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yes but as he said the reason they want two boilers is one for back up (so they still have heating and ho****er) incase one goes down so design the system right

so size up the system for one boiler and then add a back up boiler

so if one goes down the other one will be able to heat the system (totally)

and then you wont get a phone call in the middle of winter my heating isnt warm (when running off one)


And you can reply, 'that's because your boiler is broken'.

You'll get a better modulation range from two smaller boilers, which judging by the set up, the demand could vary considerably.

OP, I'd use a LLH.
 
And you can reply, 'that's because your boiler is broken'.

You'll get a better modulation range from two smaller boilers, which judging by the set up, the demand could vary considerably.

OP, I'd use a LLH.

yes but when the cus has asked for on boiler to be used incase one goes down + with general heating etc
 
Customer wants in built fail safe so if one fails then the other is still there working, and they also can turn one off in summer.


Customer sounds like he's using common sense, you sound you're just suggesting installing a boiler which will be sat doing :nono: all for 99.9% of its life.

I think it's safe to assume that if the boiler fails in deepest darkest winter, one will not do the job of both. It will still be able to do something.
 
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Customer sounds like he's using common sense, you sound you're just suggesting installing a boiler which will be sat doing :nono: all for 99.9% of its life.

I think it's safe to assume that if the boiler fails in deepest darkest winter, one will not do the job of both. It will still be able to do something.

do you think the cus will accept that stating that he wants a back up boiler and you saying he can only run 1-2 systems off it not the full heating/ hot water

thats why i said either do it right or get the cus to sign to say the back up boiler/ system is there for the essentials eg hot water or heating zones and not both

your call op but think either the cus will complain if not done right

and depending on system size i would use a llh or use bigger than 28mm f+r
 
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Yes, we have fitted several like this. The most recent being two floor standing worcester 40cdi classics. However the pipework involved in this system was much larger(2"+) and I wasnt worried about the boilers turning off prematurely.
 
Yes, we have fitted several like this. The most recent being two floor standing worcester 40cdi classics. However the pipework involved in this system was much larger(2"+) and I wasnt worried about the boilers turning off prematurely.

any reason you didnt go for a couple of worcsters 162?
 
The tank is 210l unvented and MI's say that it requires around 18kw... In order to achieve the stated 30min reheat time.

has anybody included a rad in the primary circuit before to increase its water capacity? or is it a stupid idea in my head lol
 
The tank is 210l unvented and MI's say that it requires around 18kw... In order to achieve the stated 30min reheat time.

has anybody included a rad in the primary circuit before to increase its water capacity? or is it a stupid idea in my head lol

log back in else a mod might close this 😉
 
Thanks, what faults are you referring to?
(this image was taken before I made a frame to support the flue)

Im told not bad for a 21 year old
 
i can understand the principle of some heat and hot water being a compromise its better than nothing when a single boiler fails and there is possibly an imersion in the cylinder
 

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