Ok, I'm not getting hot water from my Halstead Ace combi.
First off the system wouldnt fireup, the "nipple" wasnt creating
enough pressure to actuate the DHW flow switch ie wouldnt poke out
enough.....I've artificialy resolved that and now the DHW system will
activate and fire up but it wont produce any hot water.
I've got 4 volts across the thermister(chechek its resistance compared
to the CH one, maybe 500ohm differance at room temp, the plate
exchanger is cold when there is a demand for hot water.
The water flow regulater seems fine and the filter is clean.

The CH side works fine.....help, what is the problem????

On 11 Jan, 16:40, hicky wrote:
Ok, I'm not getting hot water from my Halstead Ace combi.
First off the system wouldnt fireup, the "nipple" wasnt creating
enough pressure to actuate the DHW flow switch ie wouldnt poke out
enough.....I've artificialy resolved that and now the DHW system will
activate and fire up but it wont produce any hot water.
I've got 4 volts across the thermister(chechek its resistance compared
to the CH one, maybe 500ohm differance at room temp, the plate
exchanger is cold when there is a demand for hot water.
The water flow regulater seems fine and the filter is clean.

The CH side works fine.....help, what is the problem????

I wonder just what "I've artificially resolved that" means?
It sounds as though your analytical logic and familiarity with the
beast in front of you is sufficiently lacking to warrant calling
someone in who can deal safely with a gas appliance

On 11 Jan, 20:54, cynic wrote:
On 11 Jan, 16:40, hicky wrote:

Ok, I'm not getting hot water from my Halstead Ace combi.
First off the system wouldnt fireup, the "nipple" wasnt creating
enough pressure to actuate the DHW flow switch ie wouldnt poke out
enough.....I've artificialy resolved that and now the DHW system will
activate and fire up but it wont produce any hot water.
I've got 4 volts across the thermister(chechek its resistance compared
to the CH one, maybe 500ohm differance at room temp, the plate
exchanger is cold when there is a demand for hot water.
The water flow regulater seems fine and the filter is clean.

The CH side works fine.....help, what is the problem????

I wonder just what "I've artificially resolved that" means?
It sounds as though your analytical logic and familiarity with the
beast in front of you is sufficiently lacking to warrant calling
someone in who can deal safely with a gas appliance

Thanks for the help though.

Artificially resolved meant that when the nipple pokes out I'm
actuating the micro switch, after that I'm still getting no hot water
from the system.
£30 for a flimsy housing and micro switch that is a couple of pound at
best from cpc the price of spares takes the mick.

But again thanks for the help

"hicky" wrote in message
...
Ok, I'm not getting hot water from my Halstead Ace combi.
First off the system wouldnt fireup, the "nipple" wasnt creating
enough pressure to actuate the DHW flow switch ie wouldnt poke out
enough.....I've artificialy resolved that and now the DHW system will
activate and fire up but it wont produce any hot water.
I've got 4 volts across the thermister(chechek its resistance compared
to the CH one, maybe 500ohm differance at room temp, the plate
exchanger is cold when there is a demand for hot water.
The water flow regulater seems fine and the filter is clean.

The CH side works fine.....help, what is the problem????

My guess would be the primary side of the DHW heat exchanger blocked with
black sludge from radiator corrosion products. These can be washed out. The
symptom of this fault is that when you call for DHW and the diverter valve
operates, because the DHW doesn't pick up heat through the HX then the
"central heating" hot water from the HX over the flames gets hot, this is
picked up by the CH thermistor and the gas supply shuts off. Had one of
these a month ago, so I know what I'm talking about.

Alternatively, the diaphragm which senses DHW demand may have a hole in it,
so the plunger won't move. And on my own Halstead (Finest, Wickes 90) the
plunger goes through the middle of the diverter valve, so I think that
gummed up parts there will also stop it moving.

I have just developed a split diaphagm and the plunger seems stiff to me:
parts on order! And if you think two independent failures in a month is
unlucky, I might add that the ignition circuit failed over Xmas, requiring a
new board. All this on a five year old boiler which had a new board (kept
locking out) and an open circuit solenoid on the gas valve last winter.

Good luck!

On 11 Jan, 22:39, "newshound" wrote:
"hicky" wrote in message

...

Ok, I'm not getting hot water from my Halstead Ace combi.
First off the system wouldnt fireup, the "nipple" wasnt creating
enough pressure to actuate the DHW flow switch ie wouldnt poke out
enough.....I've artificialy resolved that and now the DHW system will
activate and fire up but it wont produce any hot water.
I've got 4 volts across the thermister(chechek its resistance compared
to the CH one, maybe 500ohm differance at room temp, the plate
exchanger is cold when there is a demand for hot water.
The water flow regulater seems fine and the filter is clean.

The CH side works fine.....help, what is the problem????

My guess would be the primary side of the DHW heat exchanger blocked with
black sludge from radiator corrosion products. These can be washed out. The
symptom of this fault is that when you call for DHW and the diverter valve
operates, because the DHW doesn't pick up heat through the HX then the
"central heating" hot water from the HX over the flames gets hot, this is
picked up by the CH thermistor and the gas supply shuts off. Had one of
these a month ago, so I know what I'm talking about.

Alternatively, the diaphragm which senses DHW demand may have a hole in it,
so the plunger won't move. And on my own Halstead (Finest, Wickes 90) the
plunger goes through the middle of the diverter valve, so I think that
gummed up parts there will also stop it moving.

I have just developed a split diaphagm and the plunger seems stiff to me:
parts on order! And if you think two independent failures in a month is
unlucky, I might add that the ignition circuit failed over Xmas, requiring a
new board. All this on a five year old boiler which had a new board (kept
locking out) and an open circuit solenoid on the gas valve last winter.

Good luck!


Thanks for a more constructive answer, the plunger is free moving just
a mm short of actuating the microswitch.
I'll give washing the exchanger a try, as I said the circuit is
activating but the DHW plate exchanger is freezing.
I'll see how I go.