Strange fault

[rocketmanbkk]

Sounds like it. I got one also but the custard is fully aware it's not the best solution so I've covered my butt

 

[turnpin]

did you remove the old pump and if so did it have a small pressure vessel attached to it...regards Turnpin:smile5:

 

[Phil]

I bet the original pump supply pipework is the usual 15mm long and tortures restrictive bodge that was just about able to supply the old set up.

As said the new pump and bar mixer may be just that little bit more restrictive leading to a drop showerhead to start pump situation.

 

[gassafe]

Take the mini check valves outta the shower inlets...

 

[joni os]

I have been asked to advise on similar problem with monsoon pump. Fixed head won't work, shower head needs to be dangling on hose to start. Apart from minimal head CWS/Pump and avoidable elbows everything OK. Thought it one off but apparently not. Please update with solution.

 

[Best]

Negative head pump fitted and that should be it solved

 

[spanner]

Need a negative head pump. I've had the same before with a client and as the price of the n/h pump was almost twice the price they'd agreed to have the ordinary 1.5 bar twin imp pump installed, as the height of the cwsc was lower than the shower head.
Fitted a surrey flange, and independent cold water feed from cwsc. Works fine once the shower is lowered to bath tap level. Constant balanced hot and cold to the shower thermostatic mixer.
Hope this helped

 

[Unregistered]

The old pump didn't have a vessel attached.
The cws tank is higher than the shower head as its in the loft but perhaps it's not quite high enough.
ill see if I can remove non returns in shower and see if the water level in cws tank can be raised via ball valve.

 

[spanner]

That's the answer. Definitely not enough pressure to get the pump to kick. Obviously lowering the shower head to tap height increased flow allows pump to operate. Hope it goes well.