No hot water!

[bayliner]

Hi again, third time this week end!

So I have fixed one cold rad and a noisy hissing rad and now have water pumping around the rads due to a closed valve, thanks to this forum.

I have been using my Emersion heater to heat the hot water, but now that I have the boiler working decided to use it to heat the water. I ran a test to make sure it would heat up the water, switch timer to on ( on water part) and boiler kicks in, pump seems to be pumping water as it's hot. After 5 mins boiler will not kick in, pump is still hot but water coming out of hot water Tap is cold, can anyone help. Left it on for good 40 mins but still cold water. Does it take a long time for water to heat up and should the boiler kick in more than once. Pilot light still ok.

This is a new property I have moved into and don't recall ever having a problem with previous boilers in other houses.

thanks in advance

paolo

 

[stevetheplumber]

what system do you have tank or combi

 

[tom609]

Possibly pump or motorised valve maybe air lock do your rads get hot when you put on the central heating that would eliminate the pump maybe a cylinder stat check you have one and make sure its calling for heat

 

[bayliner]

Hi Guys, it's a green tank which is gravity fed. Central heating is working, have put it on for the first time tonight. What's a cylinder stack ? Another question my boiler is kicking in now every 5 mins, is that normal. It's the first time this year it's been on so guess it's getting the house to temperature.

regards

paolo

 

[Ermintrude]

Your pump may be poor. Switch it to its top speed. Go in loft check both tanks are 3/4 full of water.

You may need to " vent" cylinder coil. Photograph it and we shall provide further advice

At a guess you may have opened bypass too much and now boiler cycling !

 

[stevetheplumber]

cylinder stat is the thermostat on the cylinder should be set at 60

 

[bayliner]

Hi and thanks for your info, I will set pump to full speed.

Boiler is still firing every five mins even when I reduce the temp at the thermostat on the wall, the pump is very very hot. What do you mean by opened bypass.

sorry but where is the cylinder coil and is it easy to photograph, sorry but plumbing is not my thing though learning a lot from this site.

Regards

Paolo

 

[Ermintrude]

Cylinder coil is in cylinder - the green thing. Photograph whole set up in airing cupboard. Remove that big silver nut in center of pump and catch the water with a towel. Carful it may be steam. Run water off till you hear a change. Pump will suddenly start pumping water apposed to air. Put screw back in.

 

[bayliner]

Ok have bled the pump, water coming out. I have turned it to max and will see tomorrow morning if the hot water is working. Now only problem left is firing of boiler every 5 mins. I have paper work showing it had a service in March this year. So seems strange, if it's not a simple fix I will call someone out.

i have taken photos but struggling to load them, keeps asking for URL.

thanks for all your help

paolo

 

[tom609]

Cylinder coil is in cylinder - the green thing. Photograph whole set up in airing cupboard. Remove that big silver nut in center of pump and catch the water with a towel. Carful it may be steam. Run water off till you hear a change. Pump will suddenly start pumping water apposed to air. Put screw back in.

If your radiators are hot dont touch the pump

 

[bayliner]

Rads are hot so no issue there.

Paolo

 

[tom609]

So your pump is good cylinder stat is usually 1/3from bottom of cyl

 

[bayliner]

Cylinder stat is set to 60, so all good there. Now going to wait till morning and see boiler is warming the water up. If you have any advice on firing up every 5 mins that would be great.

paolo

 

[bayliner]

When you say I have opened by pass, where do I find this?

thanks

paolo

 

[Clint 1979]

Hi Paolo,

Sounds like motorised valve is stuck, look in the airing cupboard where the cylinder is and you should one or two valves depending what system you have (google 2 or 3 port motorised valve to see what they look like).
On the valve there will be a lever that allows you to manually open it, slide the lever across with the programmer calling for hot water and feel the pipe coming from it (as it goes into the cylinder) to see if it gets hotter.

good luck

 

[kris]

Cylinder stat is set to 60, so all good there. Now going to wait till morning and see boiler is warming the water up. If you have any advice on firing up every 5 mins that would be great.

paolo

Hi paulo, the reason the boiler only comes on for 5mins at a time when timer is on hot water only is because the water that the boiler is heating is minimal , there's a coil inside your green tank which u can class as a radiator for an example, the boiler heats this coil which In turn indirectly heats the surrounding water in the green tank, so although the tank water hasn't quite reached 60deg the water in the coil will be up to temp quickly so your boiler will seem like its cutting on and off buts it will be working fine as long as it's fully aired,