Using a Combi boiler as a System boiler

[PFton]

I am currently replacing an old heat only boiler with a system boiler.
My plumber has bought a combi boiler instead of system boiler because he says its slightly cheaper and has all the same functionality.
He explained that it will still fill my hot water cylinder and work much the same way as system boiler.
His explanation seems reasonable, but are there any drawbacks to using a combi in this way? The new boiler is a Wiessmann 050 30kW.

 

[JonathanM]

I would also like to know. The only thing I have thought of to date is that there are extra, unnecessary parts to go wrong, even though they aren't actually being used.

 

[martygturner]

As you will just be using the ch loop there is no real difference in function, a boiler is heating some water and pumping it round a loop.

 

[Exedon]

Have done this a number of times over the last 10 years.
Really is no problem at all.

 

[gas112]

No problem whatsover and if you have a well used hot tap for filling sinks close by that could be linked up to the combi save using the stored water

 

[chrisbrown175]

Sorry for jumping on this thread however my question is relevant.

I currently have a Worcester Greenstar Heatslave oil combi boiler approx 3 years old.

1. Can it be used as a system boiler with a hot water cylinder?

2. I may have the opportunity to get a free heat pump and PV solar panels due to a grant for off grid homes, however i'm concerned that a heat pump will be inefficient and expensive in really cold weather (i've read the horror stories!). I hear it's possible to have a hybrid system whereby the heat pump and oil boiler work together via a manifold. The idea being that the boiler kicks in when you need a boost of heat or when the ambient temperature is low resulting in the heat pump being inefficient. Would this boiler be able to do this?

Thanks

 

[polesapart]

Undoubtedly it could be done, albeit at some expense.

Your eco grant may however be conditional upon the fossil-fuel boiler and oil tank being decommissioned and removed.

 

[Exedon]

We have certainly turned a Grant 36 kw combi into a system boiler. Disconnect heat store plate to plate pump on domestic then repiped and fitted standard controls from a heat only.
Took couple of hrs God knows on a worcester oil combi horrible things.
We have done a number of heat pump/ oil systems but they were Grant's and ment to go together.

 

[DP]

One major thing to consider is age and condition of the existing plumbing.

Going from open vented to sealed system, if existing system has weeps and leaks, pressurise at your own peril