I have an old fashioned vented system with two motorised valves. This is with a very old boiler (not condensing). I am confused about the set-up of hot water section.
The boiler flow is not forced through the hot water indirect tank coil - the flow can bypass it because the tank coil is connected across the same, continuous length of pipe after the pump, so there is an uninterrupted shunt across. I can't change this bypass since central heating has to flow through this pipe too, when on.
There is also an automatic bypass valve, but only after this assembly (not between the coil ends). If only hot water is running, all of the boiler flow is forced through this automatic valve - there is no other route. This only seems to make sense for the central heating to provide flow if the TRVs close - and this works correctly. But if hot water is on, the boiler flow is forced through it.
I understand that some bypass may be required since the boiler temperature return shouldn't get too cold - to stop condensation in the old cast iron boiler (not a condensing boiler). However, the boiler is cycling frequently and it takes a long time to heat the hot water cylinder.
Does this seem correct or should there be some boiler flow forced through the tank coil?
The boiler flow is not forced through the hot water indirect tank coil - the flow can bypass it because the tank coil is connected across the same, continuous length of pipe after the pump, so there is an uninterrupted shunt across. I can't change this bypass since central heating has to flow through this pipe too, when on.
There is also an automatic bypass valve, but only after this assembly (not between the coil ends). If only hot water is running, all of the boiler flow is forced through this automatic valve - there is no other route. This only seems to make sense for the central heating to provide flow if the TRVs close - and this works correctly. But if hot water is on, the boiler flow is forced through it.
I understand that some bypass may be required since the boiler temperature return shouldn't get too cold - to stop condensation in the old cast iron boiler (not a condensing boiler). However, the boiler is cycling frequently and it takes a long time to heat the hot water cylinder.
Does this seem correct or should there be some boiler flow forced through the tank coil?
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