My main question is whether I need a separate pump in addition to the pump within the condensing boiler.
I am replacing a boiler. The previous boiler was the old open flue type and had two external pumps. The new boiler is a Vaillant EcoTec 630 plus system boiler. The boiler together with the hot water tank are situated in the garage. The boiler also feeds the hot water system to heat up three towel rails (i.e. they are heated whenever the hot water is switched on). There is an independent pump for the showers, which has a separate run to the house and back. The condensate from the boiler will be put into a soakaway adjacent to the garage wall. The pipe run from the beginning of the house and the boiler in the garage is approx 9 metres. The house has 4 bedrooms.
Almost all the engineers suggested that we needed a pump in addition to the pump included in the boiler and the shower pump. My chosen supplier does not believe that a separate pump is required. He states that the boiler pump will be sufficient to pump both the hot water and the central heating system to the house (quite apart from the shower pump which is independent). I am confused. What is the purpose of the additional pump? Is it required for the above system? What part of the system would it pump (i.e. central heating radiators, hot water etc). What difference would I notice if I do not have the additional pump installed?
Urgent advice would be much appreciated. Many thanks.