Low Pressure HWC replacement with Mains pressure

Forums › Home Workshop DIY › Low Pressure HWC replacement with Mains pressure

1 | 2

lxsw20

3552 posts

Uber Geek

Subscriber

#3248284 13-Jun-2024 10:33

I don't think the reducing valves are designed to be adjustable, you buy the head height you want and thats it. As others have pointed out, your tap ware also might not be suitable for higher pressure.

tweake

2391 posts

Uber Geek

#3248285 13-Jun-2024 10:34

tritscher:

Yea they just replaced the HWC and left all the original pressure reducing valves.

New HWC

HWC inlet valves

does that have a tray under the cylinder? it should be converted to having a tray.

also it still has the vent pipe so you can't just wind the pressure up. just double check that label and check thats its actually a high pressure. they may have fitted a low pressure model.

i also have a rheem recently installed and it came with the required pressure valve.

tweake

2391 posts

Uber Geek

#3248286 13-Jun-2024 10:35

lxsw20:

I don't think the reducing valves are designed to be adjustable, you buy the head height you want and thats it. As others have pointed out, your tap ware also might not be suitable for higher pressure.

they are adjustable, its just they will have a limited pressure range.

tweake

2391 posts

Uber Geek

#3248288 13-Jun-2024 10:40

Jase2985:

tweake:

my new tank came with the valves. theres no reason not to swap them over. you would have to have some really dubious pipes for them not to handle mains pressure.

Are you forgetting about all the taps shower heads etc with would likely be low pressure only throughout the house. that matters and would be an additional cost to replace at the same time.

no problem here. i have all low pressure gear and no issues. a bit of tweaking of the shower mixer adjusters to balance it. even then you could get away without doing that. all my cold taps have always been low pressure taps at mains pressure. the only tricky thing was adjusting the hot side of the washing machine as that had been opened right up to get more flow at low pressure.

tweake

2391 posts

Uber Geek

#3248292 13-Jun-2024 10:47

Dynamic:

Not wanting to hijack OP's post, but they may have a similar question in mind to me.

We've got a low pressure cylinder and our hot water flow in the bathroom is just over 4L per minute (IIRC). The shower is the most underwhelming that I've come across in a very long time, and I've tried two low flow shower heads without any notable difference in how it feels or how close to the wall you need to stand to get wet. It takes 1 minute and 10 seconds for the shower to warm up when turned on. The AJAX (?) valve is at it's limit, so turning the thumb screw only reduces the pressure.

We'd like to replace the low pressure cylinder with a mains pressure one, while avoiding replacing shower mixers for the moment. Does anyone have experience with this sort of replacement while using a flow restrictor of some sort? If we could get the shower to even 6L per minute would make a big difference, I suspect.

i have no issues with the old shower on mains pressure other than its fantastic.

the only issue i can see is high water usage, but you can just turn the flow down or fit a high pressure shower head. you will probably need to adjust the balance, there is often adjusters on the inlets of the mixer (take handle and shroud off and adjust with screwdriver). washing machine is probably the harder one, that depends on make/model.

Spyware

3761 posts

Uber Geek

Lifetime subscriber

#3248374 13-Jun-2024 11:56

lxsw20:

I don't think the reducing valves are designed to be adjustable, you buy the head height you want and thats it. As others have pointed out, your tap ware also might not be suitable for higher pressure.

They are adjustable (20 to 100 kPa for 7.6 metre head pressure ones), a certain Christchurch plumbing team with unrivaled expertise (on their website) installed a pressure reducing valve (apex branded) on my low pressure cyllinder when header tank developed a leak. They left the pressure on default of 65 kPa, the water went out the vent pipe over a period of 4 hours and eventually leaked through flashing and ceiling. They took no ownership and sent be invoices for after hours and electrician. Their supervisor came to my house the next day and the first thing he said was how is this even possible. I said stupid is as stupid does.

Spark Max Fibre using Mikrotik CCR1009-8G-1S-1S+, CRS125-24G-1S, Unifi UAP, U6-Pro, UAP-AC-M-Pro, Apple TV 4K (2022), Apple TV 4K (2017), iPad Air 1st gen, iPad Air 4th gen, iPhone 13, SkyNZ3151 (the white box). If it doesn't move then it's data cabled.

WWHB

35 posts

Geek

#3248690 14-Jun-2024 07:19

“does that have a tray under the cylinder? it should be converted to having a tray”

This is 100% correct, a tray is now part of the building codes. It’s not compulsory to run a drain from it, as the location may not be suitable. Manufacturers instructions also state a tray to be used.

1 | 2