Sad to said, you have to forget your plan. The instant heater with pump is not enough pressure for this big shower. The small pump is not strong enough. The big shower require high flow rate at least 2.5bar.

The minimum requirement is storage heater.

For storage heater, the pressure is from the main pipe. And probably not enough also.

For such a big shower, it require 3/4 pipe size. Instead of normal 1\2.

You mean the "storage heater" come with such built in pump can easily take the water pressure, not as strong enough but just right.

??

Good luck. And do let us know here what is the result.

Brought this Rinnai heater after saw your post picture. Really difficult to find.

Will install it this 2day and see how good is it.

"delete"

This post has been edited by ozak: Nov 28 2014, 12:22 PM

Install it yesterday. Take about 2hr. Running very silent compare to the old 1.

Noise level about 55db at max pump running. The shower head flow is not strong as those big type. So if you looking for a strong flow, you will be dissapointed.

The cost:
1) Heater - RM720
2) Plumbing parts - RM5
3) Labour - Free

Here the step by step for those like to DIY.

Time to change the old heater after use for 7yrs. Still run perfectly without any problem. Just change for the safety reason.


Here the new Rinnai heater with pump.



The internal part. Pump at the right, heater left, pump controller on top the pump, heater controller ontop the heater and the connection at the top right.


The diameter of the shower head is 7". Not that big consider the flow is not strong. You won't get a quick shower with this. Use the handheld for stronger flow.


First of all, swicth ON the heater.


Press the test to check the RCD function. Also as switch OFF the heater.


Use multitester to double check. After makesure no power, Switch OFF the heater Switch.


Takeout the wire and tape it with pvc tape. Close the stop cock to the bathroom water. Takeout the inlet piping. Now the old heater can be takeout completely.



Measure the height according to the manual. In this case around 1200mm. Mark and drill a new hole. Screw the heater to the wall.


Continue.......

This post has been edited by ozak: Sep 12 2018, 09:10 AM

Connect the wire to the connector. Makesure the wire secure tight with the screw connector. Cost this heater run at high watt when max. Otherwise the connector will heat up and kaboom.


I put an additional silicon to seal the wire intake hole. Cause the heater from the shower head is a bit near. This is to prevent the water from sipping in and kaboom the heater.


Done for the wiring. Now the plumbing side. I have place the elbow to the inlet heater valve. So I can measure the vertical pipe lenght that need to be cut.


Use sand paper to clean every fitting and pipe that need to be glue. This will clean up the oil and dirt. So the glue can melt the pvc pipe securely. Wipe with clean cloth.


Tape the screw fitting with white seal tape.


The vertical pipe is temporary insert in. Now use the elbow to mark the lenght of the pipe to be cut. Glue all together. In this step, you need to act fast. The glue will cure fast. Plan which fitting to go in first and how to fit in together. Than apply the glue.


The plumbing done. Wait for 1/2hr or longer for the glue to harden. It actually need 24hr to be harden. But since the water pressure not that high, 1/2hr should be alright.


Open back the stop cock. Check for any water leakage. Than turn the heater valve to open. Let the water flow out from the shower head. Check any leakage in the heater side joint. This is important to makesure no water leak out internal. Any water leak, disamssembly it and take the heater to claim. Close the valve and put back the heater cover.


Switch ON the heater switch. Than reset the RCD. If the RCD trip, switch OFF and check the wiring.If everything OK, the heater light will ON.


Continue........

This post has been edited by ozak: Sep 12 2018, 09:11 AM

Don't run the heater first. Push the test button at the heater to check the heater RCD function or not. All this checking is to makesure the safety device function properly.



After all the checking is done, run the heater. Open the valve. The motor will start to run. The strong of the water flow is adjust at the left of the heater. (pump speed) Than turn the heater knob slowly. Wait 1min for the hot water to comeout. Let the heater run for 15-20min to check for any problem.


To turn OFF the heater, turn the heater knob OFF. Wait for the cold water flow out. Than close the valve. The pump will off. I always use this way so the next person use won't get burn. And also prolong the heater lifespan.

Happy happy shower.

This post has been edited by ozak: Sep 12 2018, 09:12 AM

Nope. This is the end piping to the heater. so no different. Need bigger pipe size from the beginning tank side.

Standard plumbing rule for house is 1/2". While the main is 3/4".

What nut reducing?

Thumb of rule, 1/2" is standard plumbing for inside house. Otherwise you have problem with all your tap, faucet, shower head...etc. Use bigger size pipe if you plan properly and understand what you do.

Frankly speaking, it is not really nice. Those flexible hose tangling around at below is a mess. Not your neighbour, even my 1.

I prefer the mixer type with everything running inside the wall.

How the hell going to bath with this thing?

It look more like a water fountain.

This post has been edited by ozak: Nov 28 2014, 03:50 PM

A direct SS pipe joint to the heater from the tap side.

Now look better. Give some paint on the pipe and the trunking. It blend to the wall.



This post has been edited by ozak: Sep 12 2018, 09:09 AM

Yup, it is acrylic sealer. Multipurpose sealer. Apa gap and material also can use. Can get it from ACE.



This post has been edited by ozak: Sep 12 2018, 09:12 AM

Get it from Puchong. The shop look like 1 to die or not die condition. Don't look for big shop.

How hot the water depend on few condition.
1) water temperature inlet
2) water flow speed.

I only turn the knob to half to get the temperature I need consider now the water temperature is a bit cold than normal.(raining season) Pump speed is max.

You need to measure the water temperature only can tell. I will check later what is the best temperature.

If you live in condo, the water pressure should be good enough without the pump. Control the water flow is the only way to get a very hot water.

Your setup seems same as mind. Consider paint the pipe and the wire to blend to the wall. Look much better.

If the inlet not share with the rain shower, there is no problem.

If you direct tap from the existing shower without T joint, that is no problem.