Instant Hot Water - The Next Steps

[crozdog]

Hi Guys,

I've picked up an "instantaneous" hot water system that I want to use as a replacement for my HLT. Why? Simple - I don't need to get another 200l drum (for a HLT for big brew days); no more having to wait for an hour or more for water to reach strike temp; sparge water when I want it; & no hassles with logistics when doing big brew days (ever waited on 150+L to heat up in order to sparge?)! It even opens up the possibility of moving to fly sparging instead of batch sparging large batches.

Anyway, back to the unit. It's an older manual Bosch unit (ie no computer controllers) which runs on natural gas (NG). To obtain my desired temp, it should (hopefully) be a matter of simply adjusting the flame & flow rates (in/out/hot/cold). It has a flame adjust as well as a hot & cold "tap" which I think are on the output (I think the unit was used for a shower).

Now to the questions:
- I understand that LPG uses a smaller "jet" size than NG, but how do I determine what size I need to convert to LPG? where can I get them?
- Do I need to run a regulator off the LPG bottle? If so what sort of flow rate is likely to be required? Would an adjustable high pressure reg provide any benefit?
- Do I need a licensed gas fitter to do this sort of work?
- Can anyone recommend where I can obtain reasonably priced inline thermometers & flow meters?

Has anyone done this before?

Any licensed gasfitters in sydney (inner west) care to help out or can you recommend someone licensed to help out in return for a few brews?

Beers

Crozdog

 

[redbeard]

wouldnt it be cheaper to use ng ? its not like we have big brewdays in the park ! your going to need a source of water with pressure ie a tap so .... perhaps a ng outlet is also a pre-req ...

usually gasfitters can do the jet conversion. i think ng needs bigger holes than lpg, so u might need new jets.

if u insist on lpg, then an adjustable hp reg should do the trick. In the interests of a PoC, you could borrow mine

 

[Justin]

Good work Croz, a lot of smaller breweries are using instant hot water systems. Saves the waste of heating more water than you need too.

I'd speak to a gas guy on how to set it up regarding jet sizes, they will really be the only ones to speak to on that.

However, you should be able to easily build an inline thermometer out of a bimetal thermometer and a T-piece. If you want digital you could make a T piece with a compression fitting coming out of it that is a suitable size to seal on the thermometer stem (you may need to step down from say a 1/2" T piece down to a 1/8" compression fitting). Talk to the guys at a decent plumbing/hose fittings place and they'll sort it out for you with the right parts. Anyway, and inline thermometer will be easy.

The flow meter?? No idea sorry.

Good luck with it all.

Cheers, Justin

 

[crozdog]

Redbeard,

Answers 1 by 1:
Q. wouldnt it be cheaper to use ng ?
A. Not when you consider what it'd cost to connect the shed to NG.

Q. its not like we have big brewdays in the park !
A. Why not i say!

Q. your going to need a source of water with pressure ie a tap
A. i am planning to simply hook it up to the garden hose when needed, again cause of the cost to hard plumb in a water source to the shed (& council regs re waste water disposal)

Q. usually gasfitters can do the jet conversion
A. Yeah I know - do you know anyone?

I have found that the unit needs 1.11kPa for NG & 2.75kPa for LPG. Dunno how that sits with reg size, but I might take you up on the POC offer. better talk to a gasfitter first ;-)

Thanks for the info & encouragement Justin. I picked it up for $40 2nd hand & have just seen 1 on ebay for $515 SCORE!!! :super: :super: