Ravenheat combi RSF84ET no hot water problem

[Marco]

Hi was called out to look at this for a letting agent and am still new to fault finding.

Checked the obvious things: Pressure just over 1bar, CH works fine. On winter setting with CH working, you turn on a hot tap you hear a slight click and burner goes off!so what could it be? I would have thought it could be the diverter diaphram if burner stayed on, but it doesnnt?

Managed to get the MIs online and they suggest the following:

Is the microswitch on shunt valve being operated mechanically?(how do I check this though?) Yes - check/replace 3way micro switch. if No (and flow is > 3ltrs/min which it is)replace shunt valve.

by shunt valve do they mean 3 way diverter valve?

So any tips/ideas what it could be? They want a price off me before I go ahead and with it being the bank holiday, not sure what parts prices are even if I knew which parts it is likely to be. or times to replace!

Any help would be good!!

 

[fixter1]

put it in summer mode and try dhw see if burner lights up ... test dhw switch with continuity, 2 green wires on control board

 

[aggis]

Hi.
The shunt valve is the 3 way valve.
The microswitch is ontop of the dhw diaphragm section, held with a large metal clip, thro the base of the plastic m/s box. Just slide it out using snipe nose pliers.
With m/s removed & electric's on, manually push the switch in,pump then fan run then boiler should fire [ might be a double switch]
If it fires you need a 3 way valve, with some manufactures you can change just the diaphragm.
If it doesn't you need to check the m/s with your multimeter.

 

[Marco]

put it in summer mode and try dhw see if burner lights up ... test dhw switch with continuity, 2 green wires on control board

Cheers fixter - in summer mode the burner did not light up. by DHW switch do you mean the main switch (goes from off/summer/winter) or dhw sensor?

 

[Marco]

Hi.
The shunt valve is the 3 way valve.
The microswitch is ontop of the dhw diaphragm section, held with a large metal clip, thro the base of the plastic m/s box. Just slide it out using snipe nose pliers.
With m/s removed & electric's on, manually push the switch in,pump then fan run then boiler should fire [ might be a double switch]
If it fires you need a 3 way valve, with some manufactures you can change just the diaphragm.
If it doesn't you need to check the m/s with your multimeter.

cheers Aggis - sounds like I wouldn't need to drain down to do these tests or change M/s if required? Only if need to swop the 3 way valve? What sort of readings should i be looking for on the M/s?

 

[Billy Bob Bob]

push the switch in i think its two wire on this set up if your getting continuity the boiler should fire for dhw with the switch depressed you could just put a Giannini diaprahm in or fit the complete valve the trouble is if the diaprahms shot sometimes the other parts of the valve might be worn as well get the diaprahm or valve here [DLMURL="http://www.abcotuk.co.uk/subcategory.aspx?catid=C2-19"]Printed Circuit Board | Circulating Pumps | Diaphragms | Thermostats | Fuses[/DLMURL] they are a lot cheaper and are oe parts i believe you will need a type f but it will be stamped on the valve

 

[Marco]

cheers gas man - yes looks like type F, will see how price compares to local suppliers in the morning and if they have Ravenheat parts in stock. Can't see the microswitch on there though, if that has failed. I've favourited the supplier for future reference!

 

[Billy Bob Bob]

cheers gas man - yes looks like type F, will see how price compares to local suppliers in the morning and if they have Ravenheat parts in stock. Can't see the microswitch on there though, if that has failed. I've favourited the supplier for future reference!

think they come with new micro switches from abkot ask them if you order from them your supplier will quote about £120 + probably dont forget to get replacement washers for it as well

 

[Marco]

top tip there thanks gas man. Price included Ms but washer were £1 extra! Placed order, as gave letting agent 2 price options: wait a day and save £40 or go for local instock price - surprise....they chose the cheapest even though tenent not had hot water since Fri! ordered some fuses and other washers for van stock as well. Damn spent my mark up on parts already!

 

[Billy Bob Bob]

when you know where to get spares at the right price we make the mark up not the suppliers,glad you are getting it sorted and making some money jobs a good un

 

[kennedy1978mark]

for diverter valves for ravenheat go on ezypart.co.uk .. used them loads of times and i have always found them to be really cheap .. last time i bought a diverter was for a rsf100 it was about £60-70 delivered next day !! worth a look(washers included)


just looked and there £61 next day delivery

 

[Marco]

Cheers bud sounds similar to Abcot, now having to wait for the delivery, which is the downside. Will save the ezypart.co.uk to favourites as its always good to have a few cheap suppliers!