Why no hot water?

Question

I had some problems refilling my system then i discovered the tank in my loft wasnt filling up cos the ballcock was stuck. i rectified this and the system filled up, i bled the rads and they worked but im not getting any hot water from the tap.I think the tank isnt heating up. Wondering if ive damanged something beacuse the pump was running dry but i cant understand why the rads are working but theres no hot water.A fuse somewhere maybe?

Answer 1

Are you saying that there is no water or the hot tap only gives cold water,?
The hot tank is supplied ( at the bottom) from the Cold Tank, then there is a supply pipe with a vent at the top. Check the Hot tank has Water in it (tap the tank, if it sounds hollow, its empty, check the supply.)
If the Hot Water is Cold, then check the 3 port valve. The 3 port actually diverts some or all of the flow to the hot tank coil, like a radiator in the hot tank. Maybe this is choked, try cycling the 3 port by hand (lever on the side) this may move the blockage. The 3 port may be in the 'Manual ' position, under a small hook, it should be in Automatic

Answer 2

Most of the old systems like mine have a ballcock valve on the
header tank for the central heating and one on the main tank
for the inlet to the hot water tank.If you have no water out of the
hot tap the main ballcock could also have stuck, but if you are getting water out that is cold it could be an air lock.My system
works fine in the winter with every thing on but in the summer
with the pump off and the heating set for a short duration the water is luke warm and even when you turn the boiler stat right up it does not come on.If I leave the prorammer set for most of the day I have no problem.I assume my trouble to be sludge in the system, even though I recently put inhibitor in thesystem,and
gravity circulation to heat the hot water tank and perhaps the odd air pocket.In the past when I have had trouble I have connected
a hose pipe to a drain valve on one of the rad pipes and let it run
for 10mins to draw water from the tank and release the airpockets.I am no plumber but I have changed every radiator in
my house and fitted them with themastatic valves and changed
he hot water tank as well.British Gas service my boiler every year and tell me how inefficient it is and say I should have a new
one,but It has never gone wrong in 18 years apart from being a bit sluggish in the summer

Answer 3

First thing to check, have you got an old system with a seperate hot water cylinder or the modern system with a combination boiler?
if you have a seperate hot water cylinder did you check if the immersion heating element was switched off before you drained down the system? this is used as an emergency back up in case you have to turn off the gas for any reason. if this was left on then you may well have blown the element or the fuse.but this is just a side issue.
your main hot water should be heated by your boiler and it sounds like you have a problem with the three way distribution valve, this valve is used to divert the main hot water supplied from your boiler either to the hot water cylinder or the radiators. if as you say your header tank ball valve had seized up then it is quite probable that the diversion valve has also seized up, possibly with sludge, if this is the case then the valve will either need to be taken apart and completely cleaned out, or if seriously corroded then it might well need replacing completely, (unless you are competent with tools etc or have a freind who is a plumber then i would suggest that you contact a plumber for this job )
one other thing to check before going down the road of calling out the big guns, have you reset the timer on your system controller since restarting your boiler?
hopein this helps.

Answer 4

cheeky wee lass was close. if your pump was running dry then you could have damaged it. i will assume its a grundfoss but they are much the same anyway. on the front of the pump is a silver screw open (not remove ) this until water comes out. if that don't work i would check your motorised valves. because they can get stuck. move the lever over and see if they return by them selves. still not working? then i`d call a plumber that's close by. you may need a new pump or the system flushed if its an old system. but i can do no more without seeing it.

Answer 5

if its normal gas central heating it sounds more like an air lock. The pump will be fine if the rads are heating up.

this sounds like a really weird way of fixing it but read on....................get a washing machine hose,connect it to the cold washing machine valve and connect the other end of the hose to the other washing machine valve,open all the hot taps in the house,then open the hot water valve from the washing machine hose,then slowly open the cold valve on the washing machine hose.You should hear a chugging spluttering noise,the force of the cold water should push the air lock out through one of the taps.Then shut the cold valve and disconnect the hose.

Answer 6

Unless you have a system that is very differnet from what I'm thinking of, the hot water for your water tap is heated by a different system than the hot water for your radiator. Sounds like you may have solved a problem in your hot water heat but now may have a seperate issue with your water heater for your tap water.

Answer 7

I don't know where you are, but usually the hot water heater for washing purposes and the furnace for heating water to the radiators, are two different systems and not connected.

Answer 8

first of all shut the breaker off to the water heater. Otherwise it can burn up the waterheater. Then check the pilot light. if not lit light it when you turn it on. Otherwise, call a plumber.

Answer 9

I'd call a plumber out mate if I were you, I wouldnt go messing about with the water works

Answer 10

i exploit warm water for bath. And for drink, relies upon what i'm ingesting. For espresso and tea, its warm water, for chilly drink, that's chilly water with ice. For ingesting undeniable water that's commonplace water, (impartial).