No Hot Water

[Jaroson]

Hello, another problem for the forum. Our central heating pump was replaced as the radiators weren\\\'t working. We did have hot water although now with the pump fitted we no longer have any hot water and the boiler isn\\\'t firing up often enough to heat it. The radiators are now working fine. Any advice?

I should add that it doesn't say exactly which boiler it is, but gives me a choice of Majorca 246 or Galaxie 246, both of which have a braceted (N), and upon further investigation, the pump is a Wilo Gold 50 which is set to pump speed 3.

 

[ChrisR]

Check for an air bleed point in the airing cupboard. Any of finger, screw, pliers or small spanner will be needed to open it.

 

[Jaroson]

Thanks. I'll give it a try now.

 

[pannierstan]

DHW is on gravity and if they drained the system to replace the pump then the circs to the cylinder are probably airlocked.

 

[Jaroson]

I've checked for an air bleed point, but I can't seem to find one. Then again, I'm not exactly certain what I'm looking for.

The only nuts are the ones actually flush against the tanks themselves and these look more like pipe nuts than air bleed nuts.

The DHW is a gravity flow. How would I unblock any air in the circs if this was causing the problem?

 

[pannierstan]

The DHW is a gravity flow. How would I unblock any air in the circs if this was causing the problem?

You have to boil the water by removing the stat from its position on the Heat exchanger on the boiler.
Problem is you wont be able to reach that!
If you cannot get the **** who didnt do his job right to come back try turning off the heating then turning the stat up full on the boiler and wait for an hour.
Another thing did he drain the system?? you havent said.
If he didnt get in the loft or find your central heating header tank and make sure the ballcock is free

 

[Jaroson]

Thanks. I'll give that a try now too. The hour begins...

 

[pannierstan]

Check the header tank is full.

 

[Jaroson]

Yes, that's the top tank right? It is full of cold water and fills when I run the taps. Checked that with my fingers and can feel the water level.

Apparently our hot water tank doesn't have a stat on it (according to the guy who did the job) and I can't find one myself so I guess he's right on that one. Unfortunately I was out whilst he was fitting the pump so I don't know what he has actually done, although I do know he drained the rads and the water tank. (but only after there was no hot water - so he says)
Just checked the ball cock and it's free.

 

[Jaroson]

OK, I've had the stat on the boiler turned up to max, there was water in the high tank and I switched off everything for an hour. I've switched the water and CH on again with the same result of no hot water, but piping hot rads.

Any suggestions? (Girlfriend currently filling a bowl with hot kettle water for old tin bath in front of fire back up plan)

 

[scaby]

your checking the wrong tank there will be a smaller tank just like the big one,with a ball valve, is there a valve on the pipes to or from the side of the cylinder?

 

[Jaroson]

I can only find two tanks in total. The first is an insulated round tank which has a hot water feed valve. I am assuming this is the hot water tank. The hot water valve is turned on. Pipes then go up to a second tank above it, not round, but smaller, which cold water pours into whenever I run the taps. It has a ball cock which appears to be working correctly.

Do I have a third tank elsewhere?

 

[scaby]

yes, there should be a small tank that feeds your central heating

 

[Jaroson]

Ok, thanks. I'm going for a look around.

 

[Jaroson]

Ok, I've been in the loft. There's no third tank up there so I took a look at all the pipes I've got back in the airing cupboard (it's a tall airing cupboard.) All connections end in the top tank (from the cylinder) and there are pipes from the base of the cylinder, one of which I believe leads to the hot taps and a connector of pipes on the other side which I am assuming runs to the rads. There's definitely no third tank in the house. I'm in a small two bedroomed terrace with no hidden cupboards or anything and the loft is completely bare with the exception of old books and the like.

Would it not be possible for the central heating and the hot water to run from the same supply source? Although saying that, the top tank doesn't fill when the CH comes on. Now I'm really confused!