially has a in line thermowell),​

Silicone pipe 6mm ID,​

Solar pump , silicone aquarium hose and dc connector​

Pvc tube ( will switch to cutting up the silicone pipe),​

Old sight glass from original urn with factory installed zip ties,​

Stainless mesh sieve held in place with silicone seal​

12v power supply (i need to check amperage),​

220v socket to IEC 50cm​