Running Instant Hot Water on LPG gas

[zmk1962]

Hey Raiders,

Our 315L offpeak hot water just started to leak - it's done its time.  Anticipating this event I've been considering switching to a gas Instant Hot Water unit - the only problem is we do not have Natural Gas in the street, so I'd have to go LPG and hook it up to our 2 x 45kg cyls that are currently used for cooking, BBQ and some instant room heating. 

Is anyone currently running a gas Instant Hot Water unit on LPG cyls?  I'd be keen to chat to understand your experience - how long do the cyls last etc. 

Just post here or PM me.

Thanks so much.

Cheers Zoran

 

 

[Green Hornet]

Hi Zoran

We had one on a house we recently sold. It was just the wife and I and a gas bottle would last over six months.

Before that we had a gas, storage style tank and the instantaneous system works out heaps cheaper.

I liked the Bosch Hydropower system due to it having a turbine style ignition system, so when you turn the water on the flow over the turbine creates a spark that ignites the gas. Other systems have an electric spark, so not only do you need provide power to the system, but in the case of a blackout, you lose your hot water.

The only downside is it takes a little longer for the water to get hot from your tap, due to the system holding cold water until activated.

I would by another in an instant, however our new home has solar.

[Rebel]

I have a solar hot water system. Best thing I ever did.

[zmk1962]

22 minutes ago, Green Hornet said:

Hi Zoran

We had one on a house we recently sold. It was just the wife and I and a gas bottle would last over six months.

Before that we had a gas, storage style tank and the instantaneous system works out heaps cheaper.

I liked the Bosch Hydropower system due to it having a turbine style ignition system, so when you turn the water on the flow over the turbine creates a spark that ignites the gas. Other systems have an electric spark, so not only do you need provide power to the system, but in the case of a blackout, you lose your hot water.

The only downside is it takes a little longer for the water to get hot from your tap, due to the system holding cold water until activated.

I would by another in an instant, however our new home has solar.

Thanks @Green Hornet, thats exactly the type of advice and experience I was after !   

A new offpeak electric tank is about the same price as a 26L instant gas system.

Annually I am spending about $600 on offpeak electricity service... at my current Sydney gas supplier rates that equates to about 6.6 x 45kg of gas.  So based on your experience I'd be way in front.

21 minutes ago, Rebel said:

I have a solar hot water system. Best thing I ever did.

Hey @Rebel, unfortunately north and west roof space already has solar electricity panels.  Current hot water is on offpeak - so solar generated electricity cannot heat the tank unless I move the hot water tank to prime electricity circuit all the time - which doesn't add up if the tank wants to heat up at night or rainy day as I'd be paying 28c/kwhr.

Cheers Zoran

 

Edited April 29, 2020 by zmk1962

[noelm]

You can buy LPG instantaneous water heaters ready to go.

[zmk1962]

1 minute ago, noelm said:

You can buy LPG instantaneous water heaters ready to go.

Thanks Noel... yup aware of that.  Just want to get a handle on how much gas they consume. What peoples experiences have been. 

[Rebel]

I suggest you ask a couple of experts what to do before you spend $$$$$$$$$$$.

Mine is on off peak, I don't have a problem. The electricity bill is cheap.

[noelm]

I have a mate with his stove and his hot water on LPG, he looked into for weeks before going LPG, but reckons he is miles in front.

[zmk1962]

16 hours ago, noelm said:

I have a mate with his stove and his hot water on LPG, he looked into for weeks before going LPG, but reckons he is miles in front.

Thanks so much Noel.

[Rob81]

I have LPG and it runs both our stove and instant hot water, We're a house of 4, 2 adults and 2 kids. One tank last roughly 3mths, however, in the last 4-5 Months, I've been cooking out side on the gas weber (attached to a separate tank) and the 45kg LPG last a lot longer.

I recommend you look into them instant hot water tanks and see if you can find reviews. The one I have came with the house and sometimes the hot water goes cold for a period and back hot again (and this isn't due to tank being almost empty or empty). I assuming they stuck on a cheap one when the built the house so goes in and out. I have read in some places it can also be due to pressure, if not enough water running through the system it will not turn on but in my case we've not adjusted the water for the pressure to change. Only time its a big issue is having a nice hot shower after a cold fishing session in the middle winter.

[zmk1962]

9 minutes ago, Rob81 said:

I have LPG and it runs both our stove and instant hot water, We're a house of 4, 2 adults and 2 kids. One tank last roughly 3mths, however, in the last 4-5 Months, I've been cooking out side on the gas weber (attached to a separate tank) and the 45kg LPG last a lot longer.

I recommend you look into them instant hot water tanks and see if you can find reviews. The one I have came with the house and sometimes the hot water goes cold for a period and back hot again (and this isn't due to tank being almost empty or empty). I assuming they stuck on a cheap one when the built the house so goes in and out. I have read in some places it can also be due to pressure, if not enough water running through the system it will not turn on but in my case we've not adjusted the water for the pressure to change. Only time its a big issue is having a nice hot shower after a cold fishing session in the middle winter.

Thanks @Rob81 !  So I guess you're concluding he webber is more efficient than the stove inside !  I've read a lot of recent bad reviews on the current Bosch models and only praise on the Rinnai (42 bad reviews from all over the country https://www.productreview.com.au/listings/bosch-optiflow-professional). Which is a bit upsetting cause I liked what Green Hornet said about the HydroPower start that Bosch has on some of their units.  So at present I'm leaning to a Rinnai even though it will mean cold water when there is a power failure (but because we have solar, it will be limited to power failure at night).

I'd be very happy to get 3months out of a tank (house of 3 adults) ... only 4 gas bottles a year !

Cheers and Thanks Zoran

[Rob81]

Yeah a few things about the weber:

1. It heats up much faster than the bloody stove

2. It cooks way better than the stove (I think heat is regulated better than the oven)

3. Uses the gas as Oven feature where the LPG gas Stove/Oven, the oven portion is using electricity and not gas.

Again, the stove came with the house and looks like one of those cheap ones you get out of bunnings. Am hoping to upgrade it one day to and hopefully it makes a difference.

yeah a few factors changed in the house within the last year which could explain why the tank is now lasting longer. For some reason I only noticed other day my kids dont sleep in the shower any more like they used to (30-50min showers to now 5-15min showers). 

Each house would be different. TBH with the stove Im not 100% which is better, either a LPG stove or electric stove as in both worlds you can get some decent ones but I've yet to experience it comparing to traditional gas stoves.

[Rob81]

Main advantage I see is not worrying about running out of hot water as it is instant. And if you run out of gas, usually you're setup with two tanks for when one is finished anyway.

[zmk1962]

Agree. We cook on gas stove now - love the instant heat and it is hotter than electric. We are set up with 2 bottles so there is no extra rent for them. So it’s just the additional consumption of gas that I had to factor in. I’m spending $600 per year on off peak electricity for hot water. That’s 6.6 x 45kg gas bottles. Looks like I’ll be in front. 
cheers Z

[PaddyT]

I ran one for 15 years at my business -swim school so the shower in particular was on ALL the time- i couldnt tell you what the gas burn was because the main pool heater ran off the same two cylinders-mind you my gas bill was usually about 2000 per month from May to Sept when the pool needed most heating and dropped to about 250 per month when it was just showers being run- the unit was still going strong when i sold the business last July and was getting towards the 20 year old mark-it was a Bosch wall mounted . My other experience was in Europe - my wifes apartment used these and this was also the room heating system - it fed hot water into radiators in the apartment in winter- these were also standard fare over there and considered to be very reliable.

[61 crusher]

1 hour ago, Rob81 said:

The one I have came with the house and sometimes the hot water goes cold for a period and back hot again

This problem could come about if it is either incorrectly installed (pipe sizing of gas lack of pressure, more than one appliance used) or another common issue can be a combination of shower head restricter & water supply pressure drop to unit caused by other taps being used or the toilet being flushed 

 

1 hour ago, Rob81 said:

yeah a few factors changed in the house within the last year which could explain why the tank is now lasting longer. For some reason I only noticed other day my kids dont sleep in the shower any more like they used to (30-50min showers to now 5-15min showers). 

That would definitely make a difference as the instantaneous HWS has a high MJ/H gas consumption 

 

1 hour ago, zmk1962 said:

I've read a lot of recent bad reviews on the current Bosch models and only praise on the Rinnai (42 bad reviews from all over the country https://www.productreview.com.au/listings/bosch-optiflow-professional). Which is a bit upsetting cause I liked what Green Hornet said about the HydroPower start that Bosch has on some of their units.

Bummer about that, hopefully one of the manufacturers incorporates a reliable hydropower system into there units because of possible future power failures

Edited April 30, 2020 by 61 crusher

[Green Hornet]

1 hour ago, zmk1962 said:

Thanks @Rob81 !  So I guess you're concluding he webber is more efficient than the stove inside !  I've read a lot of recent bad reviews on the current Bosch models and only praise on the Rinnai (42 bad reviews from all over the country https://www.productreview.com.au/listings/bosch-optiflow-professional). Which is a bit upsetting cause I liked what Green Hornet said about the HydroPower start that Bosch has on some of their units.  So at present I'm leaning to a Rinnai even though it will mean cold water when there is a power failure (but because we have solar, it will be limited to power failure at night).

I'd be very happy to get 3months out of a tank (house of 3 adults) ... only 4 gas bottles a year !

Cheers and Thanks Zoran

As a licensed builder for more years than I care to remember, I have had instantaneous systems installed into most homes I've built. Weather the hydrostatic Bosch or the electric Rinnai systems, I can honestly say I've never had a warranty claim or bad report from any customers of mine.

If they don't have solar, every plumber I know in my area runs an instantaneous, whether it be a Bosh or Rinnai.

What I can add and has been mentioned above, the Bosch does need a little more water running through the system to keep the gas operating than the Rinnai, but still its only a trickle and never bothered me in the 15 plus years I owned one a Bosch.

Its also not uncommon on a very large home to run multiple systems due to the distance between the kitchen and bathrooms. They're comparatively cheap and with my plumber, work out at around $1,200 installed.

[JonD]

6 minutes ago, Green Hornet said:

As a licensed builder for more years than I care to remember, I have had instantaneous systems installed into most homes I've built. Weather the hydrostatic Bosch or the electric Rinnai systems, I can honestly say I've never had a warranty claim or bad report from any customers of mine.

If they don't have solar, every plumber I know in my area runs an instantaneous, whether it be a Bosh or Rinnai.

What I can add and has been mentioned above, the Bosch does need a little more water running through the system to keep the gas operating than the Rinnai, but still its only a trickle and never bothered me in the 15 plus years I owned one a Bosch.

Its also not uncommon on a very large home to run multiple systems due to the distance between the kitchen and bathrooms. They're comparatively cheap and with my plumber, work out at around $1,200 installed.

 We had the Bosch installed and couldn't be happier. When we had no power due to bush fires I simply rigged up an inverter and an old 12 volt battery to trigger the ignition.

[zmk1962]

Fantastic feedback RAIDERS! .... thanks so much - you've helped confirm to me a switch to instant/LPG is the way to go.

Cheers Z

[noelm]

I am going to put a small instantaneous LPG water heater and small cooktop in a granny flat, currently it has a 50l quick recovery and a 2 element cooktop, the small water system uses heaps of power, and heats up and cools down even if no one uses hot water.

[kingie chaser]

I just wish I had the option of gas!

No gas in our building so my electricity bill is pretty high for a single person 1 bdr apartment.

Mind you most of that goes to an electrical 50L hot water service.

I do like the idea of those Rennai instant systems but I have also used some that the water temp changes quite a bit during the length of a shower.

 

If I had the option solar would be what I would go for IF the financial incentives/rebates were still there to be claimed.

Its something more of an investment that is a bit of an outlay at the start but I have known people that are putting power back into the grid & getting credits that come of there electrical bills!!

 

Edited April 30, 2020 by kingie chaser

[Rob81]

There's still rebates on solar. One on installation of panels and then solar plans rebates on adding energy to the grid.

[zmk1962]

Just to close this out.  I'm now not only cooking with gas ... but also showering with gas. Thanks so much to @61 crusher who did a fantastic job installing the Rinnai ... although I'm sure our constant digression to things fishing and boating extended the install time for him.  Top bloke and top job mate - thanks again Dieter !!

As a side note,  I picked up on what @JonD said above and decided to buy a "jump starter with inverter" ... this will be the backup power supply for the gas hot water should there be a power outage at night when I don't have solar power, and as a bonus  I can now use this in the 4wd, or on boat trips. 

All sorted because of Fishraider !!!!

Cheers and Thanks to all.

Zoran

 

[zmk1962]

On 5/4/2020 at 11:11 AM, Rob81 said:

There's still rebates on solar. One on installation of panels and then solar plans rebates on adding energy to the grid.

I have solar installed. You can't run your Electric hot water on your solar electric circuit and off peak circuit at the same time. It's one or the other. 

Cheers Zoran

[zmk1962]

I’m paying $89 for 45kg bottle delivered. That works for me. 
cheers Zoran