14 replies to this topic

[FLD]

Thought I'd get some advice from the massive and it's not joes mum! I have a quandary, o have an oil fired boiler with a hot water tank. It's a pretty pitiful shower ! Now I could change to a mains pressure tank to solve it or I could go for a combi. If I go mains pressure tank this would let me use a solar cell to heat the water a bit saving oil. The thing that's on my mind is that I hardly use any oil heating the water so is it really worth it over the convenience of a combi. Baking my head this one! Current boiler is a heatslave 22/32 or something like that.

[ayresyy]

 If it all works ok apart from the low pressure issue, you could just fit a pump to bring the hot water pressure up?

[FLD]

Yeah, I did consider that. The tank is a bit small too. Second one in the shower has to get a move on!

[ayresyy]

 In that case I would lean towards a combi; only heat what you need when you need it, and no tank to install or worry about in the future.

[FLD]

In that case I would lean towards a combi; only heat what you need when you need it, and no tank to install or worry about in the future.

[Malcfin]

What is your hot water requirements? That’s the first question. If minimal (ie no more than two showers at the same time) then an oil combi is fine, forget solar as not worth the money in this country as takes years to recoup. Oil combis are great as they have storage and give loads of hot water.

[Ivor]

Don't go to a combi, or rather don't remove your hot water tank, change your hot water tank (larger better insulation, modern ones drop as little as 1 Deg a day) and fit a pressure pump. Use surplus solar energy to heat your water, friends have permanent hot water and never use the boiler for hot water

[Madmitch]

We have solar panels (water, not photovoltaic) and an immersion heater, set to run only at night on cheap electricity, for the winter when sunlight is limited.  Always hot water on tap plus mains water pressure for the showers plus no oil deliveries or gas explosions to worry about.  Yes, we are in the South of France and it can get very hot in the summer but we are also on a hilltop and we get down to -8C to -14C in the winter with wind all year round.  We installed this system in 2005 and apart from some servicing it has served us well.  It is impossible to know how much we have saved given all the other stuff pulling electricity but I reckoned about a twenty year payback and I would think that is still about right.  Prices today are lower so quicker to amortise.

[kipper]

Don't go to a combi, or rather don't remove your hot water tank, change your hot water tank (larger better insulation, modern ones drop as little as 1 Deg a day) and fit a pressure pump. Use surplus solar energy to heat your water, friends have permanent hot water and never use the boiler for hot water

we have a mains pressure system and it's great. Before we built our extension the house was a served by loft mounted header tanks, with terrible pressire problems. All of the showers had to be boosted with pumps, and the size of the immersion tanks were small, so there was always a rush to get in first! now with the much larger mains pressure tank, there is not the worry of a cold shower.
we have an oil field condensing boiler ( no mains gas). My PV array dumps excess power to an immersion heater in the mains pressure immersion tank, providing enough for two showers a day, just from solar (a good sunny day).

we are happy!

[FLD]

Thanks folks.

[AstonVauxhall]

I've read many, many times on PH that an oil combi isn't wise as they're not very good. 

 

I have an standard oil fired boiler and hot water tank. Cold mains pressure is fantastic. Hot water pressure is useless although the previous owner fitted a shower pump so the pressure itself when the pump is running is fine (although sounds like one is warming up a jet engine in the house). 

 

I'm not sure the pump is fitted correctly as the shower pump runs when the downstairs taps run and sometimes the flow isn't enough to make the pump kick in which makes the flow doubly worse. Not actually sure if the hot water flow is that bad on it's own to be honest. 

 

If you can keep it quiet, a shower pump might the easiest and cheapest 'solution'/bodge?

[slindborg]

Combis in general are dog sh*t

 

You could look at swapping the tank out for a megaflow, this uses mains pressure cold to force the hot out.

No pump needed etc.

[FLD]

Yeah, that was an idea. Mains fed tank. A1700 quid option.

[Nev]

My thoughts on boilers: don't marry one!

[christhegasman]

System boiler pressurised mains cylinder solar panels if you want
Combis arr great and cheap to run but have their limitations or you could fit a combi which runs your shower only and tank feed your taps heated by the combi on a stat controlled zoned system
Best of both worlds ?