Unvented cylinder sizing

[Riley]

Have been asked by a customer to fit in unvented cylinder in a small guest annex. For two people maximum

Cylinder will serve bath shower basin and kitchen sink

Customer has highlighted to me however that the bath is colossal approximately 350 L of water

He also says that the likelihood is that the shower and bath will be in use at the same time

With this in mind I was leaning towards the 300 L cylinder would you guys agree ???

Just want to make sure I don't undersize this

 

[wattsie1987]

Have been asked by a customer to fit in unvented cylinder in a small guest annex. For two people maximum

Cylinder will serve bath shower basin and kitchen sink

Customer has highlighted to me however that the bath is colossal approximately 350 L of water

He also says that the likelihood is that the shower and bath will be in use at the same time

With this in mind I was leaning towards the 300 L cylinder would you guys agree ???

Just want to make sure I don't undersize this

As rough guide of 2 parts hot and one cold you could get a bath and shower at 10 lpm for 15 mins with a 300l cylinder. How will it be heated? With a decent recovery time you could probably get away with a smaller one but why take the risk.

 

[Riley]

It's gonna be direct

 

[quality]

600 then if it direct lol

 

[JCSPLUMBING]

300 will be fine with good mains flow rate and pressure. No one has a 60 degree bath so would only be half full with hot water.

 

[Nostrum]

Store it hotter and mix it down if possible. What's it gonna be to need a 350l bath and shower at the same time, a brothel or something?

 

[Riley]

It's an old farm and they are gradually changing all the old buildings to guest accommodation to a really high standard

 

[wattsie1987]

Is thermal store an option?

 

[Riley]

Wattsie cheers for the input. If I'm honest since college I've not worked on one. Very uncommon in this area. What would be the pro/con over unvented

 

[SimonG]

Direct thermal store, expensive to run.

I would be concerned further down the road if he his going to upgrade other units. That would be some loading on the electrics.

 

[Riley]

So I'm thinking stick with unvented then

 

[SimonG]

I would want multiple heat sources for a thermal store. Depends what the blokes long term plans are. Pellet boiler?

 

[wattsie1987]

I would want multiple heat sources for a thermal store. Depends what the blokes long term plans are. Pellet boiler?

That's what I was thinking if there is multiple dwellings. Log burner for heating with a thermal store can work well and economy 7 backup if there's an option for pv panels could work out really well.

 

[Riley]

Nope will be electric throughout. Only place with boiler is main farm house. Would you guys not opt for unvented then?