Hi again
The next stage of the heatbank project will be the selection of a new boiler. However I'm having issues speccing up the system and so far my trusted plumber (CORGI installer for 10 years, will be fitting/comissioning the system and has his unvented ticket
) and my dad's cousin [whatever that makes him to me ] an ex 25year BG man now working for an independant (not on the install side though ) are a little unsure whether what I'm thinking is possible
Now I know that the mere fact that 2 experienced guys are unsure tells me that I'm probably thinking about this wrong but I'd welcome opinions from anyone else on my plan
I want to directly heat the existing copper cylinder. Since this circuit is completely seperate from the actual hot water I see no issue with this.
However, I assume that since my cylinder is just a stock copper gravity one I'll be unable to fit it into a pressurized primary system off the boiler. I don't know what a CU cylinder will take pressure wise and I certainly don't want to find out
So now I'm thinking open vent primary system. All OK so far.
Here comes the hard part
To keep the boiler running effeciently I'd like to fit a TMV in the boiler return. I'd connect this to the top and of the cylinder with the mixed port back to the boiler. I **should** then be able to set the return temp to the boiler to 50C giving me the 70C I want to run the store at on the flow, assuming a 20C deltaT across the boiler as well as giving me nice long efficient (from what I've read anyway) boiler burns
The problem I see is that the TMV is going to need some pressure to work. 0.1bar seems common. If I go my intended route of boiler and cylinder in the loft I'm going to struggle to get much more than 5ft of head for the system. I suspect it's going to pump over
Anyone make any sense of the plan and have any comments?
Cheers
Steve
The next stage of the heatbank project will be the selection of a new boiler. However I'm having issues speccing up the system and so far my trusted plumber (CORGI installer for 10 years, will be fitting/comissioning the system and has his unvented ticket
) and my dad's cousin [whatever that makes him to me ] an ex 25year BG man now working for an independant (not on the install side though ) are a little unsure whether what I'm thinking is possibleNow I know that the mere fact that 2 experienced guys are unsure tells me that I'm probably thinking about this wrong but I'd welcome opinions from anyone else on my plan
I want to directly heat the existing copper cylinder. Since this circuit is completely seperate from the actual hot water I see no issue with this.
However, I assume that since my cylinder is just a stock copper gravity one I'll be unable to fit it into a pressurized primary system off the boiler. I don't know what a CU cylinder will take pressure wise and I certainly don't want to find out
So now I'm thinking open vent primary system. All OK so far.
Here comes the hard part
To keep the boiler running effeciently I'd like to fit a TMV in the boiler return. I'd connect this to the top and of the cylinder with the mixed port back to the boiler. I **should** then be able to set the return temp to the boiler to 50C giving me the 70C I want to run the store at on the flow, assuming a 20C deltaT across the boiler as well as giving me nice long efficient (from what I've read anyway) boiler burns
The problem I see is that the TMV is going to need some pressure to work. 0.1bar seems common. If I go my intended route of boiler and cylinder in the loft I'm going to struggle to get much more than 5ft of head for the system. I suspect it's going to pump over
Anyone make any sense of the plan and have any comments?
Cheers
Steve
