Joining the Renewable Heating Hub forums is completely free and only takes a minute. By registering you’ll be able to ask questions, join discussions, follow topics you’re interested in, bookmark useful threads and receive notifications when someone replies. Non-registered members also do not have access to our AI features. When choosing your username, please note that it cannot be changed later, so we recommend avoiding brand or product names. Before registering, please take a moment to read the Forum Rules & Terms of Use so we can keep the community helpful, respectful and informative for everyone. Thanks for joining!
Basic advice/opinions on complex heating system: Chromagen
Hello,
I recently bought a house in Italy with a fairly complex heating system.
(I don’t know much about heating systems, so it might not be complex to other people here).
I would value any comments you might want to make about the basic system (pic attached). Some things about it don’t seem right to me, although I have checked all the pipework thoroughly, so I’m confident the diagram is correct.
Thanks…
To be better able to assess your system it will be necessary for you to include pumps/valves etc. on the schematic.
I would expect the pipework from the gas boiler to the thermal store to be opposite to that shown.
What is the make and model of your thermal store?
The tank has a plate that says: "Chromagen, Model: BSF750V2M085". There's also lots of other information on the plate.
I've added the pumps and valves to the diagram.
I also wondered about the position of the pipes from the gas boiler, but I checked them several times and I'm sure that's the way they are.
The ground floor has UFH (there are two separate UFH loops - it's a big house and I didn't put all the details on the diagram). Each UFH circuit is controlled by a room thermostat controlling a valve in the return pipe from the loop. The feed pipe goes through a mixer valve, which I assume mixes the feed and return in order to achieve the correct temperature.
The first floor uses radiators. There are 8 radiators, divided into two circuits, each circuit is controlled by a room thermostat.
From the information provided this is how I assume your system is designed to work.
On sunnier days the solar thermal system heats the water in the thermal store, which I believe also acts as the hot water cylinder.
If the UFH systems operates, water is passed through a heating coil within the thermal store and absorbs thermal energy which is supplied to the UFH loops. As you have stated the water temperature may be reduced by the mixing valve.
Having given some thought on the subject, I believe that the pipework from the gas boiler is reversed from the normal arrangement for a reason. When solar energy has been collected within the heat store this can then be used in preference to burning gas. I am assuming that the water pump is within the gas boiler, so to get water to the radiators it is necessary for the gas boiler to operate, but by heating this water in a heating coil within the thermal store before it goes as return water to the gas boiler, the gas boiler may not need to fire or fires at a lower output.
In the Winter months when solar thermal energy may be limited, the gas boiler will not only supply the radiators, but also warm the thermal store and hence supply the UFH and DHW.
I think that the thermal store must therefore contain three individual heating coils, one for solar thermal, one for UFH and one associated with the gas boiler.
Thanks, Derek, that gives me a lot to think about. I'll try to absorb your analysis and get to grips with the system!
- 26 Forums
- 2,725 Topics
- 63.8 K Posts
- 1,068 Online
- 7,126 Members
Join Us!
Installer Finder
Degrees of Separation
Latest Posts
-
RE: Jokes and fun posts about heat pumps and renewables
@transparent I’ve heard that that is why American cars ...
By Toodles , 5 hours ago
-
RE: HeatGeek vs Octopus surveys: puzzling disparity - any ideas why?
Have either quote provided room by room heat loss calcu...
By Old_Scientist , 19 hours ago
-
RE: Heat Pump Servicing & Maintenance – Good Value or Rip-Off?
@old_scientist if you are going DIY then you may wan...
By Papahuhu , 2 days ago
-
RE: Indevolt Batteries UK Support & Info Thread
After a short while that was followed by the 'power war...
By JamesPa , 2 days ago
-
RE: Samsung heat pump - data cable issue
That's well done. Cable is the correct type (LIYCY = 2x...
By bobflux , 2 days ago
-
RE: Electricity price predictions
I agree, we will find out at the next budget whether th...
By Old_Scientist , 3 days ago
-
RE: Missing flow temperature in Heat Geek proposal
@editor I went through HG website, so should be ok for ...
By sttpd1917 , 3 days ago
-
Who did the Freedom Heat Pump cloud server and what did...
By Mars , 3 days ago
-
RE: Who's your electricity provider and what's your tariff?
Reading between the lines of what octopus are doing wit...
By JamesPa , 3 days ago
-
RE: Air to air bus grant installer anywhere
The through wall two hole ones have their place (listed...
By EtchedPixels , 3 days ago
-
I hope it goes ok, Hon can be hard to set up IF the sof...
By Graham Hendra , 3 days ago
-
@clockworks Hi, So there is a big difference between st...
By ASHP-BOBBA , 3 days ago
-
@editor wellvery comprehensive answer. I will get all i...
By Keithb , 3 days ago
-
RE: Advice on my Heat Pump Journey: Old Stone Built Detached Cottage
all good advice I will follow this up
By PaulC , 3 days ago
-
Heat of vaporization of water is 2.25 MJ/kg (0.625 kWh/...
By bobflux , 4 days ago





