combi boiler

[jeepster]

The water runs hot then cold no radiators on help please.

[blueblade]

It is usually caused by someone in another room pulling the flush.

Happy to help.

[tigerbaybluebird]

It's knackerd get a new asap

[Welshcake.]

It's the thermostat cycling.

[BLUETIT]

It is usually caused by someone in another room pulling the flush.

B 2 B.

[celticknight]

Does it eventually warm up again? Or does it stay cold?

[jeepster]

Does it eventually warm up again? Or does it stay cold?

It does get hot then cold again

[BLUETIT]

Does it eventually warm up again? Or does it stay cold?

It does get hot then cold again

B 2 B.

[jeepster]

Does it eventually warm up again? Or does it stay cold?

It does get hot then cold again

After it gets cold, does it get hot again.

then cold

[Maxim]

Does it eventually warm up again? Or does it stay cold?

It does get hot then cold again

After it gets cold, does it get hot again.

B 2 B.

What make is it.?

[Biggy G]

The water runs hot then cold no radiators on help please.

Sounds just like my mrs

[ragbone]

Check the bar rating it should be between 1 or 2

[chepstow]

The water runs hot then cold no radiators on help please.

Pressure problem should be above 1bar or the boiler wont faire up or will stop

[welshden]

The water runs hot then cold no radiators on help please.

Do your radiators get warm at all. I had a problem once where the radiators were on but the water was running hot then cold. It turned out that the shower mixer was broke and the cold water was backflowing throrough the hot water in the mixer and shutting off boiler. This can happen with any faulty mixers.

[jeepster]

The water runs hot then cold no radiators on help please.

Do your radiators get warm at all. I had a problem once where the radiators were on but the water was running hot then cold. It turned out that the shower mixer was broke and the cold water was backflowing throrough the hot water in the mixer and shutting off boiler. This can happen with any faulty mixers.

Radiators are all working fine.

[welshden]

The water runs hot then cold no radiators on help please.

Do your radiators get warm at all. I had a problem once where the radiators were on but the water was running hot then cold. It turned out that the shower mixer was broke and the cold water was backflowing throrough the hot water in the mixer and shutting off boiler. This can happen with any faulty mixers.

Radiators are all working fine.

So if the radiators are fine do you have any mixer taps in the house or showers with a thermosatic valve. All my cold water pipes to taps or shower have quarter turn isolating valves so I turned them all off on the cold side on mixer taps or shower then tried the hot water and all was ok. I then turned each one of the isolating valves back on one at a time and trying the hot water, I eventually worked out which mixer tap was allowing the cold to flow back to the hot pipes and shutting the boiler off. If you find that by isolating a particular mixing tap the problem goes then you can either change the mixer tap or put a non return valve in the cold supply to the mixer tap giving problem.

[jeepster]

The water runs hot then cold no radiators on help please.

Do your radiators get warm at all. I had a problem once where the radiators were on but the water was running hot then cold. It turned out that the shower mixer was broke and the cold water was backflowing throrough the hot water in the mixer and shutting off boiler. This can happen with any faulty mixers.

Radiators are all working fine.

So if the radiators are fine do you have any mixer taps in the house or showers with a thermosatic valve. All my cold water pipes to taps or shower have quarter turn isolating valves so I turned them all off on the cold side on mixer taps or shower then tried the hot water and all was ok. I then turned each one of the isolating valves back on one at a time and trying the hot water, I eventually worked out which mixer tap was allowing the cold to flow back to the hot pipes and shutting the boiler off. If you find that by isolating a particular mixing tap the problem goes then you can either change the mixer tap or put a non return valve in the cold supply to the mixer tap giving problem.

Cheers will try this.

[welshden]

The water runs hot then cold no radiators on help please.

Do your radiators get warm at all. I had a problem once where the radiators were on but the water was running hot then cold. It turned out that the shower mixer was broke and the cold water was backflowing throrough the hot water in the mixer and shutting off boiler. This can happen with any faulty mixers.

Radiators are all working fine.

So if the radiators are fine do you have any mixer taps in the house or showers with a thermosatic valve. All my cold water pipes to taps or shower have quarter turn isolating valves so I turned them all off on the cold side on mixer taps or shower then tried the hot water and all was ok. I then turned each one of the isolating valves back on one at a time and trying the hot water, I eventually worked out which mixer tap was allowing the cold to flow back to the hot pipes and shutting the boiler off. If you find that by isolating a particular mixing tap the problem goes then you can either change the mixer tap or put a non return valve in the cold supply to the mixer tap giving problem.

Sorry forgot to mention, a quick way to check if you do have a backflow of cold water through the hot water is to disconnect the hot water out pipe from the boiler and if there is water continually coming from the house side of the pipe then it is more than likely cold water coming through a broken mixer or shower valve.

[welshden]

The water runs hot then cold no radiators on help please.

Do your radiators get warm at all. I had a problem once where the radiators were on but the water was running hot then cold. It turned out that the shower mixer was broke and the cold water was backflowing throrough the hot water in the mixer and shutting off boiler. This can happen with any faulty mixers.

Radiators are all working fine.

So if the radiators are fine do you have any mixer taps in the house or showers with a thermosatic valve. All my cold water pipes to taps or shower have quarter turn isolating valves so I turned them all off on the cold side on mixer taps or shower then tried the hot water and all was ok. I then turned each one of the isolating valves back on one at a time and trying the hot water, I eventually worked out which mixer tap was allowing the cold to flow back to the hot pipes and shutting the boiler off. If you find that by isolating a particular mixing tap the problem goes then you can either change the mixer tap or put a non return valve in the cold supply to the mixer tap giving problem.

Sorry forgot to mention, a quick way to check if you do have a backflow of cold water through the hot water is to disconnect the hot water out pipe from the boiler and if there is water continually coming from the house side of the pipe then it is more than likely cold water coming through a broken mixer or shower valve.

Hi Jeepster if you find out it is a mixing tap causing the problem put a non return valve in anyway as it stops the problem happening again if the mixer goes faulty in future and also the non return valve goes on the hot side not cold as I previously mentioned, sorry typo error. The aim is to stop the cold flowing into the hot side.