Worcester Bosch green star 30 cdi hot water issue

[proelitegas]

Hello all hope all is good have the above boiler providing customer with low temp on dhw. Down stairs temp 2-3 meters away from boiler temp is satisfactory but draw off points in bathroom temp is poor. Before I go order a plate heat ex is there any checks i should be doing? Any assistance would be appreciated and thanx in advance.:detective:

 

[vern]

Hello all hope all is good have the above boiler providing customer with low temp on dhw. Down stairs temp 2-3 meters away from boiler temp is satisfactory but draw off points in bathroom temp is poor. Before I go order a plate heat ex is there any checks i should be doing? Any assistance would be appreciated and thanx in advance.:detective:

Yep the flow rate is too high, check and adjust to spec, check inlet pressure, check gas rate, set up with FGA if all is good plate heat ex, normally very good on these as oversized 16 plate design, unless system is heavily fouled.

Also check with heating cold, no heat is going down CH flow when using hot tap, as div valve seat can get fouled if system is full of carp!

 

[proelitegas]

Nice one mate would you know what the ohms resistance on the dhw Ntc sensor is? Boiler was working fine until yesterday when pressure dropped. Customer turned off power to boiler and it went into purge mode that's when they called me but once purged heating ok hot water not good.

 

[vern]

Nice one mate would you know what the ohms resistance on the dhw Ntc sensor is? Boiler was working fine until yesterday when pressure dropped. Customer turned off power to boiler and it went into purge mode that's when they called me but once purged heating ok hot water not good.

Won't be thermistor pal, bullet proof, and if it was it throws a fault code, also ensure cap off auto air vent is loose, and heat ex, has no air trapped!

 

[proelitegas]

Will do mate. Thanx for you help mate..

 

[Deleted member 44451]

system full of carp mm interesting, a fisherman might question that

 

[vern]

system full of carp mm interesting, a fisherman might question that

Common, leather or mirror? Get with the programme dudette and the swear filter :devilish:

 

[proelitegas]

Hello all sorry for late update went to customers house yesterday now problem was the heating wasn't working so called technical and told th the issue they were going more towards pcb so with their instructions did a factory re set on the pcb and boiler went through its purge etc and then did start working on heating fine but dhw issue still there so it's a new plate heat ex going in today. Just a question how do you open the drain on the hydraulic block? does it turn to the right to open?

 

[Toxic Ted]

Common, leather or mirror? Get with the programme dudette and the swear filter :devilish:

Grass...........no the carp not you!!!

 

[michael c]

not sure if its the same as the junior but i think so, the instructions say to remove all the piping in lower left side of boiler (gas valve etc) and pull plate hx out from left but it is easier to cut the cold water pipe remove the 2 screws rotate 90 deg to the vertical and it will fit throtjgh the gap where the cold mains pipe was. Drain point should be a thumb tap to left of diverter

 

[ambrosia]

how many taps in the house and how many have issues, to me it sounds like the problem could be one of the mixer taps not the plate heat exchanger, in fact i'd say if at least one of the taps is okay then its not the plate heat exchanger. Also luke warm water usually points to a diverter valve not the plate heat exchanger

isolate the cold water to each tap in turn and test to see which one is letting cold water into the hot water side

 

[neily01]

Agree with ambrosia if one tap iso hot should be ok warm water more of diverter issue. Try turning off the coldmain to the boiler then open a hot tap and see if you get any flow if so cross flowing some where, have heard of this before with the cheaper bar shower mixers.

 

[ambrosia]

I know we're right, I really hope he read our above posts before putting that plate heat exchanger in, he said he was doing it yesterday, sorry prolite didnt read your thread till last night

 

[Deleted member 44451]

i had this problem , cust supplied a bar shower got it cheap someware and i was getting cold water down the hot pipe feeding the shower luke warm water in the bathroom and hot water at the sink next to the boiler downstairs

 

[AlexGas]

isolate the cold water to each tap in turn and test to see which one is letting cold water into the hot water side

…or turn off the cold feed to the boiler and open your bathroom hot taps one by one to see if any cold water is coming out.

 

[neily01]

…or turn off the cold feed to the boiler and open your bathroom hot taps one by one to see if any cold water is coming out.

Great minds think alike