hot water Help and information on all topics relating to your central heating, air conditioning and ventilation issues.

[lady]

i get hot water for a few minutes and then cold water comes through the pipes

[Oliver_murphy]

Lady,

Need alot more info than that.

Is is a combi boiler, do you have a hot water cylinder?does the water stay cold, or does it slowly heat up?

[lady]

is not a combi- but i do have additional solar hot water system -

the water seems to heat up in the water tank but when we use either in the shower or through the taps , it runs nice and hor for a few minutes and then starts coming cold.
if we wait for 20 odd minutes the same happens - first hot and then starts running cold.

my local plumber has put in a new diverter valve - but the problem remains

[Oliver_murphy]

How fast does the water run out of your tap? It sounds like you have a scale problem.

[lady]

very fast - no problem about the pressure through the taps.
just that the hot water runs for a few minutes and then cold

[Oliver_murphy]

I would be checking the motorised valve, and the pipes that lead into the cylinder, at middle and bottom level.

Make sure they all get hot. Sounds like its just struggling to heat up the cyl,

Oli

[ALDA]

YOU SAY YOU HAVE AN ADDITIONAL HOT WATER SOLAR POWER SYSTEM.

ARE YOU RELYING ENTIRELY ON THE SOLAR POWER SYSTEM TO PROVIDE YOU WITH HOT WATER?

THIS COULD BE WHY YOU HAVE TO WAIT SO LONG FOR THE HEATED WATER TO REPLENISH THE TANK AND TAPS.

[lady]

no i do not rely on the solar - i have the boiler set on a timer for the hot water- at present i have the immersion on as well - but though the water in the tank is hot and does run hot for a few mionutes - after that it starts running cold. the water does come out hot at first but it starts running cold - every where- the taps and shower inthe bathroom, also the kitchen and all of downstairs - there is no reduction in the pressure of the water - it does run fast but it just goes cold after a few minutes and i do not understand why.

[ALDA]

HAS THIS PROBLEM SUDDENLY OCCURED OR HAS IT DEVELOPED OVER A PERIOD OF TIME?

WHEN DID THE SYSTEM LAST PROVIDE YOU WITH GOOD, CONTINUOUS HOT WATER?

HAVE YOU HAD ANY OTHER WORK DONE ON THE SYSTEM OTHER THAN THE DIVERTER RENEWAL? (ie SOLAR ADDITION)

THE WHOLE HW TANK SHOULD BE VERY HOT TO TOUCH PARTICULARLY AT TOP AFTER ABOUT 30-40 MINS.

THE UPPER SIDE ENTRY FLOW PIPE FROM BOILER SHOULD BE VERY HOT TO TOUCH. IS IT?

THE LOWER SIDE EXIT RETURN PIPE SHOULD BE SLIGHTLY LESS HOT IN COMPARISON. IS IT?

IF YOU HEAT THE TANK USING SOLAR ONLY DOES TANK GET VERY HOT?

IF YOU HEAT THE TANK USING IMMERSION ONLY DOES TANK GET VERY HOT?

DOES THE BOILER RUN CONTINUOUSLY TO HEAT WATER OR DOES IT START STOP START STOP REPEATEDLY OR RUN THEN STOP FOR PERIOD?

SORRY TO HAVE TO ASK SO MANY QUESTIONS, BUT THE MORE INFORMATION YOU CAN PROVIDE THE MORE LIKELY IT IS, I OR OTHER SITE USER MAY BE ABLE TO RESOLVE THE PROBLEM.

ALDA.

[lady]

it is about two weeks now that the problem has occured- we have had no problems before.

no other work done - the solar was fitted about 4 years ago and have had no problem and it does heat the water with a minimum requirement from the boiler.

the tank is hot
all the pipes are hot

the use of immersion only also heats the water


the boiler runs for a while and then stops and then starts again -
seems to be working fine

the radiators are hot
the initial flow of water is hot

IT JUSTS TURNS COLD AFTER A FEW MINUTES

[Oliver_murphy]

HOw old is your cylinder? It may be scaled up, which is common in copper cyl's. Normally mean it has to be replaced.

[lady]

it is only 4 years old- it was newly replaed when we had the solar system fitted

[rocky01]

Hi how many mixer taps do you have?

[ALDA]

HAVE THE PRIMARY WATER CIRCUIT CHECKED TO SEE THAT IT IS FULLY PRIMED AND CIRCULATING WITH NO SLUDGE OR AIR LOCKS.