Combi in loft...good idea?

catchdarren

We've just had various heating companies to give us quotes to insstall a complete new central heating system in our mid-terrace Victorian house. One of them has suggested that we install the combi in the loft. It actually seems quite a good idea, there's loads of space up there, unlike the rest of the house.

Has anybody else heard of this and are there any drawbacks to this solution?

Thanks Darren

moneysavingplumber

Provided all the fireproofing and ventilation/clearance issues are addressed it's fine. If the flue is vertical its actually better from the point of view of pluming with condensing boilers. The main requirements, to ensure the boiler can be safely maintained and serviced, will be that there is loft ladder access, fully boarded joists, guard rail around the access hatch, permanent lighting (i.e. swtiched lighting, not on all the time!), and frost protection is provided (included on most combi boilers) and all pipe work is correctly lagged. The trickiest considerations are usually condensate disposal and pressure relief discharge. The condensate cannot simply push out of the fascia into a gutter, although there are condensate pumps available now and in most cases a solution can be found. The pressure relief discharge needs to be sited safely where it can be seen.

One of the biggest problems is often finding a suitable place to actually hang the boiler within a loft space, although in a mid terrace there should be sufficient brickwork.

meadowcat

DD has hers in the loft. Hers is a semi and the boiler is located on the gable wall. It seems to have worked out really well as she didn't want it in the kitchen or in a bedroom as some people seem to have.

She has the loft ladder and the light, but no guard rail round the hatch. That is a great idea - even if you don't have your boiler up there.

Thanks for all the great plumbing/heating advice you give on here MSP.

alanobrien

In short yes its a good idea.
A friend has a small top floor flat and had his put in the loft which allowed them more space in the kitchen.
They have never regretted doing it.

robowen

I'd agree with all the advice given so far.
The only downside I can think of atm, is that you only know the boiler has broken down when the heating goes off or there's no hot water. The loft is not somewhere you're going to be passing very often to notice the pressure guage dropping, indicating possible leaks in the system. I would ask the installers to fit a secondary pressure guage in a convenient location.

rob

moneysavingplumber

That is a good idea, and also ensure that the time control for the heating is situated in the living space, a wireless programmable room stat would be ideal.

basill

Ive wondered about this too, Last week I saw a row of newish houses in Milton Keynes, all had a steamy flue poking out of the roof tiles. Cant think of any disadvantages at all. Why would anyone want the boiler taking up space in the kitchen anyway?

B

chinagirl

catchdarren wrote:

We've just had various heating companies to give us quotes to insstall a complete new central heating system in our mid-terrace Victorian house. One of them has suggested that we install the combi in the loft. It actually seems quite a good idea, there's loads of space up there, unlike the rest of the house.

Has anybody else heard of this and are there any drawbacks to this solution?

Thanks Darren

I have had my gas boiler installed in my loft, as I could not spare the space in my kitchen. It is great, when its cold, I turn up the thermostat in the living room, and a few minutes later, the room feels lovely and warm, without hearing the whoosing noise the boiler makes. I would certainly recommend it. My gasman said that lost installations are alright, but you need to install a permanent loft ladder, for access, but apart from that, go for it!

catchdarren

Wow! Thanks everybody for the informative and QUICK replies. It certainly sounds like it's the way to go. My only remaining concern is picking up on what moneysavingplumber said, "The trickiest considerations are usually condensate disposal and pressure relief discharge. The condensate cannot simply push out of the fascia into a gutter". From my conversation with the GCH engineer, that seems to be exactly what he intended to do, i.e. just let it flow into the gutter. Why is this inappropriate? I'll certainly clarify this before I proceed. Thanks again for all the info, what a great lot of people!

Darren

star1_2

Sounds like a good idea - but I don't want to put a spanner in the works - just get the following checked out, regarding your mains preasure water. (measured in "bar").

But since the combi relies upon semi-decent mains preasure water to function, ensure the preasure (by the time it has made it to the loft) will be sufficient. Also make sure that you allow (+ bar) preasure to cope with any 'preasure drop' from either your water company, or caused when you draw off other water from the mains supply (eg. garden hose, washing machine etc).

moneysavingplumber

Lack of pressure is very unlikely to be a problem just by putting it in the loft. Most mains have to fill cold water storage tanks in lofts and even in three storey town houses the drop over height is negligible. It's flow-rate that's likely to be the biggest likely problem, often it can be too high causing the water to be lukewarm, it can often be adjusted by a screw on the diaphragm assembly and a flow-cup can be used to set it to the correct rate for the boiler. With combis there will always be the element of problem when another tap is opened in the property, it's part of the compromise of having a combi, which is why they are not suitable for all homes.

The condensate should discharge into foul water drainage, not rainwater soakaways. The reason for this is the acidity in the water. Purpose made soakaways can be used that are filled with limestone chippings to neutralise the acidity, but poking it into a gutter would not be acceptable. Be aware that any runs of condensate pipe work on the outside will usually need to be in 32mm plastic and will be limited in length, and will need to be lagged in theory.

http://www.worldpumps.com/product_news/pumps_rotary_displacement/041025_Grundfos_Conlift.html