Baxi 105he dhw luke warm

[monkeytrousers]

hello all

dhw on a baxi 105he not reaching temp, the standing gas pressure is correct at 20mb but only reaches 15mb when the hot tap is on full, I think this indicates a thermistor problem can anyone please tell me if i'm right, I took it out and cleaned it but no change
any advice is much apreciated

 

[stevetheplumber]

hello all

dhw on a baxi 105he not reaching temp, the standing gas pressure is correct at 20mb but only reaches 15mb when the hot tap is on full, I think this indicates a thermistor problem can anyone please tell me if i'm right, I took it out and cleaned it but no change
any advice is much apreciated

inlet preasure should be 20 mb with the tap on full you have insuficent gas supply

 

[Kip]

Check the working pressure at the meter, if its below 16 i beleive then you have a governer that is nackered which gas supplier will change it, always worth checking that one..

 

[oldplumber]

working pressure at the meter should be 21mb +/- 1 mb and you are only allowed a total drop in pressure to all appliances of 1mb ie for 4 appliances 1/4 mb drop at each appliance. The meter should provide 21mb working pressure, if it doesnt call out transco to repair the meter. Check though that the pipework is adequate to allow no loss of pressure to the appliance, refer to your viper or other training manuals to remind you of the regulations.

 

[migoplumber]

check the standing pressure at gas meter. if its between 17 and 25 then its ok
if operating pressure drops below manufacturers requirements then the pipework is undersized.

cant see the relation between thermistor and gas pressure tho ?

 

[newbie1]

working pressure at the meter should be 21mb +/- 1 mb and you are only allowed a total drop in pressure to all appliances of 1mb ie for 4 appliances 1/4 mb drop at each appliance. The meter should provide 21mb working pressure, if it doesnt call out transco to repair the meter. Check though that the pipework is adequate to allow no loss of pressure to the appliance, refer to your viper or other training manuals to remind you of the regulations.

i thought you are allowed an operating/working pressure in the range 19-23mb ie 21mb +-2mb??
can someone confirm and then a 1mb drop between meter and appliance

 

[wnjswozo]

gas rate the applaince,check pipe sizing,fga it,check meter