boiler choice

[sparra1100]

hi all have a bigish job coming up the house is having an extension it has 2 bath rooms 3 ensuites plus a cloakroom with a toilet and sink and a utilaty room 17 rads and may need a couple more bloke wants a combi i was thinkin of a worcester 440 highflow or a 550 highflow but could even go down the unvented root have even considered wether a 42 cdi would do it just looking into the optionas as the bloke recones he might use to bathrooms at a time anyone else come across this anyone any ideas or thoughts what they would do am swayed to the 440

 

[SimonJohns]

Don't go for the combi

Unvented would be my personal preference and then suitably sized boiler

 

[goz666]

Same here, unvented would be my choice too. I fit a vaillant 937 combi in a big house with 15 rads before christmas and hes happy with it. But theres now only two of them in the house and he assures me they have no plans to move and only one bathroom is needed at once. It was his choice, he's the customer, I gave him the options...he made the decision.

 

[mfgs]

A combi wont cope with the hot water demand with 2 bathrooms and 3 ensuites. If there are that many bathrooms I'm guessing theres a fair few people living there and all likely to want to use hot water at same sort of time in morning and evenings. Unvented would be best for this.

 

[grahamgas]

I would go unvented , but if he desperately wants a combi, then the vaillant 937, if he has a wall capable of taking it, or the big Qseries Atag 51 kw.
Or have a look at the rinnai twinflow. Basically a instantaneous water heater, coupled with an atag heat only boiler, but major benefit of these is that it can be fitted to usual u6/g4 meter.
If you go combi then fit wondervalves with suiatble flow restrictors in them, on each outlet, so it doesnt rob the hot water from shower etc.

 

[sparra1100]

its not that i dont no unvented proberly would be better,but theres nowhere for the cylinder to go even tho its a new extension because its already be done bu the plans and would mean changing them and more expence a worcester 440 is 20 litres a min and the 550 is 25 ltr min so if thats not enough i dont no what is,plus the bloke wants a combi prefably

 

[goz666]

its not that i dont no unvented proberly would be better,but theres nowhere for the cylinder to go even tho its a new extension because its already be done bu the plans and would mean changing them and more expence a worcester 440 is 20 litres a min and the 550 is 25 ltr min so if thats not enough i dont no what is,plus the bloke wants a combi prefably

If he insists mate and you've given him the options, draw up a contract for him to sign waiving any comebacks for design or installation flaw and fit what he asks for. That's what I do in the same circumstances, sometimes customers put you in impossible positions, and you have to PYA at all times.

 

[SimonJohns]

What about a ideal istor?

 

[grahamgas]

or a glowworm ultrapower 170.

 

[sparra1100]

What about a ideal istor?

not into ideal mate wouldnt fit one given to me,dont no much about the glowworm 170 mate would have to read into it why do ye both mention them boiler, do ye not rate the worcester i dont myself but carnt see anything else with a high flow rate

 

[SimonJohns]

The intro has a 230 l store rather than the smaller in a worcester

 

[goz666]

I rate the Vaillant 937. Nice easy fit, just need a good strong wall to hang it on as the depth if i remember right is almost 600mm, the only thing I didn't like was the crappy internal filling link so I left it in and put an external one in anyway.

 

[dancinplumba]

what about two boilers ? one in extension ?

 

[sparra1100]

what about two boilers ? one in extension ?

ye thats an option already got a 30kw in, dont no what tho and how old and was thinkin of 42 cdi with it wont no properly till go the job but just exploring options at the mo

 

[SafeGasInstall]

fit whatever they want , just mention on your quote that is not you that has made decision over type of boiler/system to fit !

 

[mikeygas]

What about a viessmann storage combi? they come with either a 100litre or a 180litre internal store.