Essex Flange Questions

[TheScullster]

Does anyone have a link to a picture of one of these? Spent ages googling to no avail! How are they fitted?

I have a grade 3 cylinder which I believe is probably the cheapest and nastiest currently available. Is this correct? Presumably because the head rating is only 10m (as opposed to 25m for Grade

1) the wall is wafer thin?

Can I still fit an Essex flange to this and hope to get a leak tight joint?

The cylinder is quite tall, with the coil tappings in the bottom 1/3 of the height. Shower pump drawings I have looked at show the Essex flange only 2" below the top dome horizontal seam. Would the flange be better lower? I assume that the internal heating coil does not project above the top external boiler connection?

TIA

Phil

[Christian McArdle]

You should always budget time and money for a replacement when doing anything to a hot water cylinder. However, an Essex flange is actually one of the things that is less likely to cause hot water cylinder failure. Replacing an immersion is far more likely to cause damage.

If you put it lower, there will be a number of effects. You may not get quite the same temperature out (which shouldn't be a problem, as shower temperatures are well below HWC temperatures). You will also run out quicker. This can be an advantage, as when the shower runs out, you can still get hot water out of other outlets, to wash hands or for filling the washing up bowl. Obviously, put too low and you won't be able to have a long shower.

Christian.

[Capitol]

2" down is quite adequate on a domed cylinder. This puts the take off about 6" down from the dome, which is the same as a Surrey flange. The flange has rubber washers on each side to help with sealing. It's frequently easier to remove the immersion heater before fitting as this gives more access and finger space. Loop a piece of wire through the flange, washers, nut and the tank before fitting, that way you don't drop the bits into the bottom of the tank! You can remove it after fitting.

Regards Capitol

[Bob Mannix]

They come in seven parts.

1. Monkey metal "T" bar with hole for string at the end of the "T" upright
2. Threaded boss
3. Split metal washer
4. Rubber washer #1
5. Rubber washer #2
6. Plain metal washer
7. Nut

Fitting:

1. Drain tank
2. Remove insulation to enable (2)
3. Drill appropriate hole in side of tank 6" down from top with hole saw.

3a. If water comes out, drain tank some more, one-handed and swearing, while putting finger over hole (pilot hole only hopefully) - sorry that was just me :o((

1. Curse because copper disk you cut out fell in tank, oh never mind.
2. Clean up edges of hole
3. Tie a long piece of string to the tie bar
4. Feed items 2-7 above on to string (in that order)
5. TIE STRING TO SOMETHING SOLID
6. Drop "T" bar and boss through hole on string
7. Feed split washer (bigger than hole) through hole by inserting edge of hole into split in washer and rotating washer (bit like fitting a key to a key ring) - if you are wondering, that's the clever bit.
8. Push 1 rubber washer through hole
9. Using gentle pull on string, get threaded boss to poke out through hole, seating on the split metal washer and the rubber washer.
10. Put outer rubber and metal washers onto boss
11. Thread nut onto boss
12. Tighten but not enough to distort tank
13. If happy with the fitting, pull hard on the string. The "T" bar will collapse and come out through the hole.
14. Fill system
15. Tighten nut some more now tank is stronger

HTH

Bob Mannix

[Bob Mannix]

Sorry two mistakes in the below:

Step 2 should have said ... to enable(3)

ADD step 16a: Make connections to boss at least to isolation valve so that water doesn't pour out when doing 17. PLEASE DONT FORGET THIS ONE!

[TheScullster]

Bob

Excellent step by step guide thanks for that.

Can you clarify a couple of additional points please?

Any additional sealing on gaskets - boss white?

150 below top of cylinder - does this equate to 50mm below top dome/cylinder top seam? Does/should final tightening operation distort tank wall to flatten?

Finally, do the rubber washers age harden and start leaking soon (how long ago did you do this)?

Thanks again

Phil

[Bob Mannix]

No, no, a thousand times no! IMHO the use of Boss White indicates a failure of procedure elsewhere. Clean the surface well, both inside and out where the rubber washers will be and deburr the edge of the hole with whatever.

dome/cylinder

Sorry, my age betraying me, 6" indeed! In reality it's not critical. Just come down from the seam a comfortable amount. The copper will be harder near the seam (probably) and you want to clear that at least.

Unless you have a very old tank, yes! Not sure what happens with a very old tank. Anything put in in the last 20 years will flatten easily locally round the hole.

About 5 years or more. The washers are absolutely fine and there hasn't been any weepage from the flange (unlike the pump, which had to be replaced). You will need an isolating valve (full bore ball valve I used) between the tank and the pump (and between the cold feed and the pump) as the pumps DO go and DO need to be replaced :o(.

To be honest I can't remember the external fitting on the flange. What I mean is, it's definitely 22mm not 15mm but I have a suspicion it doesn't have a 22mm compression fitting end on it and you have to fit an adaptor. If you want, I can check tonight. If I get sufficiently motivated, I may even take a picture.

Bob