Secondary DHW loop on a combi?

[stonehouse]

Dan,

Well, I thought you had to buy a 'sealed' boiler if you wanted an unvented cylinder. I didn’t realise that an OV boiler with an F & E tank could be used. OK maybe not ‘intermediate’ but I can’t think of a good word.

 

[Terry lambert]

An unvented cylinder is mains hot/cold water but you can keep the heating/boiler open vent

Edited for spelling

 

[Phill Peck]

Why anyone would have an open vented system is beyond me.
Only reason would be very old pipework but if full renovation is on going that shouldn’t be a problem
@stonehouse any reason you want OV?

 

[dilalio]

Why anyone would have an open vented system is beyond me.
Only reason would be very old pipework but if full renovation is on going that shouldn’t be a problem
@stonehouse any reason you want OV?

Indeed. Only reason’s I can think of is risk of pressurising old pipes, as you say, and needing discharge provision - but that’s required anyway for the DHW.

 

[Terry lambert]

@dilalio

Not if the hot water is unvented

 

[Hot&Cold]

My house (recent purchase) is currently undergoing a major refurbishment.

Well,its the ideal time to have a decent hot water heating system installed.
In the drawing #5 shows the shower located at one side of the property and the boiler the other (no dimensions included) but i assume you want the shower to issue a powerfull flow rate at all times.There are many types of shower systems,some have standard flow rates and others have multiple outlets and need much more available flow. which type of shower are you interested in ?

Shower mixer equipment needs consideration,Quality varies so dont rely on glossy internet adverts. Buying well known brands with documented flow rates is a good idea.

The new system will be bespoke and needs detailed onsite consideration,the answer is not on the internet.

The only thing I don't like about combi's is latency.

That could be the least of your problems.

 

[dilalio]

@dilalio

Not if the hot water is unvented

Eh?

 

[Terry lambert]

Eh?

Miss read it

 

[Terry lambert]

Thought at first glance you were talking about the vent on hot water

 

[dilalio]

Thought at first glance you were talking about the vent on hot water

Lol! You had me rereading what I’d posted - got a stinking cold and my brain is mucking fuddled at the moment