V
VentOrUnvent
This is quite a long post... the gist of it is "is upgrading to unvented worth the extra cost compared to a straight boiler+pump vented upgrade?". There's a couple of other questions thrown in but that's the main thrust. Now some details...
We have a 5 bedroom, 3 bathroom house with good mains pressure (5.5 bar) and good differential pressure (3 bar) - I hope that's the right term to use - i.e. the pressure sustained when the kitchen tap is turned on. Our flow rate is also good at ~22 litres/minute.
Our current system is vented, boiler in the garage, ~120l cylinder in the hallway cupboard. The boiler is old and at 50 BTU is far too small for the house, which was extended a few years back without any upgrade to the heating system. We have all sorts of problems at the moment with rads taking ~90 minutes to start to get lukewarm and want that fixed so we can have a nice warm house quickly. Hot water recovery time is very good - 20 or 30 minutes to have enough hot water for a bath.
We also want to take advantage of technology like the Honeywell EvoHome to selectively and remotely control each room's heating.
We've had 5 heating engineers all recommend upgrading to an unvented system and moving the cylinder to the garage alongside the boiler. This has resulted in quotes of £7k+ (with the Evohome extra on top), with boiler suggestion around 27kwh (based on 14 radiators), cylinder size suggestions from 170-300l.
One heating engineer has suggested redoing the house's pipework into "upstairs" and "downstairs" instead of installing evohome. We've also been told by one person that we absolutely have to rip out all the microbore (and all the disruption that entails). We've also been told be one person that we definitely need an accumulator, the others have said not.
Adding into the cost factor we also have 2 Mira digital pumped showers to that's another £500 replacing those for the unpumped controllers.
We're struggling to know what the "right thing" to do is.
I guess our questions are:
- Is the unvented system really worth the extra cost of installation compared to upgrading the vented system? I understand unvented is "better", but is it £4k better?
- Should we replace microbore day 1, or is that something we should only do later after the system is cleaned and upgraded if we still have problems?
- Is the upstairs/downstairs pipework zoning worth the cost and effort when compared to putting in EvoHome?
- What size cylinder do we really need? We've had such a range of answers we just don't know how to estimate it.
- Do we need an accumulator with that pressure + flow rate?
Apologies for the long post but I appreciate any help you can give.
We have a 5 bedroom, 3 bathroom house with good mains pressure (5.5 bar) and good differential pressure (3 bar) - I hope that's the right term to use - i.e. the pressure sustained when the kitchen tap is turned on. Our flow rate is also good at ~22 litres/minute.
Our current system is vented, boiler in the garage, ~120l cylinder in the hallway cupboard. The boiler is old and at 50 BTU is far too small for the house, which was extended a few years back without any upgrade to the heating system. We have all sorts of problems at the moment with rads taking ~90 minutes to start to get lukewarm and want that fixed so we can have a nice warm house quickly. Hot water recovery time is very good - 20 or 30 minutes to have enough hot water for a bath.
We also want to take advantage of technology like the Honeywell EvoHome to selectively and remotely control each room's heating.
We've had 5 heating engineers all recommend upgrading to an unvented system and moving the cylinder to the garage alongside the boiler. This has resulted in quotes of £7k+ (with the Evohome extra on top), with boiler suggestion around 27kwh (based on 14 radiators), cylinder size suggestions from 170-300l.
One heating engineer has suggested redoing the house's pipework into "upstairs" and "downstairs" instead of installing evohome. We've also been told by one person that we absolutely have to rip out all the microbore (and all the disruption that entails). We've also been told be one person that we definitely need an accumulator, the others have said not.
Adding into the cost factor we also have 2 Mira digital pumped showers to that's another £500 replacing those for the unpumped controllers.
We're struggling to know what the "right thing" to do is.
I guess our questions are:
- Is the unvented system really worth the extra cost of installation compared to upgrading the vented system? I understand unvented is "better", but is it £4k better?
- Should we replace microbore day 1, or is that something we should only do later after the system is cleaned and upgraded if we still have problems?
- Is the upstairs/downstairs pipework zoning worth the cost and effort when compared to putting in EvoHome?
- What size cylinder do we really need? We've had such a range of answers we just don't know how to estimate it.
- Do we need an accumulator with that pressure + flow rate?
Apologies for the long post but I appreciate any help you can give.
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