Salamander pump, not working. Help no cold water in bathrooms!

B

BBird

Guest
Recently moved new flat, on second floor, 70s block with low water pressure (10 storey). 2 bathrooms (back to back). Warned by agent not to install taps with ceramic disks.

For second time in 2 months, pump not working and no cold water in bath or shower rooms, and limited or no hot water (WC and kitchen have cold water, kitchen has some hot)

ALTERATIONS BY BUILDER
Builder replaced bath with a shower. Vado exposed shower valve (CEL149 1/2inch 1.2 bar). Vado low pressure handset.

Replaced conventional kitchen mixer tap with a Blanco mixer tap (ceramic disc valves suitable low pressure). And to stop splashing a Miracle Tap spray at end of the spout.

The Salamander lump was leaking and noisy, so got a plumber to replace with a new one Salamander ESP75 (positive/negative feed 2.2 bar). Understand our system needs negative feed.

PROBLEMS
All worked fine for a couple of weeks then without warning one morning no cold water in bathrooms, trickle of hot water, and pump flashing green/red 2* (*DRY RUN PROTECTION only occurs in instances of chronic aeration or water starvation after (2) ON OFF ON OFF operation and a 60 second recovery period).
In kitchen cold water running well (not off pump), hot water not bad. Turned off pump.

Plumber who installed pump spent 2 hours looking for fault. Eventually said hot water coming back into cold pipes. Suggested was fault with shower mixer valve (which had loose knob). Vado agreed faulty, sent an engineer, and replaced right 'knob' fitting. SYSTEM ALL WORKED FINE THEN!!

One month on exactly the same has happened. Pump goes on for a couple of minutes, then warning lights switch to same green/red. But even when on water doesn't run in bathrooms (only trickle of hot). So turn off pump.

Have already paid thousands to builder for refurb., and not happy with some of his work. His plumber prepared the plumbing for shower, but builder fitted the shower. Another recommended plumber who is apparently familiar with our block has already had £800 or so to replace the pump, and research the subsequent fault.

I don't understand plumbing at all. Could this be a defect with the pump, one of the shower valves, the size of the shower head, the kitchen tap ceramic discs, or is it the pump??????.

Meanwhile having to carry buckets of cold water to bathroom for bath!