advise on unvented cylinder with solar thermal

[bluegem1]

Hi just new to this forum so Hope somebody can help. I have a customer who has an old floor mounted conventional gas boiler. He is wanting to renew to a condensing system boiler with unvented cylinder. He is looking at the possibility of adding solar thermal at a later date so is wanting the cylinder with the extra coil for a later date.

I have not had any dealings with solar thermal as of yet and as much as I am not going to be installing it personally I would like to offer him a bit of advice on it. Also any recomendations on what cylinder? I normally fit Viessmann or baxi boilers and know that the viessmann cylinder get a good name but are a bit pricey.

Any advice on this would be greatly appreciated.

 

[chris watkins]

Just ask the manufacturers for what size they would recommend. It does need to be matched to the size of the house & the number of hot water fittings along with the number of panels to be installed. In other words not too big & not to small.

If they are not going to have the solar to a later date then would recommend that primaries are connected through the lower solar coil as well as the top one to ensure water is heated in lower section to avoid legionella.

 

[GasmanxxxR1]

You need 100 litres of water per panel or they cant get rid of the heat and cook. 200L is seen as the minimum needed.

To my mind most of the unvented cylinders are the same as they are all manufactured to a certain standard. I like range, oso or rm cylinders

 

[townfanjon]

Hi , i have a viessmann solar unvented , i think they are santons , which are ok cylinders, like rob says most if not all are manufactured to the required standard, the one big plus point with the viessmans is with the 4 pipe system boiler the HW is controlled by a sensor not needing a 2 port and all the wiring you would normally need.

 

[Ermintrude]

ACV SLME . Leave solar coil dry and clean