can someone please help? We have had a 210 litre unvented indirect cylinder installed we bought it but unfortunately we couldn’t use it as intended as we couldn’t get the required 20 litres per minute. So we are using it primarily as a vessel, we have had a tank in the loft fitted too and are due to fit a pump soon. However the tank is taking 4 and a half hours to fill. Is that right? Surely it should be quicker than that? Our plumber said it was because the tank is really big?