if u feel a lot vibration noise, need plumber check and relocate to a better position if possible, depending on ur ceiling design.

If purchase from me, i always give an anti vibration pad to reduce noise, if a little vibration is normal. if whole house can hear loud noise then need to check

Hi sifus

I have finally gone through 64 pages of reading on this Grundfos thread.
I have a problem which I cannot totally brain.

My water tank is on the 5th floor of the apartment and my unit is on the 3rd. Problem is the water outlet from the water tank to my unit needs to climb over the wall and according to the contractor/plumber, there is a much higher risk of air trap when the water level in the tank runs lower than the tank outlet which supply water to two bathrooms. Means, the 'climbing' can cost a lot of problems. He said when there is air trap, there will be no water flow from my pipe as it will be blocked. He asked me to instal water pump which costs RM1800. He said, water pump can draw out the air trapped in the pipe so water flow to the bathrooms will be normal again. Is this true?

The water tank area is a common area where all water tanks to other units are also located. If I need to install water pump, I don't think I can install it next to my tank. Would it make sense to install the pump in my balcony which is on the 3rd floor then? Hope to hear from you all so I know if there is a real solution to my problem.





The two bathrooms only using normal instant water heater. Only 2 adults in the house.


Thanks!

Probably cheaper to just make a hole through the wall.

This option is only possible if the management allows to do so. No consent so far.

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This post has been edited by Kieff: Oct 8 2020, 11:56 AM

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This post has been edited by Kieff: Oct 17 2020, 08:47 PM

Hi
A new 3 stories house, 6 bathroom, solar heater system, will change to 12” rain shower in 3 master bathroom

Anyone can recommend which grundfos model suitable for me

Thank in advance

Hi guys, New double storey house here. Water pressure very low at upstairs bathrooms. Currently all 3 bathrooms (1 with rain shower) connected directly to water tank only. Was advised by contractor to do bypass first before adding pump. But im thinking to straight get a water pump + bypass. Any suggestions on pump models and installations procedure? Welcome to pm me if any plumber or pump seller.

Guys, this is the installation diagram proposed by my plumber for bypass + new pump installation. The pump will be CM3-5 PM1 supporting 3 bathrooms (1 with rainshower). It's a new house so will take the risk of the higher pressure pump. Is this setup ok?


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i suggest choose either bypass / pump only.. i m using pump from water tank to all washroom.

the risk that you need to think off:
1) bypass - if your area is having high pressure when is least occupied then you might have problem with all ur pipes.. when ppl balik kampung the inlet will have high pressure pressing all the pipes.. if u didnt do bypass the pressure is building on the inlet to water tank and maybe to your kitchen only.. but if you do bypass d the inlet pressure is going to all the water pipe and the leak joint might break

2) having pump will also test ur bathroom piping.. the pressure water may cause leakage especially if ur house is old

i have no regrets over having a pump at my house and i install it when i just got my house key with the understanding where i wont get warranty if there's a leakage due to pump.. i m having the problem also with my 1st floor water pressure.. its like pee...

I for one would isolate the ground floor pipe circuit from the pump meaning upper floor bathroom are pump driven only. The lower floor should be able to live without it unless:
1. Centralised hot water storage tank for all 3 bathrooms
2. old pipes with blockages restricting normal flow downstairs.
The pressure issue is clearly with upper floor. I had bad experience with occasional leaky toilet flush valves that empty my tangki. Problem lessened but still occur if I had continue living in my old DSH unless using high quality flush valves on downstairs toilet. Human habit in not switching off main switch on the water pump at times coupled with leaky flush valves can harm the pump.

You might want to check this post out. The poster should be able to elaborate. Put into context from his technique, if bypassing, it's only meant for ground floor pipes to kitchen and laundry only.
Summary, isolate with two outlets from tangki:
1. Pump driven for upper floor only unless exception mentioned.
2. Lower floor kitchen and laundry can consider bypass like shown in linked post plus its design input further discussed here.

This post has been edited by halcyon27: Dec 15 2020, 07:00 PM

Hi Guys,

Just got my water pump installed. Have decided to go with CM3-5 PM1 and add on Pressure Tank from my previously kaput Grundfos. 2 Bypass was made. 1 Bypass from water tank and 1 Bypass from main water inlet. So if Pump malfunction in future will still have water with decent pressure. Pump was supplied only by single source : water tank. Any comments would be highly appreciated. Thanks!


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Anyone knows if i can tap the water pump power to either the water heater/ aircond / lights outlet? Its because my water pump wiring nearest exit is near one of the bedroom.

i think u can do it with water heater or aircon outlet but not light outlet.

More or less ok. Though I like to install a checkvalve at the tank outlet before the mains connection to prevent mains going into tank via tank outlet and overflow the tank.


Hmm. Never mind. I think I see a checkvalve after the quarter turn ball valve

This post has been edited by slimey: Dec 17 2020, 12:45 PM

I'm still toying on between CM3-4PM1 and CM3-3PT.

From my survey, both comes with the same pump and motor, only difference is additional pressure tank, right?

And I understand that the pressure tank will help to stabilise the water pressure a bit and reduce the pump start/stop, thus might be good for the pump's lifespan.

But the pressure tank requires maintenance, and from here some is saying that ppl will charge RM300 just for this. Else some said it's easy to DIY, just need to pump in the pressure using a bicycle pump.

So my question is:

1) Is the pressure tank really helpful to the pump? Or it's just marginal and can omit it for the maintenance free operation?

2) If the pressure tank is really beneficial, I have no problem to just pump in the air once a year by climbing up to the water tank area. But other than pumping air, any other maintenance required by the pressure tank?

Thanks in advance for your answers / comments.

CM3-4PM1 = 40M HEAD = +- 4 BAR PRESSURE
CM3-3PT = 30M HEAD = +- 3 BAR PRESSURE

And I understand that the pressure tank will help to stabilise the water pressure a bit and reduce the pump start/stop, thus might be good for the pump's lifespan.
Only good if u have minor leaks at home, if new house with new pipes no need get PT.

But the pressure tank requires maintenance, and from here some is saying that ppl will charge RM300 just for this. Else some said it's easy to DIY, just need to pump in the pressure using a bicycle pump. As long as u can climb up, u can self do

PT no dry run protection wo, if no water it will run non stop, so PM better

This post has been edited by zheilwane: Dec 20 2020, 06:22 PM

UNI E CM 5-5pm1(1.6hp) grundfos do not have higher spec except uni e cm10-2 but high flow, low pressure

so better flowrate and yet good pressure teral AB 40 x 325 HS (2hp)

do ask plumber use 3/4" pipe instead of 1/2" for better flow since u gonna use 12" rain shower

Thanks for the info. Will look into this

hi anyone using Grundfos CM3-4PM1 or any CM series? hows the noise?