Immersion tank, economy 7.

[lee j]

Low head of water can be overcome by raising the loft tank, ie constructing a staging to hold the tank higher in the roof area. I have done similar to increase the flow to showers which need a minimum of 1m. above the shower head to the base of the loft tank to give a reasonable flow.
As to the hot water air-lock problems and hot water flow - are you in a hard water area? as I have had to replace a few top cylinder outlet connectors, could be either a 28/28 or a 28/22 male iron/compression depending on the outlet pipe diameter, as they have furred up with limescale and reduced the water flow out of the cylinder. The water flow to taps is reduced and the water in the expansion/vent pipe is sucked down, plus the air above it into the tap flow pipework. This I think is what is causing the low hot water flow and air locks you have descibed. Remove top cylinder outlet joint and check/replace if clogged with limescale. Have had instances of previous joints internal diameter reduced from 28mm to less than 15mm due to limescale. In one instance to less than 4mm, causing water flow from taps to stop after a few minutes, even though taps were still open.

Lee

 

[stormer]

Here in NZ most builds are single story with water running low/low pressure with header tank. I have experienced your problem when running hot water indoors whilst running a lot of irrigation systems in the garden which had the effect of 'beating' the header tank refill causing air to be sucked into the hot system. A blast with the cold feed did the trick as our Immersion tanks are vented to atmosphere through the roof. We have considered changing the immersion tank to mains pressure type but that can in itself cause more problems.

 

[Centaur]

Low head of water can be overcome by raising the loft tank, ie constructing a staging to hold the tank higher in the roof area. I have done similar to increase the flow to showers which need a minimum of 1m. above the shower head to the base of the loft tank to give a reasonable flow.
As to the hot water air-lock problems and hot water flow - are you in a hard water area? as I have had to replace a few top cylinder outlet connectors, could be either a 28/28 or a 28/22 male iron/compression depending on the outlet pipe diameter, as they have furred up with limescale and reduced the water flow out of the cylinder. The water flow to taps is reduced and the water in the expansion/vent pipe is sucked down, plus the air above it into the tap flow pipework. This I think is what is causing the low hot water flow and air locks you have descibed. Remove top cylinder outlet joint and check/replace if clogged with limescale. Have had instances of previous joints internal diameter reduced from 28mm to less than 15mm due to limescale. In one instance to less than 4mm, causing water flow from taps to stop after a few minutes, even though taps were still open.

Lee

Very soft water here in Mid Wales, Lee. Never had any problems with limescale. I think the problem is air in the system. :-0)

 

[derek kelly]

Didn't know economy 7 was still going, we had convector heaters in our house in Chelmsford on economy 7, worked ok till about 4pm then the heat disappeared .

 

[noobie]

It's on the rise again Derek as many new developements refuse to pay for gas supply

 

[Centaur]

Didn't know economy 7 was still going, we had convector heaters in our house in Chelmsford on economy 7, worked ok till about 4pm then the heat disappeared .

We get 7 hours in the night , Derek. Works well apart from the price of about ?2400 pa for all electric. Mind you the washing machine, tumble dryer, hoover, dish washer and iron are used virtually every day during peak time.

 

[lee j]

We get 7 hours in the night. Works well apart from the price of about £2400 pa for all electric. Mind you the washing machine, tumble dryer, hoover, dish washer and iron are used virtually every day during peak time.

Why not put in timeswitches to run d/w w/m and t/dry overnight on the economy 7? Do that here and are all electric (apart from oil central heating) and have an annual elec. bill of less than £500 (although I would not like to be the one to throw SWIMBO out of bed to do the ironing between 2400 and 0700 :whi5tl: )

 

[Centaur]

Why not put in timeswitches to run d/w w/m and t/dry overnight on the economy 7? Do that here and are all electric (apart from oil central heating) and have an annual elec. bill of less than ?500 (although I would not like to be the one to throw SWIMBO out of bed to do the ironing between 2400 and 0700 :whi5tl: )

That's a bit like being a virgin apart from the local rugby club team. Heating is by far the biggest part of my lecky bill as I refuse to live in a cold house. Been there and done that when I was growing up. 8ree!

 

[andyBeaker]

We get 7 hours in the night , Derek. Works well apart from the price of about ?2400 pa for all electric. Mind you the washing machine, tumble dryer, hoover, dish washer and iron are used virtually every day during peak time.

I thought it was just this household - when I load the dishwasher it comes on in the small hours when everyone is asleep. When 'others'h1d1ng2 do it the machine has to be on straight away and I refuse to get up to close the kitchen door to shut the noise out on principle.

Ditto washing machine. Although I don't load that:-0)

Modern gas boilers are amazing though - we have just had a Valliant installed, two 30 minute blasts a day gives us more than enough hot water in the cylinder for the two of us including power showers for both.

 

[stormer]

Our night time economy system is actually a separate wiring from the mains in meter to the consumer unit and we have the immersion tank and one storage heater wired to it. We do not have gas here only bottled.

 

[bmwdumptruck]

Following a new main element the wife complains the burbling of the tank is waking her up in the night. The tank is obviously in the bedroom and has a louvre door, I assume for ventilation. Am I going to cause a problem if I put a plywood backing on the door to cut down the noise. The tank is very well insulated with a thick solid foam covering. Sensible help initially would be appreciated. :-0)

Sounds like you've had a cheap n nasty immersion fitted. Only real solution is probably having a better quality one fitted Bill. As you're on E7 it really should be an Incaloy one too.

It won't be scale, even if you were in a hard water area. Cylinders have had sacrificial anodes fitted for years n years now, they stop scale sticking to the cylinder and pipes. And yes they work, it's been years since I removed a cyl with any scale in it, and the waters pretty hard round here.
Won't be air either as any air in the system will be in the pipes to or from the cyl, not actually in the cylinder or anywhere near the IH.

 

[andyBeaker]

He did say the cylinder was 37 years old - is scale likely to be an issue?

:dunno:

 

[Centaur]

He did say the cylinder was 37 years old - is scale likely to be an issue?

:dunno:

We don't have scale here, Andy. Very, very soft water. Like nectar with a small bushmills.:lick:

 

[andyBeaker]

I think the source of the scale that had built up in the bottom of the cylinder that I removed had actually come from the immersion itself rather than the tank. built up like the element on a kettle then dropped off. Mind you, that was with water, not sure if the same would have happened with Bushmills.

I will shortly be experimenting with a small electric pump with a built in flow switch on my hot water supply to the distant kitchen and utility which might be interesting.

Don't tell anyone though, messing with electrics AND water at the same timew;;v, I will really be slagged off on here if people find out.

 

[noobie]

Using bike logic

I had a part that needed replacing, there have been no differences, adjustments, extras but just the one part replaced. It is now noisier than before

On that basis I would guess either you have a wrong power one so it's trying harder ergo the extra noise or you may simply have had a duffer?