Pump overrun

[OG]

This may be true, but at least he is now a better informed complete prick, which can't be a bad thing

[Roger Mills]

Yes indeed. And a few others may have been interested in the answers, too.

[Roger Mills]

Maybe. But, with an S-Plan system, water will only circulate round the by-pass loop during over-run conditions, so won't do much house heating. The main purpose then is to prevent the boiler from over-heating due to the residual heat in its metal bits. My boiler[1] would trip - and require manual resetting - very frequently were it not for pump over-run. Even with (Baxi's implementation of) pump over-run it used to trip occasionally - until I supplemented it with an external timer.

[1] Baxi Solo 70/PF Mk I

[Uncle Peter]

My Baxi (over 14 years old) has no such problem, so basically we've made worse boilers.

[Uncle Peter]

It might make them faster at heating up, but I can't see the efficiency increasing.

[charles]

My boiler is now 25 years old, It needs an overrun. 37 years ago, I had problems with our village hall heating because it needed an overrun which wasn't installed. maybe boilers are getting better

[Roger Mills]

Except that your boiler is more recent than mine - mine was new in 1991!

The need or otherwise for pump over-run is not a measure of boiler quality - but is more a function of the particular design choices made by the manufacturer. Far more important is its reliability and the efficiency with which it extracts useful heat from the fuel burned.

[bert]

Too bad.

[bert]

And in pursuing that aim pump overrun became a necessity to counteract one of the disadvantages that has already been commented on.

[Uncle Peter]

Thankyou Mr Chocolate-Teapot-Smythe.

[Uncle Peter]

Bet you've serviced yours though, mine's been untouched for 14 years.

[Uncle Peter]

Which means the boiler design is shit. It should have more water and less metal. The efficiency of converting gas to hot water won't change.

[Uncle Peter]

What is the point of having less water? My boiler works fine with a decent amount of water. And it only takes minutes for piping hot water to come out of it.

[Uncle Peter]

It doesn't have to be. Just have a basic simple boiler and pay way less= .

Some radiators and pipes failing should never cost anything like that. = You're one of those "one born every minute" people that they love.

On average, the insurance companies make money, or they wouldn't be in i= t. So unless you have something like a luxury yacht you really couldn't= afford to replace, then don't insure anything.

-- =

Why does sour cream have an expiration date?

[Uncle Peter]

Just how fast do you need your radiators heated up?

[charles]

i've cleaned the crud out of the burner area a couple of times. Is taht called servicing?

[Uncle Peter]

I was told to do that once, I found f*ck all crud.

[John Rumm]

[Uncle Peter]

It strikes me that the money you save on gas with all this "efficiency" is outweighed by the cost of the boiler and associated fitting, parts, and servicing. Same no doubt applies to fancy cars.

[Roger Mills]

I would certainly agree that if an older boiler is working reliably, it's difficult to make an economic case for throwing it away and replacing it with a newer one. The extra costs of depreciation and servicing are likely to outweigh the cost of fuel saved - which is why I've still got my 24-year-old boiler!

The same probably applies to cars if you only consider fuel efficiency - but it's nice to have things like power steering, anti-lock braking and heated seats - which older cars didn't have. I've yet to be convinced about electrically operated tailgates and parking brakes - which some of the latest cars have - though.