Good morning

I am refurbishing my guest bathroom (used only a few weeks per year).. For the moment there is a "shower heater" apparently with a "hand" shower and 2 taps in the lower part of the shower

I change the shower system to fix a rain shower mixer

The existing water (or shower) heater is not working any more (just moved in 2 months ago and never checked)

In Homepro I had a look at the "instant" systems to get hot water and prices go from 2000 till 7000 or more.. They gave me a type of explanation I could not understand saying I should go for the more expensive ones as I could not set a shower heater but a water heater.. The employee finally told me that if I use what they call shower heater, the guarantee would not work and it would break very soon as not adapted for my shower system..I don t understand what they try to explain and frankly speaking as it will be used only a few weeks per year (even maybe not as guests mainly come in summer time) I am not ready to go for expensive water heater unless really compulsory.

Could someone explain me what I should buy and why ?

Thank you very much in advance

Have a nice day

You need multi point unit to mix/turn off flow at taps.  Shower is normally single point and flow controlled prior to heating - after heating must have free water flow.

 

See no reason in most cases to have anything but shower hot water/hand unit here - tap for basin can just be cool as never that cold.  Especially for guest room.

Guest room ,only used few weeks a year , just get a shower water heater ,cold water

in hot water out shower head , that's all you need , a good one 4K Baht good enough

for what you want , check out Stiebel Eltron  German brand made in Thailand , get 

the one with copper heater inside  

regards Worgerdie

As above, if you want to feed a mixer you need a multi-point heater. 

 

The regular shower heaters are not intended to have their outlet blocked (it's used as a vent in the event of a thermostat failure) and whilst it may "work" it's less than safe and could make a large bang if it ever boils.

 

Hello

Would this be convenient ? again, it will just be on for a few minutes taking a short shower (we and our family are used no to waste water in unnecessary long showers) and turned off immediately after.. Thank you

Have a good day

https://www.lazada.co.th/products/qpio-4500-10-i4462294541-s17976222939.html?

Many reviews available from this sales point (seems to be generic with many sales names) - very cheap (as are a lot of electronics recently from China).  It appears to be single point so only for a shower.

https://www.lazada.co.th/products/konig-4500w-i4329977063-s17249035242.html

Thanks a lot to all.

After Crossy s info (outlet blocked) I understood the point

Have a good day

6 hours ago, worgeordie said:

Guest room ,only used few weeks a year , just get a shower water heater ,cold water

in hot water out shower head , that's all you need , a good one 4K Baht good enough

for what you want , check out Stiebel Eltron  German brand made in Thailand , get 

the one with copper heater inside  

regards Worgerdie

Thank you.. Finally went for multi point water heater (following Crossy s explanation) but followed your advice and went for a Stiebel Eltron

Have a good day