Combi boiler hot water question

[stuartlake]

Does a combi boiler, when hot water is running from a tap, have a thermostat like the heating water in the heat exchanger or does it continually run, say running a bath takes 15 - 20 minutes, will it run through that time or will it cycle on and off when the stat reaches temperature

I just wondered if anyone knew as may be getting one in my new flat soon.

 

[Rico99]

Hi there,

There water will constantly at the temperature you have the boiler set to on the hot water controls and will on shut off when you close the tap

Rico

 

[stuartlake]

Ok then thanks for your help it is much appreciated. I was hearing stories of people's hot water from a combi running cold after a short while and then hot again, like cycling and it put me off. That cycling of ho and cold is not normal then and means a fault ?

 

[Rico99]

Yes its means there is a fault

 

[jacobball]

it means scaled up heat exchanger, or sludged up, (depending on type) incorrect flow rate through combi boiler or gas rate incorrectly. Even a faulty thermistor could cause it.
the hot water side of the combi has a thermostat/temerature sensor but will not reach this temperature and then cut out and won't run hot cold hot cold.

hot water will be set at say 60degrees C, when the hot tap is opened the water will run and get up towards that temp, and stay at this temperature. when you shut the tap it will stop as rico has said.

But if the temeprature gets too hot, ie scaled up heat exchanger, then the burner will go out / overheat and cycle on and off

 

[matemilo]

it means scaled up heat exchanger, or sludged up, (depending on type) incorrect flow rate through combi boiler or gas rate incorrectly. Even a faulty thermistor could cause it.
the hot water side of the combi has a thermostat/temerature sensor but will not reach this temperature and then cut out and won't run hot cold hot cold.

hot water will be set at say 60degrees C, when the hot tap is opened the water will run and get up towards that temp, and stay at this temperature. when you shut the tap it will stop as rico has said.

But if the temeprature gets too hot, ie scaled up heat exchanger, then the burner will go out / overheat and cycle on and off

im having this problem at the moment, i have a combi boiler, and water doesnt seem to just run at a temperature, it will go either really hot, or (when turn towards cold) it go really cold, i notice this when using the shower, which is a mixer shower. Do i need to call the professionals?

 

[kevplumb]

it means scaled up heat exchanger, or sludged up, (depending on type) incorrect flow rate through combi boiler or gas rate incorrectly. Even a faulty thermistor could cause it.
the hot water side of the combi has a thermostat/temerature sensor but will not reach this temperature and then cut out and won't run hot cold hot cold.

hot water will be set at say 60degrees C, when the hot tap is opened the water will run and get up towards that temp, and stay at this temperature. when you shut the tap it will stop as rico has said.

But if the temeprature gets too hot, ie scaled up heat exchanger, then the burner will go out / overheat and cycle on and off

im having this problem at the moment, i have a combi boiler, and water doesnt seem to just run at a temperature, it will go either really hot, or (when turn towards cold) it go really cold, i notice this when using the shower, which is a mixer shower. Do i need to call the professionals?

na just hijack a post

oh yeah you have

start your own thread

include boiler make / model