To think central heating giving up the ghost in the cold is a fairly major flaw?

[BlackForestCake]

So apparently gas central heating works perfectly in the summer when you don’t need it and in the winter unless it gets really cold.

If there is a particularly cold snap and temperatures get down to –7ºC or so, the condensate outlet pipe freezes solid, then your boiler starts making alarming gurgling sounds and the whole thing stops working, leaving you freezing with no heating or hot water.

I do not claim to be an expert but surely this is something of a design flaw if crucial household equipment stops working precisely when you most need it?

My next house is going to have a coal fire.

That's why you insulate that pipe

Can’t you just get the outlet pipe well insulated to stop it freezing?

We've had central heating for over 20 years and this has never happened.

But good luck with your forward thinking, modern heating 😉

My condensate pipe is indoors as there is a waste pipe next to the boiler. My mums froze though as its along the side of her house. It even had insulation on it and that didn't help. Boiler guy had to cut the condensate pipe near where it exited the house to get the boiler working again

Never had a problem - and we've had cold snaps with -7 before - when kids were young in midlands had a cold snap that went on for weeks well below freezing lost a tree - used to more clement climate - as it was too cold too long.

My parents have had central heating for even longer -- nearly 4 decades - with very cold snaps and never had this happen.

I’m sorry you missed it but there were warnings in the press and on the energy provider websites to keep an eye on your condensate outlet pipe. You’ve learned that lesson the hard way and I’m not surprised you’d be bloody upset at the cost and inconvenience.

My old boiler that got replaced last year was 20+ years old and didn't have a condensate pipe. Luckily we had an indoor waste pipe for our new one to drain into.

Get a heat pump then.

Yes it's a major design flaw in condensing boilers. In order to prevent you either need to keep the boiler on (albeit at low temperature) during freezing conditions or you buy a thermal kit which uses a heating element which prevents the pipes freezing....both result in using more energy though, and make a bit of a mockery of a condensing boilers green credentials.
Just using foam insulation around the pipe won't stop freezing in prolonged minus temperatures.

you are right its ridiculous - we have an old boiler with a narrow pipe outlet and a level run outside - ie not even at an angle. They also set them too close to the wall and its difficult to insulate properly. We have insulated and still spent a goodly amount of time in and out with hot water bottles to limp it through. TO be fair we have had this happen 3 times in 15 yrs.

Check out u tube for how to insulate and also how to install heated wires to prevent issues. Ours is on an exposed wall that gets alot of wind chill I think hence the issues, insulation helps but we reached -11 which is just too much for it . We will be like for like replacing with a wider bore pipe outlet as required by regs now but also making sure decent lagging in place.

If your parents boiler is 40 years old, then it won't have a condensate pipe as condensing boilers weren't available then.

They don't have a 40 year old boiler.

They've had central heating for over 40 + years but with many boilers they've also moved locations in house. Till we bought the last house I didn't think people kept boilers for over 30 + years - we had to get whole system re-done and moved and frankly the people fitting couldn't believe how old that system was.

No-one I know has had the issue OP has sounds like she been unlucky to have a badly placed condensate outlet pipe and was unaware of it could cause problems.

It's not a design fault in boilers, it's an installation issue. Insulation of the pipe and the addition of trace heating will mean it doesn't freeze. That's why big buildings have lagging and trace heating on external pipework.

We run our central heating 24x7 with a minimum temperature of 18.5°C.

The problems stem from the UK's backwards beliefs in only heating the house twice a day.

There is another thread where people have experimented with 24x7 heating and the costs are pretty much the same as only heating twice a day.

If you have a modern system, it can actually work out cheaper heating 24x7.

Depends on your house, insulation etc. My DP tried it in their stone built, 100+ year old end of terrace house when they got smart meters and a hive thermostat. Was definitely not cheaper.

I've not tried it (60's semi, cavity wall insulation, loft insulation), but I don't want to sleep with the heating on - I always have a window open at night, so I'd be throwing money away. Having the thermostat on 17-17.5 from 7.30-20.00 has led to the heating being on 5-6 hours a day when it was cold last week.

Burning more gas is not cheaper, no matter how you do it. Running the heating when you’re either away or in bed, is simply wasting the gas. A combo-boiler, like a heat pump, should be running with a steady low grade heat that allows it to remain in condensing mode longer. If you go outside and see houses when it’s cold with flues pumping big gouts of steam into the sky, that’s then running too hot and wasting energy (or not being combis, which is the same thing).

I have my thermo sat at 18°C between 0730 and 2230 on weekdays, but that’s because my partner works at home. When I was single, it was off outside a brief warm up for an hour in the morning, until I got in at 1700.

My DM's pipe froze twice in one day last week, despite engineer removing long icicle and pipe being in the sun until 4.5 hours before it froze again - engineer put industrial lagging on it a few years ago after similar problems. -8c and lower seems to be point problems kick in.

DM has no other heating and engineer came out in evening and literally cut through internal pipe so it could drain into a bucket. Not sure what he's gone, but he's been back this morning and put some sort of flexible pipe on there with something on it which needs to be pushed/pulled and apparently it'll divert flow elsewhere ahead of very low temperatures.

There's no design flaw

Just 'humans who don't know about lagging' flaw...

That's the old fashioned thinking.

Why heat, that leaves your house as it cools between morning and evening heating periods, just needs to be replaced - net gain of zero.

Modern boilers can modulate their output down, so 'hours on' does not equal 'gas burned'.

When your house has cooled by a few degrees, the heating has to go full whack for an extended period, this will cause the water return temperature to rise and the boiler efficiency to fall. Maintaining a temperature requires the boiler to do multiple small heating sessions on minimum power. The return temperature will barely rise and the radiators will barely get warm. The boiler will always be condensing and the efficiency will be higher. This is why it can be cheaper and there's no danger of pipes freezing and expensive repair bills.

How much is an emergency plumber? How much heating would that have bought?

No it's an installation flaw. That condensate pipe has not been fitted correctly and needs insulating.