Megaflo not heating enough water

[Saif]

Hi, I have a megaflo used for water (heating is electric), and for some reason I have found in the winter that there is not enough hot water, it only lasts for one shower. This doesn't happen in the summer for reason.

Can anyone suggest some solutions, I have checked the temperature on the thermostat and it seems fine. Would like to learn more before calling an engineer.

Thanls

 

[steadyon]

Generally (not always) the MegaFlo cyclinder will have two immersion heaters.

The lower one heats the entire cylinder and is often connected to a cheap rate night time tariff such as Economy 7.

The upper one heats about the top third of the cylinder, and is used to boost the hot water if it runs out. Usually good for one long(ish) and possibly one short shower. Usually connected to normal rate electricity supply.

If you have the above set up, ensure that both immersion heaters are switched on. If only the top one is on, you might get enough hot in summer when the incoming cold is a bit warmer, but not enough in winter.

 

[townfanjon]

Hi, I have a megaflo used for water (heating is electric), and for some reason I have found in the winter that there is not enough hot water, it only lasts for one shower. This doesn't happen in the summer for reason.

Can anyone suggest some solutions, I have checked the temperature on the thermostat and it seems fine. Would like to learn more before calling an engineer.

Thanls

How have you checked the thermostat ? If you have done it by “ clicking it “ like most , its not accurate.
Post a pic of the stat , most of them are garbage.

 

[Chuck]

Measure how many litres per minute your shower delivers by timing how long it takes to fill a known volume, such as a measuring jug or kettle.

What model of Megagflo do you have?

 

[chris watkins]

The reason for the winter / summer difference is the temperature of the incoming water, the 3kW immersions has to do a lot more work in the winter when it is cold, so you get a quicker heat up.

I bet you have both elements switched on but the bottom one has failed.

To work on these unvented water heaters the Law (Building Reg's) states you must hold a Part G (unvented hot water) ticket.
Please call in a pro who is qualified (ask to see proof), these systems can be a danger if not done correctly

 

[Saif]

The reason for the winter / summer difference is the temperature of the incoming water, the 3kW immersions has to do a lot more work in the winter when it is cold, so you get a quicker heat up.

I bet you have both elements switched on but the bottom one has failed.

To work on these unvented water heaters the Law (Building Reg's) states you must hold a Part G (unvented hot water) ticket.
Please call in a pro who is qualified (ask to see proof), these systems can be a danger if not done correctly

Thanks, you were right about the thermostat both seem to have blown, the upper one is holding on for dear life but needs changing.

It hasn't been serviced in a while either so the engineer said it may be worth descaling it too. He has quoted me £200 to change both thermostats and descale. Does this seem reasonable?

 

[Saif]

How have you checked the thermostat ? If you have done it by “ clicking it “ like most , its not accurate.
Post a pic of the stat , most of them are garbage.

 

[fezster]

The other thing to keep in mind is the ratio of hot to cold being used. In Summer, the incoming water supply is warmer so you require less hot water to achieve a comfortable 40 degree shower. In winter, you will require more hot water, so it will run out faster.

You should ensure the water is being heated to 60 degrees plus.

 

[chris watkins]

[QUOTE="Saif, post: 1023148, member: 101427"
It hasn't been serviced in a while either so the engineer said it may be worth descaling it too. He has quoted me £200 to change both thermostats and descale. Does this seem reasonable?[/QUOTE]
Yes very. - I charge £200 just for the repair (plus parts), more if it requires a descale but these are London prices with London costs, it is soon going to cost me £12.50 on top of the £11.50 just to drive in, let alone the parking £4+ per hour (2 hours to travel 17 miles each way).

 

[townfanjon]

Cotherm stats , not my favourite.
Please get the wireing sorted to both stats before theres a fire

Townfanjon aka townfanjohn

 

[chris watkins]

Cotherm stats , not my favourite.
Please get the wireing sorted to both stats before theres a fire

Townfanjon aka townfanjohn

I will only fit TSR's with crimped con's

 

[townfanjon]

I will only fit TSR's with crimped con's

Yes good call that Chris .
Prefer the Thermtec stats .

 

[Welder]

AND making sure it suitable for a st/st cylinder so NO copper pockets in its construction and incaloy.