Combi Boiler or Unvented Tank

[shotgunnufc]

Hi,

I was wondering if anyone could share some advice on what boiler system for us to go for.

We live in an old (1899) 5 bed house, there 3 floors but heating only extends the first floor currently. There are 8 radiators but when we extend into the 2nd floor we will add 2 more.

We have one shower but plan to add an en suite in the next few years.

The current system is a standard hot water tank and boiler (on its way out) with a cold water tank in the loft.

we had assumed that we would need an unvented cylinder and new boiler but then have been reading about the Worcester bosch combis. our main concern would be that the combi would not give us enough pressure to add the second shower and further radiators, but we would welcome the added efficiency and space.

what would your advice be?

thanks

 

[ShaunCorbs]

What's your incoming water mains pressure and flow rate ?

 

[shotgunnufc]

I've been reading other threads and saw this may be asked but if I'm honest I don't know, I plan to measure the flow rate this evening. how will I find out the mains pressure?

what would be your suggestion for either poor or low flow, high or low pressure until I find out?

 

[mfgs]

The Worcester highflow range can cope with 2 bathrooms and would easily do the heating side of things. If space isn't an issue a system boiler and unvented would be the better option.

 

[Riley]

As per what Shaun says as long as your flow and pressure are up to it and you've got the space I'd go unvented

 

[shotgunnufc]

just had a little look on the internet, will go to local plumbers merchants and get a water pressure guage so I'm a bit more clued up

 

[Riley]

I've been reading other threads and saw this may be asked but if I'm honest I don't know, I plan to measure the flow rate this evening. how will I find out the mains pressure?

what would be your suggestion for either poor or low flow, high or low pressure until I find out?

Id be tempted to get a couple of local engineers in to quote and then you can get them to test the flow/pressure armed with a little info. After all you need a G3 engineer to fit an unvented and a gas safe engineer to fit a boiler. It's really stuff they should be testing as a matter of course

 

[shotgunnufc]

we have had some engineers round. we were planning to go with a G3 registered engineer who suggested a velent unvented cylinder, it was only the most recent engineer who had suggested a combi, we'd never considered it until that point.

when he gets back in touch I will ask him about the flow and pressure. what is the minimum flow/pressure that we would need for a combi really?

 

[Howsie]

Try and get more than one estimate.

 

[Riley]

we have had some engineers round. we were planning to go with a G3 registered engineer who suggested a velent unvented cylinder, it was only the most recent engineer who had suggested a combi, we'd never considered it until that point.

when he gets back in touch I will ask him about the flow and pressure. what is the minimum flow/pressure that we would need for a combi really?

Many manufacturers will differ in their requirements. I know combis can do the job if it fits in with the households lifestyle but I think a guy recommending an unvented cylinder is offering you a more sensible solution particularly if you are looking at putting in a second bathroom

 

[Gasmk1]

The viessmann 111 is getting good reviews

 

[jtsplumbing]

If space is very limited take a look at storage combi's

 

[ShaunCorbs]

If space is very limited take a look at storage combi's

tbh there normally as big have a look at the viessmann 222