unvented cylinder

[Billy Bob Bob]

i need to spec a unvented cylinder on a job,currently has a duotec 40 he combi that i am going to use as a system boiler,trouble is i have not done unvented installs for ages so need advice sizing up the cylinder i need,needs to cope with 2 bathrooms ,will be using a megaflow

 

[SimonG]

180 litre or 210. What's the reason for the megaflo. Better options to give value for money.

 

[quality]

60ltr ish per person

 

[ShaunCorbs]

I would say it's down to the space you have and go for the biggest within reason

 

[Best]

I agree I would go at least one size up from whatever is supposed to be plenty, if space is enough.
2 bathrooms, but how many people?
Some of the literature on unvented units are handy for their guide on rough sizing

 

[GasmanxxxR1]

Megaflow are over priced, just fitted a Joule unvented - very nice indeed and cheaper than an RM cylinder!

 

[Billy Bob Bob]

looking at a 300l main

 

[townfanjon]

210 for that one , unless they bath with it 1" from overflowing .

I normaly use RM , but the last few have been centerbrand , I think they are cracking cylinders for the money

 

[iiplumbing]

Hi Guys
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[Ray Stafford]

What is in the two bathrooms Mark?

There is a big difference between a small tub or basic shower on the one hand, against a large Jacuzzi or a shower with drench head and body-jets on the other.

You could probably get away with 210 litres, but unless space is tight, the £cost difference between 210ltr and 250ltr or even 300 is probably trivial in the sum total of the job. With insulation so thick these days, and standing losses so trivial, I would support the general view of having as much stored volume as you can - at least up to 300 litres. Above that, you are getting into light commercial stuff anyway.

 

[mfgs]

There is no set size, it all depends on what is fitted and the flow rates they are capable of delivering weighed up against the likely demand for the household. If people generally bath or shower at different times then you can get away with a smaller cylinder with a quicker recovery time.

 

[Billy Bob Bob]

What is in the two bathrooms Mark?

There is a big difference between a small tub or basic shower on the one hand, against a large Jacuzzi or a shower with drench head and body-jets on the other.

You could probably get away with 210 litres, but unless space is tight, the £cost difference between 210ltr and 250ltr or even 300 is probably trivial in the sum total of the job. With insulation so thick these days, and standing losses so trivial, I would support the general view of having as much stored volume as you can - at least up to 300 litres. Above that, you are getting into light commercial stuff anyway.

1 bath and 3 showers ,do main come pre plumbed Ray?

 

[Ray Stafford]

1 bath and 3 showers ,do main come pre plumbed Ray?

Not to my knowledge Mark, although I wouldn't want to state it categorically.

We do the RM pre-plumb off the shelf.

If there is a realistic chance that all three showers will be used concurrently, and subject to the incoming main supporting 30+ lpm, I would be looking at a 300 litre cylinder.

 

[Billy Bob Bob]

Not to my knowledge Mark, although I wouldn't want to state it categorically.

We do the RM pre-plumb off the shelf.

If there is a realistic chance that all three showers will be used concurrently, and subject to the incoming main supporting 30+ lpm, I would be looking at a 300 litre cylinder.

That's my thinking on the 300 L,customer wants a megaflow,looking at the mains and santons as i can convince him they are the same cylinder but pre plumbed will save time ,tried to speak to my main rep but is on the sick,is Andy Burton your rep up with you? was my Rep down here a few years back

 

[GasmanxxxR1]

Is your customer aware its just a brand name?

I had a customer kept saying megaflow, bit like saying hoover instead of vacuum, convinced them in the end to get another make