Location of UF manifold, distance from boiler

[gdal]

Playing around with layouts for the refurb. We may have the boiler in a small ‘outhouse’ that was probably once an outside toilet. How close does the manifold need to be to the boiler? Can it be say 15 metres away in the utility room? Or should we put the boiler in the utility room as well, have the manifold right next to it and use the outhouse to keep wine?

any thoughts welcome 

thank you

[PeterW]

Not an issue with distance to the manifold - just insulate the pipes properly. 

[Nickfromwales]

47 minutes ago, gdal said:

Or should we put the boiler in the utility room as well, have the manifold right next to it and use the outhouse to keep wine?

Having the boiler outside of the heated envelope is a bad idea, as the waste ( latent ) heat loss from all the connective pipework plus the boiler itself will simply go to waste, plus when the temperature surrounding the boiler drops, that ratio for heat loss increases significantly. Also, you'll likely need some type of buffer tank or low loss header to connect a low temp heating system, such as UFH, directly to a boiler.

  

Boiler in utility, wine in cool room  

38 minutes ago, PeterW said:

Not an issue with distance to the manifold - just insulate the pipes properly. 

+1

Edited April 4, 2021 by Nickfromwales

[gdal]

I should have been clearer: the 'outhouse' is in fact attached to the main house, and shares a party wall with the kitchen. Although it is indeed outside the heated envelope, a pipe run to the inside would be less than 1 metre. I see that some boilers are available/sold as being suitable for outside installation eg https://www.worcester-bosch.co.uk/products/boilers/directory/greenstar-danesmoor-external-system

 

Since we are doing a big refurb, I was thinking to insulate this outhouse to a decent level and install an 'outside' rated boiler in it. My concern then was just how far away from the manifold it can be. In my current thinking the distance between the boiler and the manifold would be about 15metres.  Effectively all of the pipe run (apart from maybe 0.75m)  will be inside the heated envelope.

[Nickfromwales]

15m is no problem at all. 
In any kind of “half decent” outhouse, eg draught-proof and weathertight, you will be fine with a regular domestic boiler. The requisite will simply be for a frost stat ( if the chosen boiler doesn’t already have one ) and all the pipework ( in particular the condensate drain ) are super insulated. 
The question has to be, why would you put it out there if there is a better place ‘indoors’? 

[dpmiller]

is indoors ever really a good place for an oil boiler tho?