**boiler Question!**

[Lisa_Louise]

Any plumbers or boiler people who can help with this query please?!
What is the difference between a combi, system and open vent boilers ?

I am used to a combi boiler, instant hot water on demand, whenever I need it. I am moving to another property but it has an open vent boiler.... I have an idea what this is but cannot find more info... Like, does this mean I now have to wait for the hot water cylinder in the airing cupboard to heat the water up to have a shower, wash my hair or have a bath? Or is it like a combi where the hot water is instant and no waiting around for the water to heat up? Is there Anything else I should know that is different to a combi?

By the way, the boiler in the next place is a Vaillant ecoTEC plus 415 if that is any help!

Much appreciated

[bhg481]

The Builder - it's interesting how sizes change over the years. A few months ago my power-shower pump got noisy so I decided to change it before it gave up on me. I installed the shower many years ago with 18mm fittings; the replacement pump, same make and model, needed 15mm fittings.
I assume all these changes to smaller pipe sizes are attempts to reduce the costs but it must be trivial on the cost of a house.
I do understand your point about the feed to the hot-water cylinder; since all my bathroom taps etc were indirect when the house was built it wasn't a problem for me but I see the need to be careful if modifying a newer system.