Linking Two Unvented Cylinders

[Dragoon]

Theres nothing temperamental, special or complicated with a thermal store. Without having multiple inputs though it will cost you an arm and a leg maintaining sufficient temperature in the thermal store for your requirements.

I did my research on thermal stores a couple of years ago, but I remember vaguely something about issues with the mixing with cold water after the hot water's come through from the heat exchanger. Also heat exchanger problems as well, but the ol' memory's not too good so couldn't say for certain. But I do remember being impressed by them!

 

[Best]

Stainless Steel unvented cylinder = hot water up to as much as 65 degrees at usually 3bar pressure & full flow of your pipe work. Nothing really competes with that - & a powerful whole house pump costs a lot & is mechanical, so it won't last forever & it makes a noise.

 

[SimonG]

I did my research on thermal stores a couple of years ago, but I remember vaguely something about issues with the mixing with cold water after the hot water's come through from the heat exchanger. Also heat exchanger problems as well, but the ol' memory's not too good so couldn't say for certain. But I do remember being impressed by them!

Horses for courses, but I dont think this is your horse

 

[Dragoon]

Stainless Steel unvented cylinder = hot water up to as much as 65 degrees at usually 3bar pressure & full flow of your pipe work. Nothing really competes with that - & a powerful whole house pump costs a lot & is mechanical, so it won't last forever & it makes a noise.

Hi Best.

Yeah thats what the original idea, and I think I'm slowly coming back to that again. It's tried and tested! And it works! And all plumbers are familiar with it! And it's hot enough not to be dampened by a cold shoulder! :yes:

 

[Micksta]

Im Probably to late but have you thought about a Worcester Bosch high flow 440, works on the same principle as a Combi but slightly different.

 

[Dragoon]

Hi Micksta.

Sorry for the late reply. Just got very busy with other things recently.

I’ve had a look at the Hightflow 440, but it looks like another combi to me. How is it slightly different?

I’ve kind of discounted combis now, and am looking just for regular unvented cylinder with system boiler.

I asked a couple of cylinder companies about linking two cylinders (to save on fuel consumption), and it certainly can be done (according to them). However after considering it at some length, I’ve abandoned the idea because:

My main worry is that if the thing ever goes wrong, I just want to be able to call up the first available plumber to fix it. However if the installation is a little complicated, that may be a problem.

Also I’d have to sort some way to combat the legionnaires problem for the cylinder that’s not used as much.

So just gonna go with a standard unvented cylinder with a system boiler. And since I’d be just topping up the heat inside a well insulated cylinder the running costs shouldn’t be too nightmareish!! . . . . . . hopefully!

 

[drip-dry]

Hi Micksta.

Sorry for the late reply. Just got very busy with other things recently.

I’ve had a look at the Hightflow 440, but it looks like another combi to me. How is it slightly different?

I’ve kind of discounted combis now, and am looking just for regular unvented cylinder with system boiler.

I asked a couple of cylinder companies about linking two cylinders (to save on fuel consumption), and it certainly can be done (according to them). However after considering it at some length, I’ve abandoned the idea because:

My main worry is that if the thing ever goes wrong, I just want to be able to call up the first available plumber to fix it. However if the installation is a little complicated, that may be a problem.

Also I’d have to sort some way to combat the legionnaires problem for the cylinder that’s not used as much.

So just gonna go with a standard unvented cylinder with a system boiler. And since I’d be just topping up the heat inside a well insulated cylinder the running costs shouldn’t be too nightmareish!! . . . . . . hopefully!

Well if.you have room for the storage tanks ...most plumbers would say you have made the right chose..

 

[Micksta]

Well if.you have room for the storage tanks ...most plumbers would say you have made the right chose..

Correct if I had the choice I would go mains fed cylinder every time, good pressure, quick heat recovery, cheap to run, put in a hot water return this will cut down on the water siting still and cut down the legionnaire thing.

 

[Micksta]

Hi Micksta.

Sorry for the late reply. Just got very busy with other things recently.

I’ve had a look at the Hightflow 440, but it looks like another combi to me. How is it slightly different?

I’ve kind of discounted combis now, and am looking just for regular unvented cylinder with system boiler.

I asked a couple of cylinder companies about linking two cylinders (to save on fuel consumption), and it certainly can be done (according to them). However after considering it at some length, I’ve abandoned the idea because:

My main worry is that if the thing ever goes wrong, I just want to be able to call up the first available plumber to fix it. However if the installation is a little complicated, that may be a problem.

Also I’d have to sort some way to combat the legionnaires problem for the cylinder that’s not used as much.

So just gonna go with a standard unvented cylinder with a system boiler. And since I’d be just topping up the heat inside a well insulated cylinder the running costs shouldn’t be too nightmareish!! . . . . . . hopefully!

Correct if I had the choice I would go mains fed cylinder every time, good pressure, quick heat recovery, cheap to run, put in a hot water return this will cut down on the water siting still and cut down the legionnaire thing.

 

[Gray0689]

Secondary return only if very long pipe runs

 

[Ch4 plumbing]

Secondary return only if very long pipe runs

And on a timer and lagged.

 

[Gray0689]

And on a timer and lagged.

And sized correctly but only really cost effective in a large house

 

[Micksta]

And sized correctly but only really cost effective in a large house

Correct, but still worth while.

 

[Worcester]

For cylinders, consider the Joule Eco - extra insulation, water kept warm and cosy, even less heat loss.
Insulate all pipes - the 'boiler room' shouldn't be warm that's just bad installation/ insulation.
On our installs we are having to install small rads in airing cupboards for people as our buffers, thermal stores, DHW cylinders and pipework is so well insulated. - We even insulate the primaries from the heat source to the DHW cylinder, as well as the DHW distribution pipes - remember any DHW secondary returns should also be insulated.

Insulation will ALWAYS pay you back on running costs.