Replacing and shifting hot water cylinder - mains or low pressure?

[Rhino]

Before renovating the bathroom and kitchen we need to replace our old hot water cylinder. It's currently in a cupboard in the kitchen, the plan is to put a new cylinder in the ceiling space above the bathroom (which is next to the kitchen). I'll create a hole in the bathroom ceiling for the cylinder to go up through, as the bathroom will be relined during its renovation anyway. Then we'll gain a whole lot of space in the kitchen.

I have to admit I'm confused with mains pressure vs low pressure and I have no idea which to buy. Is it simply a matter of how much pressure you like in the shower?

Another thread mentions that mains pressure cylinders will only last 10 years - that pretty much rules it out in my case, as replacing the cylinder would require a bit of demolition and reconstruction every 10 years. But as I understand it low pressure is the less desirable option, with lower shower pressure and limited choice in tapware. (In fact, if I have a mains pressure cylinder put in, will I need to replace all the tapware in the house straight away?)

This is for our PPOR.

[Keithw]

If you are changing from low pressure to high, then you may find any mixer taps need to be changed, which can include the shower.
Seperate taps should be ok

In addition there are water temp safety valves that are likely to be needed due to new regs and a different pressure regulator (low pressure systems use a Nefa valve)

So it is not just a matter of cylinder replacement, I suggest you talk to a plumber & get some quotes.

if putting the cylinder in the ceiling, you will also need to consider weight loading (180litres of water weighs 180 kg plus the weight of the cylinder) so needs to be over a supporting wall.
There will need to be an overflow tray with a waste pipe going somewhere, which can be fun getting out from roof spaces.

You should also check for any special building regs. eg cylinders on the floor need to be strapped in place so they dont move in an earthquake

[Knott]

If you have a low pressure tank/ system and you don't want to go to the cost of a high pressure tank and fittings you can install a Hot Water Boost Pump which will allow you to use a low presure tank and give higher water pressure and you still dont need to upgrade you taps , just do a search on trade me for Hot Water Boost Pump

[Rhino]

Can anyone recommend a good cost effective plumber in Christchurch?

I've decided to get 3 quotes:
1. to install a new cylinder in the ceiling
2. to install a new cylinder in a different corner of the kitchen
3. to install an outdoor hot water heat pump

Mains pressure in any case. I'll way up the costs and pick the best option.

[Rolf]

We just replaced our old low pressure cylinder with a mains pressure one. You won't regret it!
We also put our new cylinder under the house and so will gain some extra space when we come to remove the old one.
Also, we had no taps that needed replacement to suit the higher pressure. Got a couple of small leaks though from poorly installed shower heads which was quickly fixed. So watch out for leaks in the first couple of days if you do decide to go for mains pressure.

Not sure about having a cylinder in the ceiling space though as you are considering. Would prefer it to be easily accessible.

[rockran]

What about leaks that you cannot see (pipes in the walls) ? Won't that be expensive to fix later ?

[Rhino]

Yeah, there will be pipes in the wall no matter where the HWC is put, but the ceiling idea sounds like more hassle than it's worth - I wish we had space under the house for it!

Those builderscrack links are just what I needed, I'm going to post on there and see what happens.

Thanks for the mains pressure endorsement Rolf. =) Did you find the building consent process to be straight forward and cost acceptable (if it was needed)?

[Rolf]

No building consent needed as far as I know.

[rockran]

so has anyone who replaced a HWC with high pressure had problems with leaks from pipes in the walls ?

[Green Fish]

I've heard of it happening, but with decent couplings and piping, properly fitted, it should not be a problem.

One point: You are moving the hot water cylinder up, so gravity creates its own pressure on any water going down. The higher up you move the cylinder, the higher the pressure at the shower head.

[Rolf]

so has anyone who replaced a HWC with high pressure had problems with leaks from pipes in the walls ?

Our leaks were inside the wall, behind shower heads. It was not the pipe itself leaking though, only dodgy connections to the shower mixer. I think it would be very rare for the actual pipes to leak.

If you check around, and especially under, the house in the week following the installation you should quickly see if any wet spots develop.

[MikeO]

gas?

have you considered gas? ie rinnai infinity or similar. Mains pressure, unit is outside so you would be able to access it, heaps cheaper to run than electric as you only heat the water when you use it. I've replaced 3 electric cylinders for exactly these reasons and wouldn't use anything else

[Rhino]

Well my first impression of builderscrack.co.nz is very positive - I posted the job on Tuesday night and by this morning I'd already had 2 plumbers come around to have a look.

This is in contrast to last week when I picked a random plumber out of the phone book (with a professional looking ad) and called them, to be told something along the lines of "the boss is away for a couple of weeks, he'll phone you back then to arrange a time".

The first plumber this morning was very positive about all 3 options. He said there wouldn't be much difference between options 1 and 2, and is confident that the ceiling space is a good option. He is quoting the 3 options for me.

The second plumber initially ruled out all options, saying gas was the only way to go (which was interesting, as he is unable to do a gas installation). With some coaxing he agreed that there wouldn't be much difference in price between options 1 and 2 and (like the 1st plumber) assured me that a HWC in the ceiling is safe and nothing to worry about from a maintenance perspective. He reluctantly agreed to quote on the ceiling option (he hadn't heard of a hot water heatpump, so stayed away from that option).

But now I'm quite interested in the gas option! (thanks MikeO, you've backed up what I was told this morning). I don't know why I didn't consider gas before? And my wife is excited by the prospect of gas cooking.

Plumber2 suggested a gas fitter, who I phoned twice this morning and left a message with but have not heard back from.

So same question as before, can anyone recommend a good cost effective gas fitter in Christchurch?

[Rhino]

consent for gas?

MikeO, did any of your gas conversions require council consent?

It probably depends on which part of the country one is in.

[MikeO]

no consent required as I understand it.

MikeO, did any of your gas conversions require council consent?

It probably depends on which part of the country one is in.

Nope definitely no consent required in christchurch - I checked this with the council the first time I did it as I didn't believe the bloke in the shop who sold it to me. I'm pretty sure there is no consent required anywhere in NZ but I'm sure dealers would tell you and you could check with council