Boiler/Hot Water Plumbing Solution?

accountingbod

Hi All

Any help on this would be greatly appreciated for house i'm soon moving in to:

Current Situation:

Gas fired boiler + hot water tank in bathroom and cold water tank in loft.
Solar heating on roof that gets pumped in to hot water tank.

We would like to re-do the bathroom which would mean wanting to remove the hot water tank from the bathroom (currently in a cupboard) so that there is more room.

I have had several ideas as follows:

1) Sell the solar heating panel, water pumps and remove hot water and cold water tanks and install a combi boiler. Money from sale of solar would go toward combi.
PROS - less room taken up. Instant hot water.
CONS - new combi expensive. Current boiler works okay so no need to replace straight away + lose economic benefit of solar.

2) Keep solar panel, move hot water tank to loft and raise the cold water tank enough to allow the gravity fed system to work.
PROS - no need to buy new boiler.
CONS - need to raise cold water tank (building of platform - builder, carpenter etc..), less efficient.

3) Keep solar panel, buy combi and plumb the two together? Have hard of this but not sure if possible?

basically, we want the bathroom free of the hot water tank. We would like to take the least expensive option for now providing it is not totally ridiculous!

Worth noting that at present, one of the pumps for the solar panel is broken so a replacement would be required adding extra cost.

Thanks in advance for any advice.

accountingbod

Sorry, forgot to say, the property is a 3 bed, semi-detached house.

ic

How old is the tank? Many are huge and probably could be reduced to one a much smaller size? - this would perhaps free up some space in the bathroom? It seems silly to go to all the expense of removing solar panels - I doubt their sale cost as second hand would cover the labour costs, plus you'd have a lot of plumbing and holes in the roof to make good. If they were installed with a grant, you may not even have the option of selling them anyway - without at least repaying the government for whatever they contributed to them in the first place. Is your existing boiler a system boiler?

T_T_2

Plumbing a solar thermal system into a combi boiler doesn't really make a lot of sense. You still need a HW cylinder in order for the solar heated water to provide the heat exchange so the idea of having a combi boiler that provides on demand heated water counter-acts this.

As for IC's suggestion of reducing the size of your HW cylinder, this is also not feasible as solar thermal systems fundamentally require oversized cylinders for them to work properly.

accountingbod

Thanks for the responses.

I think the tank dates back to mid 2000's maybe?
It is not huge - taller than a standard immersion tank but taller to allow the flow from the solar in to the tank i presume?

I think you are right on the combi-solar front. I have seen some kits but they are expensive and counter-intuitive to how a combi works.

So, if we were to move the hot water cylinder in to the loft, what should we be thinking about?
I'm guessing the cold water head of water needs to sit somewhere above the height of the hot water cylinder? This means raising the cold water tank.

One more thing just to make you laugh perhaps. (It is a house we are in the process of buying by the way). The house has a south facing garden yet the solar panel was placed on the north facing side of the roof???!! There may be a good reason but im struggling to find one!

T_T_2

A solar thermal cylinder will typically be of the twin coil construction which is one of many reasons why they tend to be taller than they are wide.

Naturally your cold water tank will need to be higher than your HW cylinder, but then you already know this. This distance is generally referred to as the 'head' which is why your tank will often be called the header tank. You can calculate the pressure based on the height away from any given device. So 1 vertical metre equates to just under 0.1 bar of pressure. So if for example your cold water tank was 10 meters above your bathroom shower it would present 1 bar of pressure (10m x 0.1 bar).

Canucklehead

Hi,

I would wonder about the state of the plumbing in general if someone fitted a solar panel on a north facing roof! If this is a DIY installation be very careful it may not be safe.

You need to be sure of all the detail, but from your description so far I would want to know if the panel is indeed north facing, which pump has failed and if the cylinder is gravity or perhaps thermal store.
It may be the previous owner didn't have a good enough mains pressure /flow to support an unvented system,or couldn't be bothered. Maybe you do have good mains pressure/flow.

Alpha have been marketing their Solar Smart combi preheat system for some years now.

It might be possible to utilise your existing panel with the above but would depend on it's position in the roof and flow/return connections.

Needs a site visit from someone qualified. HHIC have qualified installers in various disciplines on their database.


GSR

accountingbod

Thanks all

A visit from a professional is in order methinks.
I'll post back when i know what is going on and what the solution is - hopefully will prove to be useful to others!

Many thanks.

gas4you

Have a look at the Atmos Easy Solar.

It is designed to work with a combi, as long as the combi is ok to take pre-heated water.

Takes up very little room and is very cheap, especially as you have the solar panel already there.

T_T_2

Canucklehead wrote: »

Hi,

I would wonder about the state of the plumbing in general if someone fitted a solar panel on a north facing roof!

Absolutely nothing wrong with fitting a solar thermal panel on a north facing roof...(if you live in the southern hemisphere :rotfl:)

accountingbod

hahaha T_T

I was actually wondering if it could be the case that an australian fitted the panel!