Converting to main pressure and gas.

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Paul1977

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#198833 25-Jul-2016 08:47

I have an older 1940's single story house, with quite a small hot water cylinder (and no space for a larger one) and uses gravity pressure from a tank in the roof so hot water pressure not great.

I'd like to achieve 2 things.

1. Change hot water to mains pressure.

2. Convert to gas for water heating.

I wanted to get an idea if this is even possible or remotely affordable before approaching a plumber.

Current water cylinder is in a cupboard in the kitchen, and we will be renovating the kitchen probably in the next year so thought it might be able to be done then.

Is it just a matter of getting a mains feed and gas to where the cylinder currently resides, and then the existing internal pipes will be fine to get from their to the hot taps?

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#1597923 25-Jul-2016 09:00

This is quite easily done with a 'califont' type on-demand gas water heater (Renai or Paloma are known brands here). you'll need a gas installation and certification for anything gas, so try find a gas plumber (installer) who does water too?

NB: You can get "licensed" gasfitters and "certifying" gasfitters. Licensed gasfitters can carry out the work on a caravan but can't certify it. They should have a supervisor, a certifying gasfitter, who will certify the work. A certifying gasfitter can certify his own work.

I did this when upgrading my old 1950's bach, but I was also doing the bathroom, and found several older pipes that were leaking in the walls (already).

So... be aware that your older plumbing may well need to be checked for its ability to withstand mains pressure also. I'm reasonably sure any plumber worth their fee would be able to check this out and advise you

frankv

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#1597925 25-Jul-2016 09:04

Also, the mixer on your shower may not be suitable for mains pressure on the hot water... you may need to replace that too.

Paul1977

5052 posts

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#1597927 25-Jul-2016 09:11

PhantomNVD:

I did this when upgrading my old 1950's bach, but I was also doing the bathroom, and found several older pipes that were leaking in the walls (already).

So... be aware that your older plumbing may well need to be checked for its ability to withstand mains pressure also. I'm reasonably sure any plumber worth their fee would be able to check this out and advise you

That would be my main concern I think. I guess the plumbers are the experts, but how do they check for leaking pipes in the walls?

Paul1977

5052 posts

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#1597928 25-Jul-2016 09:15

frankv:

Also, the mixer on your shower may not be suitable for mains pressure on the hot water... you may need to replace that too.

We did the bathroom a few years ago. All the taps/mixers we put in are "all pressure" so meant to work for both low and mains pressure.

PhantomNVD

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#1597930 25-Jul-2016 09:24

Paul1977:. I guess the plumbers are the experts, but how do they check for leaking pipes in the walls?

pressure test?

As I said, mine were old and ALREADY leaking (30-50 years after being installed... fair enough lifespan I guess) so we were redoing the entire house' plumbing anyway, YMMV but still worth getting a plumber/gasman in to quote and see what they say (with a much better knowledge of the building quality and timeframe for your property) and see if they will gaurentee your system for the next 3-5 years after testing and installing?

*edit - as you say your bathroom plumbing is up to spec, this shouldn't even be a problem then... especially if you use the same plumbing firm who will have records of your last job too.

Paul1977

5052 posts

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#1597937 25-Jul-2016 09:34

Thanks for the replies. Sounds like it is certainly a possibility as long as the existing pipes test out OK.

I have no idea how old the plumbing in the house is, no idea if it has ever been redone (we bought the house about 8 years ago). All the pipes I've seen are copper if that gives any indication?

geoffwnz

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#1597942 25-Jul-2016 09:39

Your scenario is pretty much identical to mine. I replaced a cylinder plus header tank with on demand gas hot water. I miss it when I go away.

They took the cylinder out of the cupboard in the kitchen and installed the gas unit on the wall outside the same cupboard, minimising the changes to the plumbing. I went for bottled gas rather than line gas but that's up to personal preference.

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Paul1977

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#1597947 25-Jul-2016 09:50

geoffwnz:

Your scenario is pretty much identical to mine. I replaced a cylinder plus header tank with on demand gas hot water. I miss it when I go away.

They took the cylinder out of the cupboard in the kitchen and installed the gas unit on the wall outside the same cupboard, minimising the changes to the plumbing. I went for bottled gas rather than line gas but that's up to personal preference.

Showing my ignorance, I didn't even know that line gas was an option. Presumably far more expensive to get it to the house though?

With bottles you have two right? So when one runs out does it automatically switch over to the other, or do you need to manually do something?

geoffwnz

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#1597975 25-Jul-2016 10:00

Paul1977:

geoffwnz:

Your scenario is pretty much identical to mine. I replaced a cylinder plus header tank with on demand gas hot water. I miss it when I go away.

They took the cylinder out of the cupboard in the kitchen and installed the gas unit on the wall outside the same cupboard, minimising the changes to the plumbing. I went for bottled gas rather than line gas but that's up to personal preference.

Showing my ignorance, I didn't even know that line gas was an option. Presumably far more expensive to get it to the house though?

With bottles you have two right? So when one runs out does it automatically switch over to the other, or do you need to manually do something?

Depends on if there is a supply in your street. Talk to your energy supplier for supply and cost options is the best bet.

Standard install seems to be two 45kg bottles with a changeover switch which will automatically swap when one bottle runs out. I deliberately turn off the "spare" bottle until the in use bottle runs out then swap them over (close the empty bottle and open the full one). I do that so I get an instant notification that the first bottle has run out (usually by the shower going cold) and as I've had it seemingly backfill the first bottle with gas (actual gas rather than the liquid) from the 2nd bottle rather than cutting over completely.

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Amosnz

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#1598001 25-Jul-2016 10:19

A 1940's house would likely have copper piping internally, its the 80's ish houses you need to watch which have duxquest or similar plastic piping.

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Paul1977

5052 posts

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#1598007 25-Jul-2016 10:26

Obviously it depends on a number of factors, but how long does a 45 litre bottle tend to last for say a 3 person household?

dusty42

117 posts

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#1598015 25-Jul-2016 10:38

I've spoken to the last two plumbers I've had at my place about a similar job - haven't asked for formal quotes yet, but sounded them out for ballpark figure.

Work needed here is removal header tank, primary hot water cylinder and kitchen under-bench cylinder; and replacement with Rheem 27l machine on existing reticulated supply.

They both indicated $3200-$3500, excludes replacement of tapware that needs to be changed from low-pressue type.

Family member paid $5000+ for similar upgrade at her place this year. From what I can tell the extra cost caused by awful underfloor access and the need to install the Infinity out the wrong side of the house - guess it's fair that running new gas and hotwater lines around/across subfloor wouldn't be free.

geoffwnz

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#1598019 25-Jul-2016 10:45

Paul1977:

Obviously it depends on a number of factors, but how long does a 45 litre bottle tend to last for say a 3 person household?

Varies wildly. Also depends on what else you are running off the gas. In summer, just for hot water a bottle can last up to 8 weeks with 2 adults and one or more smaller humans. In winter I've also got a gas fireplace, so if I use that every night then a bottle can disappear in as little as 2 weeks.

I've averaged between 8 and 12 bottles a year for the past 5 years.

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Paul1977

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#1598066 25-Jul-2016 11:02

dusty42:

I've spoken to the last two plumbers I've had at my place about a similar job - haven't asked for formal quotes yet, but sounded them out for ballpark figure.

Work needed here is removal header tank, primary hot water cylinder and kitchen under-bench cylinder; and replacement with Rheem 27l machine on existing reticulated supply.

They both indicated $3200-$3500, excludes replacement of tapware that needs to be changed from low-pressue type.

Family member paid $5000+ for similar upgrade at her place this year. From what I can tell the extra cost caused by awful underfloor access and the need to install the Infinity out the wrong side of the house - guess it's fair that running new gas and hotwater lines around/across subfloor wouldn't be free.

That's helpful, thanks. I was actually expecting bigger numbers than this.

Our underfloor access is pretty bad, basically a person can't really fit. I'm hoping if we do it at the same time as the kitchen then underfloor access may not be required and they can do whatever they need in a wall.

I think our cost would go up a significant amount if we wanted to use the service where they come and refill your bottles in place (rather than swapping them) as we would have to install them on the other side of the house (like your family member) as I believe they need line of sight with their refilling truck. Don't know how feasible this would be unless they can run the gas pipes up an exterior wall and through the roof space rather than under the floor.

I'm pretty sure we don't have gas on our street for a direct line, but will find this out.

Might get someone to quote sooner rather than later now I know it at least sounds feasible.

Talkiet

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#1598109 25-Jul-2016 11:36

caution: Gas hot water is NOT Mains pressure in most places. It's better than a low pressure HWC, but in nearly all places the mains pressure exceeds the capability of the Gas heater units, so the hot water pressure is lower than if you had a true mains hot water system.

I got a Gas system and it's good, but if you want the "cut you in two" mains pressure then Gas won't cut it (Sorry, I had to!)

Cheers -N

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