Back up to combi boiler

[lordyjordy111]

Hi

I went to a landlords today and the guy who had installed the combi boiler (in loft) had hooked up Red ring power stream 10.8kw instant water heater as a back up to the combi boiler.
It was isolated and drained whilst the combi was working, and connected in a similar way you would by pass a water softener.
If the combi broke down the landlord would turn the combi off and open the valves to the heater and flip the switch.
The landlord has actually done this and loved it - no more angry tenant.

He said the shower didn't warm up at all and bath took about half hour to fill. But it meant the tenant could have a hot bath which gave him time......

Any one seen this before. Or any other good ideas for back up hot to a combi apart from an electric shower.
I find most customers don't want an electric shower as they are basically rubbish- which they are imo

Thanks in advance

 

[Aire]

Are you saying he uses the shower body as a water heater to feed all the taps if the combi packs in?

 

[Riley]

No it’s an instantaneous water heater

 

[lordyjordy111]

Basically yeah. It doesn't look like a normal instant shower. Looks a bit like a consumer unit with hot and cold connection...

 

[Aire]

No it’s an instantaneous water heater

Yeah just googled it, never seen one before but not a bad idea as a backup.

 

[lordyjordy111]

@Riley yes that's right but the principle is the same is it not? Mains Cold water in hot water out..... just never seen this before but seems a good idea I have to be honest. I sure there will be pitfalls though. Just wondered what you guys thought

 

[lordyjordy111]

What concerns me is the leggiona risk. I'm sure the health and safety brigade will have something to say. Your in big trouble if you do this and the tenant goes toes up. Lol

 

[Aire]

The shower wouldnt work as the heater will work similarly to an electric shower where it regulates the pressure down and the cold mains from the shower side will over power it.
30 mins running a bath will rape the electricity meter but it's better than having cold water.

 

[Aire]

What concerns me is the leggiona risk. I'm sure the health and safety brigade will have something to say. Your in big trouble if you do this and the tenant goes toes up. Lol

Can't see legionella been a risk as the water isn't stored

 

[lordyjordy111]

isn't

I know but what if the unit isn't drained after use. Left with water in it for an extended period then opened again. Obviously not 100% sure this is a problem but have my reservations.
There is definitely a huge market for something that can easily back up a combi.......

 

[Aire]

I know but what if the unit isn't drained after use. Left with water in it for an extended period then opened again. Obviously not 100% sure this is a problem but have my reservations.
There is definitely a huge market for something that can easily back up a combi...

Yeah I see your point, and if it's in a loft, the temp of the water could easily rise above 20°

 

[gmartine]

Sounds like the landlord paid for a back-up instead of just buying a decent combi in the first place?
Ok I'm being a little facetious but still, a heating emergency is far more critical than a HW one and yet the landlord still has to turn up and turn on the "back-up" water heater instead of the tenant just using an electric shower. Same sort of cost, same sort of install, doesn't make the same sort of sense to me.

 

[SJB060685]

Not gas qualified but Mistral do an oil boiler combi with an immersion heater backup in the event of a burner or oil problem. Never seen one personally but do know this is available on their top end combi’s

 

[Rob Foster]

Electricity from the grid is way more expensive than natural gas. However oil or liquified gas
is almost as expensive so the plus side of this arrangement can be seen. What kw is it ? what is its flow rate ? is it specified for continuous use and is the wiring up,to spec are the potential pit falls in my opinion. Intresting Rob Foster aka centralheatking