DHW retro fit kits to convert System Boiler to Combi Boiler

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Does anybody know of a retro fit kit to convert a standard sytem boiler to a Combi boiler via an external flat plate heat exchanger/ flow switch? Short on space in property so need clever solution.
Cheers
 
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unless its a new boiler, simplest thing to do is actually buy a combi.

A Combi will have everything built in to serve this function,
plus the plate heat exchanger will be sized accordingly.

flow sensor (tap open), aqua sensor (water in the H/E),
Temp sensor + setting (limit boiler power) and probably some other sensors and parts i'm don't know of.


i once thought of trying to DIY it as a solution to shower pressure,
discounted it when i realised how many bits would be needed as a flow sensor would only say if i was calling for water, not what temp etc..

there are some plate heat exchanger kit's for "Thermal stores" if you are dead set on trying it yourself, they tend to include a circulating pump (not needed if fed off the boilers pumped flow) and a flow switch,
think you'd also need a wet/dipped thermostat on the outgoing flow to cut boiler power when you reach your threshold temp.

other than that i'd hate to guess!
 
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unless its a new boiler, simplest thing to do is actually buy a combi.

A Combi will have everything built in to serve this function,
plus the plate heat exchanger will be sized accordingly.

flow sensor (tap open), aqua sensor (water in the H/E),
Temp sensor + setting (limit boiler power) and probably some other sensors and parts i'm don't know of.


i once thought of trying to DIY it as a solution to shower pressure,
discounted it when i realised how many bits would be needed as a flow sensor would only say if i was calling for water, not what temp etc..

there are some plate heat exchanger kit's for "Thermal stores" if you are dead set on trying it yourself, they tend to include a circulating pump (not needed if fed off the boilers pumped flow) and a flow switch,
think you'd also need a wet/dipped thermostat on the outgoing flow to cut boiler power when you reach your threshold temp.

other than that i'd hate to guess!
I would of course add a blending valve to output control, don't want 80 degrees at the tap! Lol
 
it can be done but a few problems you will encounter..
1) the delay in time from opening a tap and receiving hot water
2) no control over the hot water temp (blending valve required)
3) uncontrolled heat in the plate heat exchanger will lead to accelerated scaling. In hard water areas you could end up needing to descale/replace the plate every 6 months or sooner.
4) 24kw is not alot, a purpose made 24kw combi will supply around 9-10 l/min of water raised 35C. I would factor in some additional loses just in case so expect say 8 l/min or so.
 
and its on a pellet boiler

You would probably need it set up similar to an oil boiler with on board storage.
Check with the manufacturer though they will likely say no.
Many recommend large buffers for minimum burn times.
 
and its on a pellet boiler

You would probably need it set up similar to an oil boiler with on board storage.
Check with the manufacturer though they will likely say no.
Many recommend large buffers for minimum burn times.

yeah its true a buffer would be much better, as there would be a considerable boiler time lag from cold with no CH already in use.
 
Does anybody know of a retro fit kit to convert a standard sytem boiler to a Combi boiler via an external flat plate heat exchanger/ flow switch? Short on space in property so need clever solution.
Cheers

Think you might find it's illegal to modify any gas appliance beyond what it was designed for.
 
Does anybody know of a retro fit kit to convert a standard sytem boiler to a Combi boiler via an external flat plate heat exchanger/ flow switch? Short on space in property so need clever solution.
Cheers

Think you might find it's illegal to modify any gas appliance beyond what it was designed for.
 
Does anybody know of a retro fit kit to convert a standard sytem boiler to a Combi boiler via an external flat plate heat exchanger/ flow switch? Short on space in property so need clever solution.
Cheers

Think you might find it's illegal to modify any gas appliance beyond what it was designed for.

Thank for that info, but if you read my post you would see its not a gas appliance! :confused: Did you fail to get in the police force before heating?
 
Does anybody know of a retro fit kit to convert a standard sytem boiler to a Combi boiler via an external flat plate heat exchanger/ flow switch? Short on space in property so need clever solution.
Cheers

Think you might find it's illegal to modify any gas appliance beyond what it was designed for.

Thank for that info, but if you read my post you would see its not a gas appliance! :confused: Did you fail to get in the police force before heating?

Well mick (or is it prick?), as you mentioned system boilers and combi boilers AND this being a central heating site, one would assume thats what you meant. So keep your pathetic insults to yourself along with your absolutely childish questions. If you show civility you just may get it back. Go to nomates.com if you want to apply that attitude
 

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