Replace gas hot water system with electric one?

Hi

My 1 bedder in Brisbane had a gas hot water system, located outside the unit (but covered from sun/wind/rain by wall and roof). It has needed a lot of repair over the years, so now looking at replacing it. My plumber came back with a standard replacement with another gas unit (Rinnai B16) which is an instant system so no tank as I understand. System costs ~$800 plus install.

Any experience or opinion on cheapest and good reliability between a gas unit or switch to electric? Instant system, or with a tank for outside system?

Cheers
Yann

 

No brainer - Instantaneous gas, it will never run out.

Electric, needs to go inside, needs plumbing modifications, requires a separate power circuit, has a 50L storage tank & can run out with a long recovery time.

 

Gas instant has very few problems. Doesnt need lighting, doesnt have a tank that corrodes, etc. For rentals i think the more streamlined the better sometimes.

 

I have gas and instant. Would never go back to tanks again.

 

Gas is not ideal, from an emissions point of view. Electric powered by solar/green electricity is the best in that court. If everything else is electric in the house, it'd be better not to worry about the gas bottle charges as a renter. However if the rest of the house is gas then instantaneous is a good option for space and money for you.

I've personally got a heat pump at home and it is amazing. But I'd not put one onto a rental due to cost. I've not had any issue with gas instantaneous

 

Gas instants tend to last longer and have fewer problems from what I have seen. And they take up a lot less space.

 

Existing gas pipe may need to be upgraded due to greater requirement - instantaneous systems require additional pressure.
Copper piping expensive ...

 

Thanks all for the answers, there is a clear pattern in the responses!

 

We changed to a rinnea around 20 years ago .

never looked back .

just waiting for our electric one at our weekender to die

cliff

 

Anyone using electric instant water heaters ?

 

They're amazing - a steibel eltron 3 phase unit is the goods. Useless for solar consumption unless you've got a 30kw system

 

Only in cafes where there's no room for storage hws.

 

Wow, flash back (thanks for the reminder )

Many years ago in Thailand they had quite small electric units located in the shower area

True instant hot water (unlike "instant" gas that still has to run hot water from the unit/other end of the house while heating the copper pipes along the way with all that water going down the drain, wasted ).

There isn't only the water savings to consider, the plastic insulated copper pipe doesn't need to exist, and when you turn off the hot tap you don't waste all that hot water remaining in the pipe either

In many large apartment complex's there is a hot water ring main, with pumps constantly circulating the hot water so when you turn on the tap it doesn't have to travel 100m before you get hot water, imagine the heat loss and energy cost of running these

*we used to have gas, when we moved home we went to all electric and put on solar panels With an induction cook top and inverter split systems we don't miss gas, elec is just as instant, solar offsets a heap of usage cost, and the biggest cost of having gas/only ONE supply charge

 

Also under kitchen benches where you'd need a ring main or wait an eternity for hot water. Our hot water takes 3 seconds to get from the hws to kitchen and shower. (System is Located directly below both). I've been to friends places where you wait a full minute for the instant gas Hot water to come, this is the issue for large sprawling single storey homes these days with multiple ensuites and only one system.

I've put a few instantaneous under kitchens with good success, but needs prior planning to run anywhere up to 10mm² cabling into the island to power it. Less water wastage, less electricity usage and overall very fast,very hot, hot water. Also cheaper than a zip boiler 4 in 1 that seem like a good idea but also incredibly inefficient long-term. We're incredibly frugal with power thanks to a mild climate and the efficiency of our hot water, which runs in the middle of the day. Even on a rainy day the solar covers it. An instantaneous system wouldn't. Also given the slow shift from exporting to make money to self consumption and the rise of battery uptake, there's very few batteries which would supply the 5+kW some of these instant hws pull.

 

Poor design, tight @rts builder/owners who say the savings are not buying and running 2 smaller units vs time waiting and user dissatisfaction with the larger, poorly located single unit.

 

Suggestion ?
In commercial/industrial the suggestion is multiplatform/units (three phase) electric instant water heaters at various locations?

 

It really depends on the situation - in most situations where in reality, there's not the necessity, as there's ample room for a storage unit, offices with separate tearooms have ceiling spaces or cupboards which can be utilised or under stair spaces etc, industrial buildings the choice is greater eg on top of fire tunnels, on wall brackets at high level, in bathrooms.

Cafès/restaurants/kiosks on the other hand, need boiling water delivered fast and may not have the space available so 3Φ is better suited to their needs even if there's a higher running cost.

 

In Jan this work was carried out in WA IP as temp was flucuating and now it started again....I paid nearly $450 and now same company (quote arranged by PM) asking for bit more than $500 and here is the spill from them:-

• they have now suggested to install a temping valve (to cap temperate to 50 degrees). The cost of this is $503.80. I mentioned to the supervisor that this should have been suggested at the beginning instead of a service & he said at the time of them completing the service & leaving the property, the water temperature was not fluctuating. I have never had this type of unit installed at a property I manage before so I haven’t had this experience unfortunately. He has mentioned the below:

“We know the unit is in good working order, I would not suggest replacing the unit as the same issues would present, unless a different style unit was installed. If too much cold pressure is added this will counteract the hot water pressure. There should be no further issues present, our techs can show how to correctly operate the hot water correctly. With there being high temperature at the moment passing through the unit, when too much cold is added, this will cut out the unit, restrictors in the fixtures is also a contributing factor to this also. The tempering valve does limit the temperature to 50 degrees, once the restrictors have been removed, this should all be fully functional.”


I really do not want to use this contractor as less than 60 days the problem came back!!!

Any one who knows hot water system or have been through is it worth changing the system....i can try to find out the age of system from PM as she was the PM for vendor...

 

Your PM is talking out of their @rts.

If you have a mains pressure hws (not a gravity tank up in the roof space), you can not adjust the pressure only the volume by turning on the taps.

Most of the items listed in the attachment are maintenance - cleaning aerators (twice), replace missing restrictors, grease screws.

Sounds like they couldn't replicate the issue.

A tempering valve will prevent scalding if set to 40°c but won't stop fluctuations below the set temperature.