I have just bought a large victorian property in need of total renovation. Part of the work will involve total replacement of all plumbing, including installation of an entirely new HW / CH system. So far I have had different advice from each of the three heating engineers who have visited!
The property is a 5 bed 3 bath / shower detached house in which four adults will be living. We need to heat the whole property comfortably and in addition provide sufficient hot water for at least 4 showers in quick succession (the morning rush hour)
Initially I thought a traditional vented system with a large cylinder would be the best bet however a mega flow has been suggested. I can see the argument for one, however with a 15mm supply pipe I am concerned that flow will be inadequate for running two outlets at the same time, hence my preference for a tank in the loft (a big one!) I understand that the toilets can also fill from the same loft storage tank to avoid pressure loss in the DHW when they are flushed - is this true? We have plenty of loft space to accommodate tanks etc. Also if my incoming water flow is not great won't my baths take ages to fill with a megaflow? I don't want to mess about with pressure boosting pumps etc.
To further complicate matters we are considering installing a woodburning boiler stove. While this will not be the primary heat source we would like it to feed in to the DHW / CH when it is in use, as we have access to free logs. I want to be able to run both the DHW and CH on just the woodburner should I wish too, although I realise its output will not be enough to heat the whole house properly, it should just take the edge off. The stove output will be around 12kw to water. Is it possible to operate the CH pump independently of the CH boiler to circulate this heat? In early autumn I may light the stove but not want to operate the CH proper, but without the pump on it may boil, and with the pump on won't the boiler kick in? Would a mega flow be able to accommodate two heat sources?
I have also considered a thermal store which seem ideal for feeding the woodburner into. However If I am operating only on the woodburner, switch on the central heating pump and deplete the stored hot water I presume I will have no DHW either - the woodburner would never catch up. Is it possible to set the CH pump to only come on when there is sufficient stored hot water, and to operate for just enough time to leave me some hot water? Also I don't understand how a thermal store which operates at 90+ degrees is able to return water to a condensing boiler at a low enough temperature to enable it to operate at its most efficient. I am concerned that with 3000 sq ft to heat, solid walls and original single glazed sash windows that my heating bills are going to be high enough already.
Any advice greatly appreciated!
The property is a 5 bed 3 bath / shower detached house in which four adults will be living. We need to heat the whole property comfortably and in addition provide sufficient hot water for at least 4 showers in quick succession (the morning rush hour)
Initially I thought a traditional vented system with a large cylinder would be the best bet however a mega flow has been suggested. I can see the argument for one, however with a 15mm supply pipe I am concerned that flow will be inadequate for running two outlets at the same time, hence my preference for a tank in the loft (a big one!) I understand that the toilets can also fill from the same loft storage tank to avoid pressure loss in the DHW when they are flushed - is this true? We have plenty of loft space to accommodate tanks etc. Also if my incoming water flow is not great won't my baths take ages to fill with a megaflow? I don't want to mess about with pressure boosting pumps etc.
To further complicate matters we are considering installing a woodburning boiler stove. While this will not be the primary heat source we would like it to feed in to the DHW / CH when it is in use, as we have access to free logs. I want to be able to run both the DHW and CH on just the woodburner should I wish too, although I realise its output will not be enough to heat the whole house properly, it should just take the edge off. The stove output will be around 12kw to water. Is it possible to operate the CH pump independently of the CH boiler to circulate this heat? In early autumn I may light the stove but not want to operate the CH proper, but without the pump on it may boil, and with the pump on won't the boiler kick in? Would a mega flow be able to accommodate two heat sources?
I have also considered a thermal store which seem ideal for feeding the woodburner into. However If I am operating only on the woodburner, switch on the central heating pump and deplete the stored hot water I presume I will have no DHW either - the woodburner would never catch up. Is it possible to set the CH pump to only come on when there is sufficient stored hot water, and to operate for just enough time to leave me some hot water? Also I don't understand how a thermal store which operates at 90+ degrees is able to return water to a condensing boiler at a low enough temperature to enable it to operate at its most efficient. I am concerned that with 3000 sq ft to heat, solid walls and original single glazed sash windows that my heating bills are going to be high enough already.
Any advice greatly appreciated!