Grundfos CM-PS CMB3-37

Not a straight forward pump solution – Bought a Grundfos CM-PS CMB3-37 and a 200ltr pressure tank, about 7 months back and found the following; 1. the first 200 ltr tank that arrived was broken on the plastic base. It was so weak, it could not be stood on its base, when slid out of the box. I rang my mate, who is a 4 year year Mech Eng. Who berated me for buying chinese gear, when he… Read more

saw it. When the replacement one arrived, we very carefully slid it out of the box and did not let it touch the ground, then picked it up and slowly put it down, in the vertical position. Its a 2 man job, don't try this on your own. 2. The flexible hose that connects the base of the tank to the pump head is too short. You have no options on movement, when you get it connected. Needs to be a bare minimum of 200mm longer. If you use the inline filter, the pump has to sit 100mm or so higher, off the ground, so the hose is too short. 3. The Grundfos filter unit leaked like a sieve. I tried turning the o-ring upside down, stretching it a little, but no joy. I ended up putting 10 winds of teflon tape around it, and that fixed it. 4. The air bleed valve on the inlet side of the pump had a slow dripping leak from day one. Needed teflon tape to seal properly. It was hard to trace where it was coming from. I thought it might have been one of the pipe joints. 5. The pressure dial arrived with a crack running from top to bottom on the dial, but the box had no signs of impact or scratches. [See picture] I wondered if it had been a sale return to the Grundfos warehouse in NSW? Who knows. 6. I tried making the adjustments, as per the instructions, for the cut in and cut out pressures, but there was no perceptable change in output pressure. because the pressure is average, the washing machine needs to have water added by hand with a bucket, otherwise it dosen't get enough water, in time, when it starts its cycle.

So in Summary, i think you need to spend more. This one struggles, on a 3 bedroom house. In hindsight, I would have sized it larger, if i would have known the outcome from a practical level. I would have liked to be describing a better experience, but for me that was not the case.