Worcester 32cdi compact combi boiler and Megaflow

[alecialondon]

Hi there

First post, so be gentle :90:

We are renovating and extending our newly purchased house and it has a Worcester 32cdi compact combi boiler that is around 2 years old installed already. We are adding one bathroom (2 in total) and an additional toilet (2 in total) and we are putting in a Megaflow to ensure we have enough hot water to have both showers going at once.

Now for my query. One builder we saw advised that we could re-use the Worcester 32cdi compact combi boiler we already have and just hook it up to the Megaflow. However the builder we ended up going with has said we need a new boiler as the combi won't work with a Megaflow....

My husband and I have no idea, so we're looking to you guys to tell us the whole story!

Thanks in advance,
Alecia

 

[stani]

Don't use a builder use a heating engineer who will know what he's talking about and save you money in both the short and long term.

 

[Chalked]

Yes.
Quite usual to link up to a megaflo from a combi. Works very well, just leave the kitchen on the combi. The rest throough the megaflo.
Any plumber with a bit of knowledge can do it.

Why ask a builder?

 

[alecialondon]

Thanks for this, appreciate it. We've just started the build and I've only had the conversation with the builder so far as he is the main contractor.

 

[Destroyer2813]

As chalked says leave the kitchen/utility on combi and the rest of the megaflow get the incoming water pressure/flow checked as well to make sure it is sufficient for the megaflow first

Also dosent have to be a megaflow these are just a brand name that most people know unvented systems by there are plenty of different brands out there

 

[alecialondon]

Thanks Destroyer2813 - that is good to know. Is there any reason we shouldn't use our existing combi?

Both the combi and the unvented system will go in the loft (the existing combi location is now a pile of rubble!), would that be ok?

Also, we have Thames Water coming to assess the size of our pipes and then we will obviously get them enlarged if needs be.

 

[Destroyer2813]

No reason at all apart from its a waste of money to replace it unnecessarily

 

[Destroyer2813]

Try and get the unvented above a supporting wall where possible and don't forget loft needs boarding out a permanent means of access and a light

 

[Kev the gas]

I use a Worcester combi boiler along with an unvented hot water cylinder.

The hot water side is plumbed in but not used, and works an absolute treat.

Only suggestion would be to get the heating engineer to see if an extra expansion vessel is required due to the extra size of the property/ volume of water in radiator circuits.

Reason for a combi was the Williams Black Friday offer !!!

 

[stevetheplumber]

combis are often cheaper than the system boiler equivalent ridiculous when it has less parts

 

[mountainman]

Use a decent heating engineer, preferably one who would make sure that the boiler is easily accessible for maintenance and repair.
When I encounter one that is not, I either ramp up the cost or walk away.

 

[Riley]

Thanks Destroyer2813 - that is good to know. Is there any reason we shouldn't use our existing combi?

Both the combi and the unvented system will go in the loft (the existing combi location is now a pile of rubble!), would that be ok?

Also, we have Thames Water coming to assess the size of our pipes and then we will obviously get them enlarged if needs be.

seriously who has removed the boiler and made the gas safe? Do not let a builder do this!!!

 

[Riley]

Thanks Destroyer2813 - that is good to know. Is there any reason we shouldn't use our existing combi?

Both the combi and the unvented system will go in the loft (the existing combi location is now a pile of rubble!), would that be ok?

Also, we have Thames Water coming to assess the size of our pipes and then we will obviously get them enlarged if needs be.

seriously who has removed the boiler and made the gas safe? Do not let a builder do this!!!