Baxi back boiler query

[polo1]

Hi guys, apologies in advance if some of the terminology is wrong - I'm a spark not a plumber. Got involved with this as I was asked to check the wiring on a two way valve at the home of a longstanding mate. System is a simple Baxi back boiler serving 5 rads and an indirect coil in the hwc. One zone programmer; water only heating is achieved by turning down the room stat, which closes the two way valve isolating the rads. The problem - after draining down the heating circuit to replace the two way valve and refilling, he's getting discoloured water in/from the direct hot water tap. Any suggestions as to what is causing this?

 

[Billy Bob Bob]

its a primatic system and its lost its air bubble

 

[polo1]

Thanx for the prompt reply GM. I could Google it, but can you offer a layman's explanation and is this something he can resolve himself with some basic advice from here? I should have mentioned that he will get a heat eng in if necessary, but is keen to fix himself if it is safe for him to do so.

 

[Billy Bob Bob]

how many header tanks has he got?

 

[polo1]

There is only one main storage tank in the loft (he's the bottom flat of two). This tank supplies both the cw to taps and via different supply, to the heating.

 

[Billy Bob Bob]

There is only one main storage tank in the loft (he's the bottom flat of two). This tank supplies both the cw to taps and via different supply, to the heating.

so is there a separate tank for hot water and one for heating?

 

[polo1]

Nope, only one hwc. The attic tank is just a large open top one, there is no separate heating header tank.

 

[Billy Bob Bob]

in that case its definitely primatic the filling procedure involves leaving a hot tap open,all you can try is drain it again and refill with a hot tap open

 

[polo1]

Thanks GM, appreciate your advice, esp on a Friday night. I've noted from elsewhere also to fill slowly may help. I'll pass on the advice and see how it goes over the weekend. I much prefer electrical fault finding/solving:banghead:

 

[Simon F]

:ack2:...note of caution,
:sick:...Do Not be tempted to add inhibitor to a radiator, or even worse into the cold tank!..:nuke:

 

[polo1]

:ack2:...note of caution,
:sick:...Do Not be tempted to add inhibitor to a radiator, or even worse into the cold tank!..:nuke:

Thanks. I did appreciate this but good to have a heads up!