Combi Comparison - any real life experiences?

[Gasmk1]

Nothing new in multipoint boiler combo we did that in uk during the 60’s and 70’s, before comb is invented, but using both now would be 2 or 3 flues increased gas pipework and possibly increase to u 16 meter

 

[gmartine]

Mods, is there any relationship between this Rinnai fan boy and that other member (or two) that espouses their use?

There is some familiarity in their sheer arrogance as well as bloody mindedness and I assume that multis are not allowed.

 

[SJB060685]

Mods, is there any relationship between this Rinnai fan boy and that other member (or two) that espouses their use. There is some familiarity in their sheer arrogance and bloody mindedness and I assume that multis are not allowed.

Something doesn't add up does it.

 

[gmartine]

There's certainly a familiar ring of supreme being about this poster but why he needs to hang around this uneducated pleb hole for confirmation I do not know.

 

[hometech]

No it’s a stupid idea

Can I take up a challenge for charity with you! You provide proof to the group (pictures of installations you have made and testimony from the customers who subsequently had them removed). For every proof you provide of the install/remove cycle, together with verifiable testimoney, I will pay £1000 to a charity of your choice. I will have to set a limit of £10,000 (so maximum 10 customers). I will have a chat with some people from my former chambers who will validate the details and handle the legals....Over to you

 

[hometech]

Informed and educated ?

I've installed hundreds of continuous flow units.
They do have their limits and their rated performance is on a 25C temperature rise.
They do perform substantially better than combi units but their downfall is on gas consumption.
Eg: Rinnai 26 ( 26 ltr's per minute at 25C temperature rise ) require 200mJ/h of gas.
They may not need that amount all the time but that's what's on the compliance plate, so the gas line has to be sized to that units plate requirement.

If they are installed without the adequate gas supply, they are not very good at supplying hot water.

Returning to you point about being educated and informed, there may be a lot more knowledge required on your behalf , before you start specifying these units on your clients property's.

If you can install the unit close to the main use taps and gas meter, then feasible.
If you have to run 30m of gas pipe to the units location, then you're up for some added costs.

so you know that you set the water temperature right... so you know that you only heat to the temperature you desire and not above that to then mix down. So 26l per minute would be a great water flow into any property...but the average is much lower..you know that too right! As for output in terms of heated water. The lowest recorded temperature for mains water was recorded in 2001 @ 4.9 degrees. So lets take the worst ever situation and raise that by 25 degrees. That would give a flow temp of 30 degrees @ 26l. The average shower temp is between 32-35 degrees. If the average home does not have 26l input. how can it achieve that as an output. Perhaps you are confusing measurement sizes with Australian. 30m gas pipe in an average UK home? Do you mean stately homes?

 

[SJB060685]

@hometech I'm just curious, what tickets do you hold relevant to the plumbing and heating industry? This is not me being rude, or trying to belittle you in anyway, I'm genuinely curious. A lot of the engineers on this forum have been doing this for decades, it's seems stupid to argue with their advice.

 

[oz-plumber]

so you know that you set the water temperature right... so you know that you only heat to the temperature you desire and not above that to then mix down. So 26l per minute would be a great water flow into any property...but the average is much lower..you know that too right! As for output in terms of heated water. The lowest recorded temperature for mains water was recorded in 2001 @ 4.9 degrees. So lets take the worst ever situation and raise that by 25 degrees. That would give a flow temp of 30 degrees @ 26l. The average shower temp is between 32-35 degrees. If the average home does not have 26l input. how can it achieve that as an output. Perhaps you are confusing measurement sizes with Australian. 30m gas pipe in an average UK home? Do you mean stately homes?

Perhaps all the bright ideas that you have alluded to your vast new found knowledge regarding plumbing, have been common knowledge for most plumbers for 20 odd years.

By the way, average shower temperature is 43C.
Why would you shower in water colder than your body temperature?

As for temperature setting devices, they are rarely installed anymore.
Who wants to set a temperature every time they open a tap.
If you have multiple pads in a house, you have to check them, because the unit will only heat to the lowest set temperature. You have to make sure the bathroom pad is switched off after use, because it over rides all other pads and the other pads cannot be altered if the bathroom pad is 'on'

Stately Homes?
I'm doing a 2 bedroom, 1 bathroom terrace at the moment.
Gas pipe length from gas meter Rinnai 26 - 25m in total ( index length )
On the way there is a 12 kW boiler and gas cooker.


That' enough information for you to work out the gas pipe size from the gas meter to the Rinnai 26.

Assumed, acquired, guesstimated knowledge will always be outdone by educated and practicable knowledge.

 

[hometech]

Perhaps all the bright ideas that you have alluded to your vast new found knowledge regarding plumbing, have been common knowledge for most plumbers for 20 odd years.

By the way, average shower temperature is 43C.
Why would you shower in water colder than your body temperature?

As for temperature setting devices, they are rarely installed anymore.
Who wants to set a temperature every time they open a tap.
If you have multiple pads in a house, you have to check them, because the unit will only heat to the lowest set temperature. You have to make sure the bathroom pad is switched off after use, because it over rides all other pads and the other pads cannot be altered if the bathroom pad is 'on'

Stately Homes?
I'm doing a 2 bedroom, 1 bathroom terrace at the moment.
Gas pipe length from gas meter Rinnai 26 - 25m in total ( index length )
On the way there is a 12 kW boiler and gas cooker.


That' enough information for you to work out the gas pipe size from the gas meter to the Rinnai 26.

Assumed, acquired, guesstimated knowledge will always be outdone by educated and practicable knowledge.

I never mentioned shower temp in my response so why obfuscate?
Maybe you can explain to the shareholders of the worlds largest manufacture (by volume) of wall hung heating devices that there is no market for their product (despite sales in the millions each year lol)
You set the temp as a default and then change it if required....but you know that right, you have installed hundreds of them?
And then you contradict yourself..
The average 2 bedroom property in the UK is 6m in length and 4m width (new build) 2.3m ceiling height. How on earth can you get 25m?
I'll call you....Double first, GDL, BPTC and 38 years of electronics and patent litigation experience...lets' see your hand?

 

[oz-plumber]

So lets take the worst ever situation and raise that by 25 degrees. That would give a flow temp of 30 degrees @ 26l. The average shower temp is between 32-35 degrees.

I never mentioned shower temp in my response so why obfuscate?

???????????????????.

You did mention shower temperatures

Who's Obfuscating?

( I did have to look that one up )

No hard feelings.
I just read what you wrote and replied to what you wrote.