Taking on a fixer upper House: stage 1 central heating...

[sigarland1987]

Hey all,

so as life does at the strangest times a house has appeared that me and the wife can both see massive potential in...it needs work which we will be able to do due to equity in our current house,

what I wanted to ask I would like first of all is to get the house sorted with a new heating system, realistically a combi boiler, what prices would I be looking at with consideration and what factors would be considered with regards to the new heating system.

I know am taking on a lot of work but it is a chance to get a house that is a huge step up from our current house and has potential to be made into a family home etc.

Thanks as always for your guys help,

[Aspman]

Starting from scratch would a solar heating system be a good idea?

 

Mate of mine has this in a new build. Feed in tariffs are almost irrelevant because the solar panels feed to the boiler first and heat the tank so he never really pays for hot water. Any extra then goes to the grid but only after the water is hot. Not sure if that also affect the central heating or not. Boiler is this massive stacked tank, looks like the one off the bleedin space shuttle.

 

He's as tight as an Aberdonian with lockjaw and thinks this is a great set up. He does his research so he's probably right.

Edited 30 June, 2016 by Aspman

[sigarland1987]

Hadn't even thought about Solar actually, I will have a look into it, thank you sir!

[Aspman]

I'll dig up some details from him if you like.

[SuperbTWM]

Starting from scratch would a solar heating system be a good idea?

 

Mate of mine has this in a new build. Feed in tariffs are almost irrelevant because the solar panels feed to the boiler first and heat the tank so he never really pays for hot water. Any extra then goes to the grid but only after the water is hot. Not sure if that also affect the central heating or not. Boiler is this massive stacked tank, looks like the one off the bleedin space shuttle.

 

He's as tight as an Aberdonian with lockjaw and thinks this is a great set up. He does his research so he's probably right.

 

Never heard of a set-up like that. Normally solar water heaters heat up the water directly by circulating water round the panel on the roof, it seems pretty inefficient converting it to electric first unless he has got his terminology mixed up.

 

Or maybe he is feeding hot water into the national grid... 

[cheezemonkhai]

Never heard of a set-up like that. Normally solar water heaters heat up the water directly by circulating water round the panel on the roof, it seems pretty inefficient converting it to electric first unless he has got his terminology mixed up.

 

Or maybe he is feeding hot water into the national grid... 

 

I've seen them and they tend to basically be Solar electric, but when there is spare electric left over, rather than feeding to the grid, they heat your water. Only once is that done do they feed in.

[octyal]

What about a ground heat pump? Basically the water is pumped into the ground and heated to about 65 deg C before returning to the house. Rainwater tanks could be used to store run off for "brown water" use eg flushing toilets. If that isn't practical due to location, then what about a wood pellet burner system? A few years ago my brother refurbished a local pub with wood pellet heating, underground water run off tanks for toilets, solar etc as a show piece for the owner who also had a green energy business, it even has a small domestic wind turbine - however, none of that will be of benefit if the house isn't well insulated, so that would be first on my list. Look at the insulation, get that sorted, and you may not need to spend a fortune on a fancy heating system.

[vindaloo]

Solar electric (photovoltaic cells in roof panels)  is the usual setup.... In conjunction with your usual gas boiler and rads.

 

Solar direct water heating (DIY or bought water circulating panels on roof) can be a way of reducing water of CH bill. As they pre-warm the water in the cylinder. (Needs a secial cylinder).

 

GSHP - Ground Source Heat Pump. Require a large "fridge" structure (pump(s) and heat exchangers). Work well with modern, well insulated houses when built in at the construction stage where underfloor heating may be utilised.

 

Going back to the 1st post.... Don't simply plonk a combi in there if it's "local", i.e. home counties style mega hard water. At the very least budget for a water softner plus combi.

[sigarland1987]

Don't worry would go through proper channels and do my research before actually purchasing anything. House is in Hampshire so not sure what the water is like. It's interesting the posts about solar,had never thought of it really before

['daiking']

Size of house? Budget? What about replacing rads and plumbing?

Existing house construction?

Edited 1 July, 2016 by 'daiking'

[sigarland1987]

Very true, I gave very loose details on the actual scale of the property,

 

Its a 3 bed semi detached ex council property from the 1930's current budget for the heating is upto £5000. currently in situ is a back boiler I think with water tank etc. It is 5 minutes down the road from our current property which has a Combi boiler system fitted which I really like due to the hot water on tap, as such I am just doing some research before actually jumping. 

 

Thanks all

['daiking']

Very true, I gave very loose details on the actual scale of the property,

Its a 3 bed semi detached ex council property from the 1930's current budget for the heating is upto £5000. currently in situ is a back boiler I think with water tank etc. It is 5 minutes down the road from our current property which has a Combi boiler system fitted which I really like due to the hot water on tap, as such I am just doing some research before actually jumping.

Thanks all

I'm no plumber but this is what I’ve learnt in renovating and extending my own house. A decent plumber will be able to fill in the details for you.

Forget about heating and plumbing to start with and consider the house and what you want to do with it. A 1930s semi will be a low performing house. I’d expecting it to have a cavity which could be insulated but there’s no guarantees as to how good/effective/even that will be. Suspended wooden floor? Likely to be cold and draughty. Windows? Double glazed? Old? New? Roof? Typical insulated cold roof?

Whatever those answers are, it sounds like you’re going to need a bucket load of heat in the house to keep it warm so gas probably beats direct electric resistance heating based on long term running costs. I doubt newer tech solutions would be sufficient. Solar panels – Solar PV would cost over £5k for a typical set up and with the feed in tariffs reduced I’d forget about them initially even if you went for a rent a roof scheme or borrowed the money. I would bet that heat pump stuff (ground or air) would not work without significant improvements to the building fabric, you probably don’t have the space and they would cost far too much – ground especially.

Basic modern central heating set up gives you a condensing combi gas boiler feeding direct to heating radiators and hot water outlets. Boiler sized to size of house, probably something like a 28kW or 33kW for a 3 bed would be more than comfortable and happily run a nice shower direct from the boiler with just a thermostatic shower fitting. But do you really want to connect a fancy new boiler to the crappy 25 year old steel radiators full of rust? So new radiators might be required too. Even so this basic system does away with a hot water tank or in modern parlance a “Thermal Store”. Which you would need if you went down the Solar PV route as this would give you somewhere to dump all the electricity you are not otherwise using – more cost effective than exporting it to the grid.

But consider what you want in future. Extend the house to make it bigger? Another bathroom with another shower? How is the water pressure? Hence questioning whether you should replace the hot water cylinder with added bonus of the option of an electric immersion heater if there’s problems with the gas boiler or solar PV in the future as mentioned above. Ditto something like an accumulator tank too if your pressure is low or you want to supply multiple things at once. Don’t forget bathrooms and showers etc, what do you want? I wouldn’t go back to an electric shower after a proper combi fed thermostatic shower.

And going back to my first questions, consider if there is anything you can do to improve the house at this early stage? Insulating and draught proofing etc. A gas central heating system will heat a house nicely but the better the fabric of the house is the less gas you’ll use and if you can get the boiler temperature low enough it will run at its most efficient. In hard water areas things fur up with limescale more, the hotter they run for instance as well.

Hope that’s given you something to think about but in answer to your question. Completely new basic plumbing and heating could easily be £3500 – 4000. Less or more depending on the choices you make. If you don’t understand what you want/need at the start, there are no guarantees that your plumber will either and you won’t get an appropriate solution.

[sigarland1987]

I won't quote the above, but exactly the type of answer I want with regards to this. It is a risk potentially purchasing this house but as you might have gained it is isn't being bought to be made pretty and sold on. 

 

The house itself is potentially a chance to actually have somewhere bigger and to actually have a chance to create the family home hence wanting to find out what is required and what I can expect with regards to costs.

 

Working around the above the House is double glazed and is livable at the moment. Water pressure is good round where I am based, as I have said before we have a combi boiler in the current house which is a victorian end of terraced property and has had a combi boiler fitted and sounds very similar to the basic system you describe above. 

 

It would be nice to go solar eventually but again that is pie in the sky thinking and at the moment we are taking a bit of a gamble in potentially purchasing the property as it is, but we both want a house that we can turn into ours, yes it will be a challenge and yes we are very inexperienced at this but who isn't when they start this and generally pick up things quite quickly. 

 

The house itself requires modernising and I think you are right about getting the house insulated first make sure it is actually retaining heat rather then loosing heat, it has had a new roof recently so one less thing to worry about. 

 

Cheers for your help again, lots to think about

['daiking']

I've done much the same and made many mistakes along the way. Next time, it'll be much better

[fabiamk2SE]

Sorry but running the boiler at a lower temp to save gas just isnt true on the new condensing boilers.

The hotter and harder you run a condensing boiler the more it will condense and the more effiecient it becomes. If theres no young kids around, you should be running the heating thermostat on nearly maximum. This will make the boiler more efficent, get up to temperature quicker and shut off sooner. Thermostatic radiator valves do alot to help efficiency too.

By the found of the house i wouldnt get too excited with unvented (theres a difference between thermal store and unvented cylinders by the way, theyre backwards from eachother) systems and what not as itll just be taking up valuable space and the install cost is significantly higher.

Youll likely be happy with a combi on its own if theres only one bathroom.

Bigger isnt better either. Running a 24kw combi flat out is more efficient than having a 35kw boiler ticking over, because of the above reasons.

It would depend on gas supply, incoming water pressure and what not.. But by the sounds of your house (without seeing it) a 28 or 30kw boiler would be more than up to the job.. You could even get away with a 24/25kw depending on what you're running.

Hope this helps.

I am a self employed Gas Safe installer by the way. So not just making it up as i go along so to speak .

Edited 2 July, 2016 by fabiamk2SE

[SuperbTWM]

Personally I would always go for a 30KW boiler minimum just for the hot water flow rate for the shower. If you size the radiators accordingly you can still have a decent load on the central heating side.

[Paul007]

And let's not forget planning permission and building regulations, if you're doing any new electrical work under Part P or extensions/gshp stuff that aren't permitted development.

[fabiamk2SE]

Personally I would always go for a 30KW boiler minimum just for the hot water flow rate for the shower. If you size the radiators accordingly you can still have a decent load on the central heating side.

Pointless putting in a 30kw if theres not enough water incoming though. It can only heat up what you can get to it.

And it can make the difference between having to upgrade the gas supply or not. Only allowed 1mb drop from the meter to the boiler

Edited 2 July, 2016 by fabiamk2SE

[SuperbTWM]

 Only allowed 1mb drop from the meter to the boiler

They are the regs on paper. The boilers will work safely down to around 16mb, most of them will state in the instructions.

 

When I moved in a boiler had just been installed. A 35 KW. I got a plumber round as I knew full well the last 3 meters of 15mm was going to be inadequate seen as the run of 22mm is quite long anyway. He run some more 22mm in with only the last few inch in 15mm (As the gas v/v ideal use only has a 15mm connection. He measured the pressure drop to be 16.5mB and recommended he came back and fit some 28mm for the majority of the run.

 

What he didn't know, or claimed not to know, was that my model of Ideal boiler and many others have a restrictive test port on the valve meaning that you have to factor this in. In my case on a 35K boiler you add 2mB. giving me 18.5mB from an assumed 20mB at the meter which I am more than happy with.

 

Moral of the story, trust nobody: Plumber 1 blatantly lied on the test certificate when he put down 19mB, Plumber 2 either tried to rip me off or didn't know anything about the boiler he was working on. I bet there are loads of boilers out there that don't meet the regs.

[fabiamk2SE]

They are the regs on paper. The boilers will work safely down to around 16mb, most of them will state in the instructions.

When I moved in a boiler had just been installed. A 35 KW. I got a plumber round as I knew full well the last 3 meters of 15mm was going to be inadequate seen as the run of 22mm is quite long anyway. He run some more 22mm in with only the last few inch in 15mm (As the gas v/v ideal use only has a 15mm connection. He measured the pressure drop to be 16.5mB and recommended he came back and fit some 28mm for the majority of the run.

What he didn't know, or claimed not to know, was that my model of Ideal boiler and many others have a restrictive test port on the valve meaning that you have to factor this in. In my case on a 35K boiler you add 2mB. giving me 18.5mB from an assumed 20mB at the meter which I am more than happy with.

Moral of the story, trust nobody: Plumber 1 blatantly lied on the test certificate when he put down 19mB, Plumber 2 either tried to rip me off or didn't know anything about the boiler he was working on. I bet there are loads of boilers out there that don't meet the regs.

Well a new boiler installed with more than a 1mb drop between the appliance and the meter shouldnt be left like that as its installed incorrectly and commisioned wrong.

Yes they can work down to different pressures (dependant on boiler) and can be safe and just 'not to current standards' if an engineer checks it when its already installed, but it should not be left when it is first put in.. Its against Gas Safety regs.

Yeah different boilers sometimes have different tolerances as you're checking them at the gas valve and not inlet to the boiler. A Worcester can have 2.5mb drop for instance, when checking at the inlet to the gas valve.

15mb or below will be cut off and capped as Immediately Dangerous until its resolved by a gas engineer doing his

Job properly.

I just do it by the book. I cant see why anybody wouldnt, theyre stupid not to. You have to be able to justify all your actions in court with this job, cos thats where an engineer could end up if something happens.

[SkodaVRS1963]

Starting from scratch would a solar heating system be a good idea?

 

:D :D  

 

We're in the UK?

 

You'll get enough sunshine for three eggcups of hot water every eighteen months.

[cheezemonkhai]

:D :D  

 

We're in the UK?

 

You'll get enough sunshine for three eggcups of hot water every eighteen months.

Actually not true at all.

Friend has it and in the winter it gets the water to about 40 in the summer he needs a cold water mixer on the hot taps.

[fabiamk2SE]

Actually not true at all.

Friend has it and in the winter it gets the water to about 40 in the summer he needs a cold water mixer on the hot taps.

 

Yup, theres still light in winter.. just about . 

 

Just not quite as much.