New boiler fitted - Valiant EcoTec Plus 424 - General Questions

[kevz65]

Hi All,

I have asked these questions to my Gas Safe registered installer, whilst I don't doubt his wisdom, I'd like to check second opinions.

Yesterday I had my old floor standing non-condensing Kingfisher Potterton boiler (55% or so efficient!) replaced with a Valiant EcoTec Plus 424 boiler open vented.

The property in question is a 5 bed room, 2 bathroom house, with a gravity fed system (cold water in loft, hot water cylinder on the 1st floor, boiler on the ground floor).

With my old boiler, we just used to switch the hot water on when we needed it (and would have to wait 15-20 minutes for it to heat up, then go for a shower/bath etc.)

The installer said we should just keep the hot water on at all times for on demand hot water, and this wouldn't make much difference to gas usage/efficiency as the boiler would turn off itself when the tank was full.

My question is, is this normal usage of this type of boiler? Leaving the hot water switched on at all times?
Surely in terms of gas usage would it increase? Or not because it would only turn on when the tank temperature drops?

Thanks

 

[45yearsagasman]

If you also had a new cylinder fitted at the same time, then leaving the hot water on during the day will have little effect on gas usage as new cylinders are insulated to a high degree. I personally leave ours on from 07:30 until 22:30. Experiment with different timings that suit your life style. If you have an old poorly insulated cylinder then I would suggest changing it.

 

[kevz65]

If you also had a new cylinder fitted at the same time, then leaving the hot water on during the day will have little effect on gas usage as new cylinders are insulated to a high degree. I personally leave ours on from 07:30 until 22:30. Experiment with different timings that suit your life style. If you have an old poorly insulated cylinder then I would suggest changing it.

Thanks for the quick reply.

Our cylinder is old, but it is insulated with Styrofoam - is this stuff good enough?

 

[Agile]

Any foam insulated cylinder has reasonable insulation. You could add foam to the associated pipework though if the installer of the boiler did not do that.

Keeping the cylinder hot is normal and will not cost any more.

If you wanted to time the hot water then the only reason to do so is to avoid any noise nuisance during the night and I would usually recommend that.

Your current system will be fully pumped as the boiler requires that.

But the cylinder coil will be of rather lesser heat transfer than a modern cylinder designed for pumped systems.

Tony

 

[Steelmasons]

But the cylinder coil will be of rather lesser heat transfer than a modern cylinder designed for pumped systems.

Tony

Any cylinder fitted with a coil for heat transfer were designed to be fully pumped , cylinders designed for gravity heat transfer were fitted with an annulus.

 

[Bunnyman]

Haven't heard that word since my old Bg days wizzard

 

[Dan Robinson]

Chopped one in just before my accident. Had blown out like a balloon. Probably tripled its kw rating for a few days

 

[Doggit]

I had this type of question with an Ariston combi boiler that had a preheat option on the hot water. It basically kept firing up the boiler to keep the water in the coil hot, in order to allow hot water to come straight out of taps when it was wanted. When queried, Ariston admitted that whilst the option gave instant hot water when wanted, it did use up more gas than necessary.

If you'd had the cylinder changed, then I'd have gone along with 45years, but as you haven't, I'd be inclined to leave the settings to morning and night. You may have to experiment for a few days, take gas readings morning and night, and see if there's much of a difference.