Boilermate 2000 - Hot Water Supply Pressure Low

Hi,

Sorry if this is a silly question!

Does the pump connected to the heat-exchanger affect the pressure of the hot water supply to taps/showers, or is that just to pump the hot store water through the exchanger to heat the mains water supply.

My hot water has correct temp, but pressure becomes very low when more than one hot tap/shower is on. From the info in manuals and on this site, I suspect that can only be because of scaling in the exchanger, rather than the rightmost pump operation, which is running freely(I checked) though the local call-out company suggests it is running too slowly - but if it is not connected to the hot water supply, why would that matter - does that pump need to run very quickly for the job it's doing? Anyway, apparently I need a new pump AND a new exchanger (around £645 inc VAT).

I just wanted a quick second opinion and clarify my understanding before I ask them the same silly question, and also before I part with such a huge amount.

Cheers,
Bernie

Hi Bernie,

The HW flow rate will be affected by water scale in the HE so a new HE is indicated. Your thinking is correct though, the pump will NOT be affecting flow rates as it pumps stored hot water throught the HE to deliver the heat energy to heat the cold tap water on its way to the hot taps. Pumps rarely need replacing on the BM2000 so I'd say just order the HE for now. The part should cost about £100 or so and takes about an hour or so to fit, including partial drain-down then refilling. Any longer than that tells you the technician doesn't really know what he is doing ;-)

Typical price for a new HE should be around half the figure you quoted in my view, depending on how far the technician has to travel.

Cheers, Mike